The penta-EF hand (PEF) family; The penta-EF hand (PEF) family contains a group of five EF-hand calcium-binding proteins, including several classical calpain large catalytic subunits (CAPN1, 2, 3, 8, 9, 11, 12, 13, 14), two calpain small subunits (CAPNS1 and CAPNS2), as well as non-calpain PEF proteins, ALG-2 (apoptosis-linked gene 2, also termed programmed cell death protein 6, PDCD6), peflin, sorcin, and grancalcin. Based on the sequence similarity of EF1 hand, ALG-2 and peflin have been classified into group I PEF proteins. Calcium-dependent protease calpain subfamily members, sorcin and grancalcin, are group II PEF proteins. Calpains (EC 3.4.22.17) are calcium-activated intracellular cysteine proteases that play important roles in the degradation or functional modulation in a variety of substrates. They have been implicated in a number of physiological processes such as cell cycle progression, remodeling of cytoskeletal-cell membrane attachments, signal transduction, gene expression and apoptosis. ALG-2 is a pro-apoptotic factor that forms a homodimer in the cell or a heterodimer with its closest paralog peflin through their EF5s. Peflin is a 30-kD PEF protein with a longer N-terminal hydrophobic domain than any other member of the PEF family, and it contains nine nonapeptide (A/PPGGPYGGP) repeats. It exists only as a heterodimer with ALG-2. The dissociation of heterodimer occurs in the presence of Ca2+. ALG-2 interacts with various proteins in a Ca2+-dependent manner. Sorcin (for soluble resistance-related calcium binding protein) is a soluble resistance-related calcium-binding protein that participates in the regulation of calcium homeostasis in cells. Grancalcin is a cytosolic Ca2+-binding protein specifically expressed in neutrophils and monocytes/macrophages. It plays a key role in leukocyte-specific functions that are responsible for host defense. Grancalcin can form a heterodimer together with sorcin. Members in this family contain five EF-hand motifs attached to an N-terminal region of variable length containing one or more short Gly/Pro-rich sequences. These proteins form homodimers or heterodimers through pairing between the 5th EF-hands from the two molecules. Unlike calmodulin, the PEF domains do not undergo major conformational changes upon binding Ca2+.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 79313177 168 NIVACFQAADRDNSGFIDDKELQGALSSYNQS-FSIRTVHLLMYLFTNSNVRKIGPKEFTSLFFSLQNWRSIFERFDKDR 246
Cdd:cd16180   1 ELRRIFQAVDRDRSGRISAKELQRALSNGDWTpFSIETVRLMINMFDRDRSGTINFDEFVGLWKYIQDWRRLFRRFDRDR 80

                        90       100       110       120
                ....*....|....*....|....*....|....*....|....*....
gi 79313177 247 SGRIDTNELRDALMSLGFSVSPVILDLLVSKFDKsgGRNRAIEYDNFIE 295
Cdd:cd16180  81 SGSIDFNELQNALSSFGYRLSPQFVQLLVRKFDR--RRRGSISFDDFVE 127

Penta-EF hand, calcium binding motifs, found in Group I PEF proteins; The family corresponds to Group I PEF proteins that have been found not only in higher animals but also in lower animals, plants, fungi and protists. Group I PEF proteins include apoptosis-linked gene 2 protein (ALG-2), peflin and similar proteins. ALG-2, also termed programmed cell death protein 6 (PDCD6), is a widely expressed calcium-binding modulator protein associated with cell proliferation and death, as well as cell survival. It forms a homodimer in the cell or a heterodimer with its closest paralog peflin. Among the PEF proteins, ALG-2 can bind three Ca2+ ions through its EF1, EF3, and EF5 hands, where it is unique in that its EF5 hand binds Ca2+ ion in a canonical coordination. Peflin is a ubiquitously expressed 30-kD PEF protein containing five EF-hand motifs in its C-terminal domain and a longer N-terminal hydrophobic domain (NHB domain) than any other member of the PEF family. The NHB domain harbors nine repeats of a nonapeptide (A/PPGGPYGGP). Peflin may modulate the function of ALG-2 in Ca2+ signaling. It exists only as a heterodimer with ALG-2, and binds two Ca2+ ions through its EF1 and EF3 hands. Its additional EF5 hand is unpaired and does not bind Ca2+ ion but mediates the heterodimerization with ALG-2. The dissociation of heterodimer occurs in the presence of Ca2+.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 79313177 168 NIVACFQAADRDNSGFIDDKELQGALSSYNQS-FSIRTVHLLMYLFTNSNVRKIGPKEFTSLFFSLQNWRSIFERFDKDR 246
Cdd:cd16180   1 ELRRIFQAVDRDRSGRISAKELQRALSNGDWTpFSIETVRLMINMFDRDRSGTINFDEFVGLWKYIQDWRRLFRRFDRDR 80

                        90       100       110       120
                ....*....|....*....|....*....|....*....|....*....
gi 79313177 247 SGRIDTNELRDALMSLGFSVSPVILDLLVSKFDKsgGRNRAIEYDNFIE 295
Cdd:cd16180  81 SGSIDFNELQNALSSFGYRLSPQFVQLLVRKFDR--RRRGSISFDDFVE 127

EF-hand domain pair;

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 79313177   236 RSIFERFDKDRSGRIDTNELRDALMSL--GFSVSPVILDLLVSKFDKSGgrNRAIEYDNFIEYV 297
Cdd:pfam13499   5 KEAFKLLDSDGDGYLDVEELKKLLRKLeeGEPLSDEEVEELFKEFDLDK--DGRISFEEFLELY 66

centrin; Provisional

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 79313177  236 RSIFERFDKDRSGRIDTNELRDALMSLGF-----SVSPVILDLlvskfDKSGgrNRAIEYDNFIE 295
Cdd:PTZ00183  20 REAFDLFDTDGSGTIDPKELKVAMRSLGFepkkeEIKQMIADV-----DKDG--SGKIDFEEFLD 77

Penta-EF hand, calcium binding motifs, found in Group I PEF proteins; The family corresponds to Group I PEF proteins that have been found not only in higher animals but also in lower animals, plants, fungi and protists. Group I PEF proteins include apoptosis-linked gene 2 protein (ALG-2), peflin and similar proteins. ALG-2, also termed programmed cell death protein 6 (PDCD6), is a widely expressed calcium-binding modulator protein associated with cell proliferation and death, as well as cell survival. It forms a homodimer in the cell or a heterodimer with its closest paralog peflin. Among the PEF proteins, ALG-2 can bind three Ca2+ ions through its EF1, EF3, and EF5 hands, where it is unique in that its EF5 hand binds Ca2+ ion in a canonical coordination. Peflin is a ubiquitously expressed 30-kD PEF protein containing five EF-hand motifs in its C-terminal domain and a longer N-terminal hydrophobic domain (NHB domain) than any other member of the PEF family. The NHB domain harbors nine repeats of a nonapeptide (A/PPGGPYGGP). Peflin may modulate the function of ALG-2 in Ca2+ signaling. It exists only as a heterodimer with ALG-2, and binds two Ca2+ ions through its EF1 and EF3 hands. Its additional EF5 hand is unpaired and does not bind Ca2+ ion but mediates the heterodimerization with ALG-2. The dissociation of heterodimer occurs in the presence of Ca2+.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 79313177 168 NIVACFQAADRDNSGFIDDKELQGALSSYNQS-FSIRTVHLLMYLFTNSNVRKIGPKEFTSLFFSLQNWRSIFERFDKDR 246
Cdd:cd16180   1 ELRRIFQAVDRDRSGRISAKELQRALSNGDWTpFSIETVRLMINMFDRDRSGTINFDEFVGLWKYIQDWRRLFRRFDRDR 80

                        90       100       110       120
                ....*....|....*....|....*....|....*....|....*....
gi 79313177 247 SGRIDTNELRDALMSLGFSVSPVILDLLVSKFDKsgGRNRAIEYDNFIE 295
Cdd:cd16180  81 SGSIDFNELQNALSSFGYRLSPQFVQLLVRKFDR--RRRGSISFDDFVE 127

EF-hand, calcium binding motif, found in apoptosis-linked gene 2 protein (ALG-2) and similar proteins; ALG-2, also termed programmed cell death protein 6 (PDCD6), or probable calcium-binding protein ALG-2, is one of the prototypic members of the penta EF-hand protein family. It is a widely expressed calcium-binding modulator protein associated with cell proliferation and death, as well as cell survival. ALG-2 acts as a pro-apoptotic factor participating in T cell receptor-, Fas-, and glucocorticoid-induced programmed cell death, and also serves as a useful molecular marker for the prognosis of cancers. Moreover, ALG-2 functions as a calcium ion sensor at endoplasmic reticulum (ER) exit sites, and modulates ER-stress-stimulated cell death and neuronal apoptosis during organ formation. Furthermore, ALG-2 can mediate the pro-apoptotic activity of cisplatin or tumor necrosis factor alpha (TNFalpha) through the down-regulation of nuclear factor-kappaB (NF-kappaB) expression. It also inhibits angiogenesis through PI3K/mTOR/p70S6K pathway by interacting of vascular endothelial growth factor receptor-2 (VEGFR-2). In addition, nuclear ALG-2 may participate in the post-transcriptional regulation of Inositol Trisphosphate Receptor Type 1 (IP3R1) pre-mRNA at least in part by interacting with CHERP (Ca2+ homeostasis endoplasmic reticulum protein) calcium-dependently. ALG-2 contains five serially repeated EF-hand motifs and interacts with various proteins, including ALG-2-interacting protein X (Alix), Fas, annexin XI, death-associated protein kinase 1 (DAPk1), Tumor susceptibility gene 101 (TSG101), Sec31A, phospholipid scramblase 3 (PLSCR3), the P-body component PATL1, and endosomal sorting complex required for transport (ESCRT)-III-related protein IST1, in a calcium-dependent manner. It forms a homodimer in the cell or a heterodimer with its closest paralog peflin. Among the PEF proteins, ALG-2 can bind three Ca2+ ions through its EF1, EF3, and EF5 hands, where it is unique in that its EF5 hand binds Ca2+ ion in a canonical coordination.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 79313177 173 FQAADRDNSGFIDDKELQGALSSYNQS-FSIRTVHLLMYLFTNSNVRKIGPKEFTSLFFSLQNWRSIFERFDKDRSGRID 251
Cdd:cd16183   6 FQRVDKDRSGQISATELQQALSNGTWTpFNPETVRLMIGMFDRDNSGTINFQEFAALWKYITDWQNCFRSFDRDNSGNID 85

                        90       100       110       120
                ....*....|....*....|....*....|....*....|....
gi 79313177 252 TNELRDALMSLGFSVSPVILDLLVSKFDKSGGRNraIEYDNFIE 295
Cdd:cd16183  86 KNELKQALTSFGYRLSDQFYDILVRKFDRQGRGT--IAFDDFIQ 127

The penta-EF hand (PEF) family; The penta-EF hand (PEF) family contains a group of five EF-hand calcium-binding proteins, including several classical calpain large catalytic subunits (CAPN1, 2, 3, 8, 9, 11, 12, 13, 14), two calpain small subunits (CAPNS1 and CAPNS2), as well as non-calpain PEF proteins, ALG-2 (apoptosis-linked gene 2, also termed programmed cell death protein 6, PDCD6), peflin, sorcin, and grancalcin. Based on the sequence similarity of EF1 hand, ALG-2 and peflin have been classified into group I PEF proteins. Calcium-dependent protease calpain subfamily members, sorcin and grancalcin, are group II PEF proteins. Calpains (EC 3.4.22.17) are calcium-activated intracellular cysteine proteases that play important roles in the degradation or functional modulation in a variety of substrates. They have been implicated in a number of physiological processes such as cell cycle progression, remodeling of cytoskeletal-cell membrane attachments, signal transduction, gene expression and apoptosis. ALG-2 is a pro-apoptotic factor that forms a homodimer in the cell or a heterodimer with its closest paralog peflin through their EF5s. Peflin is a 30-kD PEF protein with a longer N-terminal hydrophobic domain than any other member of the PEF family, and it contains nine nonapeptide (A/PPGGPYGGP) repeats. It exists only as a heterodimer with ALG-2. The dissociation of heterodimer occurs in the presence of Ca2+. ALG-2 interacts with various proteins in a Ca2+-dependent manner. Sorcin (for soluble resistance-related calcium binding protein) is a soluble resistance-related calcium-binding protein that participates in the regulation of calcium homeostasis in cells. Grancalcin is a cytosolic Ca2+-binding protein specifically expressed in neutrophils and monocytes/macrophages. It plays a key role in leukocyte-specific functions that are responsible for host defense. Grancalcin can form a heterodimer together with sorcin. Members in this family contain five EF-hand motifs attached to an N-terminal region of variable length containing one or more short Gly/Pro-rich sequences. These proteins form homodimers or heterodimers through pairing between the 5th EF-hands from the two molecules. Unlike calmodulin, the PEF domains do not undergo major conformational changes upon binding Ca2+.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 79313177 173 FQAADRDnSGFIDDKELQGALSS-----YNQSFSIRTVHLLMYLFTNSNVRKIGPKEFTSLFFSLQNWRSIFERFDKDRS 247
Cdd:cd15897   6 FQAVAGD-DGEISATELQQALSNvgwthFDLGFSLETCRSMIAMMDRDHSGKLNFSEFKGLWNYIKAWQEIFRTYDTDGS 84

                        90       100       110       120
                ....*....|....*....|....*....|....*....|....*...
gi 79313177 248 GRIDTNELRDALMSLGFSVSPVILDLLVSKFDKSGGRnraIEYDNFIE 295
Cdd:cd15897  85 GTIDSNELRQALSGAGYRLSEQTYDIIIRRYDRGRGN---IDFDDFIQ 129

Penta-EF hand, calcium binding motifs, found in sorcin, grancalcin, and similar proteins; The family corresponds to the second group of penta-EF hand (PEF) proteins that includes sorcin, grancalcin, and similar proteins. Sorcin, also termed 22 kDa Ca2+-binding protein, CP-22, or V19, is a soluble resistance-related calcium-binding protein that is expressed in normal mammalian tissues, such as the liver, lungs and heart. It contains a flexible glycine and proline-rich N-terminal extension and five EF-hand motifs that associate with membranes in a calcium-dependent manner. It may harbor three potential Ca2+ binding sites through its EF1, EF2 and EF3 hands. However, binding of only two Ca2+/monomer suffices to trigger the conformational change that exposes hydrophobic regions and leads to interaction with the respective targets. Sorcin forms homodimers through the association of the unpaired EF5 hand. Among the PEF proteins, sorcin is unique in that it contains potential phosphorylation sites by cAMP-dependent protein kinase (PKA), and it can form a tetramer at slightly acid pH values although remaining a stable dimer at neutral pH. Grancalcin (GCA) is a cytosolic Ca2+-binding protein specifically expressed in neutrophils and monocytes/macrophages. It can strongly interact with sorcin to form a heterodimer and further modulate the function of sorcin. GCA exists as homodimers in solution. It contains five EF-hand motifs attached to an N-terminal region of an approximately 50 residue-long segment rich in glycines and prolines. In contrast with sorcin, GCA binds two Ca2+ ions through its EF1 and EF3 hands.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 79313177 173 FQA-ADRDnsGFIDDKELQGALSS-----YNQSFSIRTVHLLMYLFTNSNVRKIGPKEFTSLFFSLQNWRSIFERFDKDR 246
Cdd:cd16181   6 FSAvAGQD--GQIDADELQRCLTQsgisgNYQPFSLETCRLMIAMLDRDHSGKMGFNEFKELWAALNQWKTTFMQYDRDR 83

                        90       100       110       120
                ....*....|....*....|....*....|....*....|....*...
gi 79313177 247 SGRIDTNELRDALMSLGFSVSPVILDLLVSKFdksgGRNRAIEYDNFI 294
Cdd:cd16181  84 SGTVEPQELQQAIRSFGYNLSPQALNVIVKRY----SKNGRITFDDFV 127

Penta-EF hand, calcium binding motifs, found in grancalcin; Grancalcin (GCA) is a cytosolic Ca2+-binding protein specifically expressed in neutrophils and monocytes/macrophages. It displays a Ca2+-dependent translocation to granules and plasma membrane upon neutrophil activation, suggesting roles in granule-membrane fusion and degranulation of neutrophils. It may also play a role in the regulation of vesicle/granule exocytosis through the reversible binding of secretory vesicles and plasma membranes upon the presence of calcium. Moreover, GCA is involved in inflammation, as well as in the process of adhesion of neutrophils to fibronectin. It plays a key role in leukocyte-specific functions that are responsible for host defense, and affects the function of integrin receptors on immune cells through binding to L-plastin in the absence of calcium. Furthermore, GCA can strongly interact with sorcin to form a heterodimer, and further modulate the function of sorcin. GCA exists as homodimers in solution. It contains five EF-hand motifs attached to an N-terminal region of an approximately 50 residue-long segment rich in glycines and prolines. GCA binds two Ca2+ ions through its EF1 and EF3 hands.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 79313177 182 GFIDDKELQGALSSYNQS-----FSIRTVHLLMYLFTNSNVRKIGPKEFTSLFFSLQNWRSIFERFDKDRSGRIDTNELR 256
Cdd:cd16186  14 GEVDAEELQRCLTQSGINgtytpFSLETCRIMIAMLDRDHTGKMGFNEFKELWAALNAWKQNFMTVDQDRSGTVEPHELR 93

                        90       100       110
                ....*....|....*....|....*....|....*...
gi 79313177 257 DALMSLGFSVSPVILDLLVSKFDKSGgrnrAIEYDNFI 294
Cdd:cd16186  94 QAIGAMGYRLSPQTLTTIVKRYSKNG----RIYFDDYV 127

Penta-EF hand, calcium binding motifs, found in m-type calpain (CAPN2); CAPN2, also termed millimolar-calpain (m-calpain), or calpain-2 catalytic subunit, or calcium-activated neutral proteinase 2 (CANP 2), or calpain large polypeptide L2, or calpain-2 large subunit, is a ubiquitously expressed 80-kDa Ca2+-dependent intracellular cysteine protease that contains a short N-terminal anchor helix, followed by a calpain cysteine protease (CysPc) domain, a C2-domain-like (C2L) domain, and a C-terminal Ca2+-binding penta-EF-hand (PEF) domain. The catalytic subunit CAPN2 in complex with a regulatory subunit encoded by CAPNS1 forms an m-calpain heterodimer. CAPN2 acts as the key protease responsible for N-methyl-d-aspartic acid (NMDA)-induced cytoplasmic polyadenylation element-binding protein 3 (CPEB3) degradation in neurons. It cleaves several components of the focal adhesion complex, such as FAK and talin, triggering disassembly of the complex at the rear of the cell. The stimulation of CAPN2 activity is required for Golgi antiapoptotic proteins (GAAPs) to promote cleavage of FA kinase (FAK), cell spreading, and enhanced migration. calpain 2 is also involved in the onset of glial differentiation. It regulates proliferation, survival, migration, and tumorigenesis of breast cancer cells through a PP2A-Akt-FoxO-p27(Kip1) signaling cascade. Its expression is associated with response to platinum based chemotherapy, progression-free and overall survival in ovarian cancer. Moreover, CAPN2 may play a role in fundamental mitotic functions, such as the maintenance of sister chromatid cohesion. The activation of CAPN2 plays an essential role in hippocampal synaptic plasticity and in learning and memory. In the eye, CAPN2, together with a lens-specific variant of CAPN3, is responsible for proteolytic cleavages of alpha and beta-crystallin. Overactivated alpha and beta-crystallin can lead to cataract formation. Sometimes, CAPN2 compensates for loss of CAPN1, and both calpain isoforms are involved in AngII-induced aortic aneurysm formation. The main phosphorylation sites in m-calpain are Ser50 and Ser369/Thr370.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 79313177 200 FSIRTVHLLMYLFTNSNVRKIGPKEFTSLFFSLQNWRSIFERFDKDRSGRIDTNELRDALMSLGFSVSPVILDLLVSKFd 279
Cdd:cd16199  40 FSIETCKIMVDMLDSDGSGKLGLKEFYILWTKIQKYQKIYREIDVDRSGTMNSYEMRKALEEAGFKLPCQLHQVIVARF- 118

                        90
                ....*....|....*
gi 79313177 280 ksGGRNRAIEYDNFI 294
Cdd:cd16199 119 --ADDDLIIDFDNFV 131

Penta-EF hand, calcium binding motifs, found in calpain-9 (CAPN9); CAPN9, also termed digestive tract-specific calpain, or new calpain 4 (nCL-4), or protein CG36, is a calpain large subunit predominantly expressed in gastrointestinal tract. It plays a physiological role in the suppression of tumorigenesis. It acts as an important biomolecule link for the regression of colorectal cancer via intracellular calcium homeostasis. CAPN9 may also play a critical role in lumen formation. Moreover, CAPN9, together with CAPN8, forms an active protease complex, G-calpain, in which both proteins are essential for stability and activity. The G-Calpain has been implicated in gastric mucosal defense. Furthermore, down-regulation of calpain 9 has been linked to hypertensive heart and kidney disease in salt-sensitive Dahl rats. CAPN9 contains a short N-terminal anchor helix, followed by a calpain cysteine protease (CysPc) domain, a C2-domain-like (C2L) domain, and a C-terminal Ca2+-binding penta-EF-hand (PEF) domain.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 79313177 174 QAADRDNSgfIDDKELQGALSSYNQS--------FSIRTVHLLMYLFTNSNVRKIGPKEFTSLFFSLQNWRSIFERFDKD 245
Cdd:cd16192   8 QISGEDLE--ISAEELQYVLNAVLARtkeikfkkLSLLSCKNIISLMDTSGNGKLGFSEFKVFWDKLKKWIGLFLKYDAD 85

                        90       100       110       120
                ....*....|....*....|....*....|....*....|....*....
gi 79313177 246 RSGRIDTNELRDALMSLGFSVSPVILDLLVSKFdksGGRNRAIEYDNFI 294
Cdd:cd16192  86 RSGTMSSYELRSALKAAGFQLNNQLLQLIVLRY---ADDYLQIDFDDFL 131

Penta-EF hand, calcium binding motifs, found in calcium-dependent protease small subunit CAPNS1 and CAPNS2; CAPNS1, also termed calpain small subunit 1 (CSS1), or calcium-activated neutral proteinase small subunit (CANP small subunit), or calcium-dependent protease small subunit (CDPS), or calpain regulatory subunit, is a common 28-kDa regulatory calpain subunit encoded by the calpain small 1 (Capns1, also known as Capn4) gene. It acts as a binding partner to form a heterodimer with the 80 kDa calpain large catalytic subunit and is required in maintaining the activity of calpain. CAPNS1 plays a significant role in tumor progression of human cancer, and functions as a potential therapeutic target in human hepatocellular carcinoma (HCC), nasopharyngeal carcinoma (NPC), glioma, and clear cell renal cell carcinoma (ccRCC). It may be involved in regulating migration and cell survival through binding to the SH3 domain of Ras GTPase-activating protein (RasGAP). It may also modulate Akt/FoxO3A signaling and apoptosis through PP2A. CAPNS1 contains an N-terminal glycine rich domain and a C-terminal PEF-hand domain. CAPNS2, also termed calpain small subunit 2 (CSS2), is a novel tissue-specific 30 kDa calpain small subunit that lacks two oligo-Gly stretches characteristic of the N-terminal Gly-rich domain of CAPNS1. CAPNS2 acts as a chaperone for the calpain large subunit, and appears to be the functional equivalent of CAPNS1. However, CAPNS2 binds the large subunit much more weakly than CAPNS1 and it does not undergo the autolytic conversion typical of CAPNS1.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 79313177 200 FSIRTVHLLMYLFTNSNVRKIGPKEFTSLFFSLQNWRSIFERFDKDRSGRIDTNELRDALMSLGFSVSPVILDLLVSKFD 279
Cdd:cd16188  40 FGIDTCRSMVAVMDSDTTGKLGFEEFKYLWNNIKKWQGIYKQFDTDRSGTIGSQELPGAFEAAGFHLNEQLYQMIIRRYS 119

                        90
                ....*....|....*
gi 79313177 280 KSGGRnraIEYDNFI 294
Cdd:cd16188 120 DEDGN---MDFDNFI 131

Penta-EF hand, calcium binding motifs, found in mu-type calpain (CAPN1); CAPN1, also termed calpain-1 80-kDa catalytic subunit, or calpain-1 large subunit, or micromolar-calpain (muCANP), or calcium-activated neutral proteinase 1 (CANP 1), or cell proliferation-inducing gene 30 protein, is a ubiquitously expressed 80-kDa Ca2+-dependent intracellular cysteine protease that contains a short N-terminal anchor helix, followed by a calpain cysteine protease (CysPc) domain, a C2-domain-like (C2L) domain, and a C-terminal Ca2+-binding penta-EF-hand (PEF) domain. The catalytic subunit CAPN1 in complex with a regulatory subunit encoded by CAPNS1 forms a mu-calpain heterodimer. CAPN1 plays a central role in postmortem proteolysis and meat tenderization processes, as well as in regulation of proliferation and survival of skeletal satellite cells. It also acts as a novel regulator in IgE-mediated mast cell activation and could serve as a potential therapeutic target for the management of allergic inflammation. Moreover, CAPN1 is involved in neutrophil motility and functions as a potential target for intervention in inflammatory disease. It also facilitates age-associated aortic wall calcification and fibrosis through the regulation of matrix metalloproteinase 2 activity in vascular smooth muscle cells, and thus plays a role in hypertension and atherosclerosis. The proteolytic cleavage of beta-amyloid precursor protein and tau protein by CAPN1 may be involved in plaque formation. Furthermore, CAPN1 is activated in the brains of individuals with Alzheimer's disease. It is involved in the maintenance of a proliferative neural stem cell pool. The activation and macrophage inflammation of CAPN1 in hypercholesterolemic nephropathy is promoted by nicotinic acetylcholine receptor alpha1 (nAChRalpha1). In addition, CAPN1 displays a functional role in hemostasis, as well as in sickle cell disease.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 79313177 200 FSIRTVHLLMYLFTNSNVRKIGPKEFTSLFFSLQNWRSIFERFDKDRSGRIDTNELRDALMSLGFSVSPVILDLLVSKFD 279
Cdd:cd16198  40 FSLESCRSMVNLMDKDGNGKLGLVEFNILWNKIRNYLTIFRKFDLDKSGSMSAYEMRLALESAGFKLNNRLHQVIVARYA 119

                        90
                ....*....|....*
gi 79313177 280 KSggrNRAIEYDNFI 294
Cdd:cd16198 120 DP---NLAIDFDNFV 131

EF-hand, calcium binding motif, found in homologs of mammalian apoptosis-linked gene 2 protein (ALG-2); The family includes some homologs of mammalian apoptosis-linked gene 2 protein (ALG-2) mainly found in lower eukaryotes, such as a parasitic protist Leishmarua major and a cellular slime mold Dictyostelium discoideum. These homologs contains five EF-hand motifs. Due to the presence of unfavorable residues at the Ca2+-coordinating positions, their non-canonical EF4 and EF5 hands may not bind Ca2+. Two Dictyostelium PEF proteins are the prototypes of this family. They may bind to cytoskeletal proteins and/or signal-transducing proteins localized to detergent-resistant membranes named lipid rafts, and occur as monomers or weak homo- or heterodimers like ALG-2. They can serve as a mediator for Ca2+ signaling-related Dictyostehum programmed cell death (PCD).

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 79313177 168 NIVACFQAADRDNSGFIDDKELQGALSS--YNQSFSirTVHLLMYLFTNSNVRKIGPKEFTSLFFSLQNWRSIFERFDKD 245
Cdd:cd16185  67 NMQNGFEQRDTSRSGRLDANEVHEALAAsgFQLDPP--AFQALFRKFDPDRGGSLGFDDYIELCIFLASARNLFQAFDRQ 144

                ....*...
gi 79313177 246 RSGRIDTN 253
Cdd:cd16185 145 RTGRVTLD 152

EF-hand, calcium binding motif; A diverse superfamily of calcium sensors and calcium signal modulators; most examples in this alignment model have 2 active canonical EF hands. Ca2+ binding induces a conformational change in the EF-hand motif, leading to the activation or inactivation of target proteins. EF-hands tend to occur in pairs or higher copy numbers.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 79313177 236 RSIFERFDKDRSGRIDTNELRDALMSLGFSVSPVILDLLVSKFDKSG-GRnraIEYDNFIEYVH 298
Cdd:cd00051   3 REAFRLFDKDGDGTISADELKAALKSLGEGLSEEEIDEMIREVDKDGdGK---IDFEEFLELMA 63

Penta-EF hand, calcium binding motifs, found in calpain-13 (CAPN13), calpain-14 (CAPN14), and similar proteins; CAPN13, also termed calcium-activated neutral proteinase 13 (CANP 13), a 63.6 kDa calpain large subunit that exhibits a restricted tissue distribution with low levels of expression detected only in human testis and lung. In calpain family, CAPN13 is most closely related to calpain-14 (CAPN14). CAPN14, also termed calcium-activated neutral proteinase 14 (CANP 14), is a 76.7 kDa calpain large subunit that is most highly expressed in the oesophagus. Its expression and calpain activity can be induced by IL-13. Both CAPN13 and CAPN14 contain a calpain cysteine protease (CysPc) domain, a C2-domain-like (C2L) domain, and a C-terminal Ca2+-binding penta-EF-hand (PEF) domain.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 79313177 179 DNSGFIDDKELQGAL--------SSYNQSFSIRTVH-LLMYLFTNSNvRKIGPKEFTSLFFSLQNWRSIFERFDKDRSGR 249
Cdd:cd16195  11 DQGGELDAEQLQKLLnenllkglAGSGGGFSLDACRsMVALMDLSVN-GRLSLEEFSRLWKKLRKYKDIFQKADVSKSGF 89

                        90       100       110       120
                ....*....|....*....|....*....|....*....|....*
gi 79313177 250 IDTNELRDALMSLGFSVSPVILDLLVSKFDKSGGRnraIEYDNFI 294
Cdd:cd16195  90 LSLSELRNAIQAAGIRVSDDLLNLMALRYGDSSGR---ISFESFI 131

EF-hand motif found in eukaryotic phosphoinositide-specific phospholipase C (PI-PLC, EC 3.1.4.11) isozymes; PI-PLC isozymes are signaling enzymes that hydrolyze the membrane phospholipids phosphatidylinositol-4,5-bisphosphate (PIP2) to generate two important second messengers in eukaryotic signal transduction cascades, Inositol 1,4,5-trisphosphate (InsP3) and diacylglycerol (DAG). InsP3 triggers inflow of calcium from intracellular stores, while DAG, together with calcium, activates protein kinase C, which goes on to phosphorylate other molecules, leading to altered cellular activity. Calcium is required for the catalysis. This family corresponds to the four EF-hand motifs containing PI-PLC isozymes, including PI-PLC-beta (1-4), -gamma (1-2), -delta (1,3,4), -epsilon (1), -zeta (1), eta (1-2). Lower eukaryotes such as yeast and slime molds contain only delta-type isozymes. In contrast, other types of isoforms present in higher eukaryotes. This family also includes 1-phosphatidylinositol 4,5-bisphosphate phosphodiesterase 1 (PLC1) from fungi. Some homologs from plants contain only two atypical EF-hand motifs and they are not included. All PI-PLC isozymes except sperm-specific PI-PLC-zeta share a core set of domains, including an N-terminal pleckstrin homology (PH) domain, four atypical EF-hand motifs, a PLC catalytic core, and a single C2 domain. PI-PLC-zeta lacks the PH domain. The PLC catalytic core domain is a TIM barrel with two highly conserved regions (X and Y) split by a highly degenerate linker sequence. Most of EF-hand motifs found in PI-PLCs consist of a helix-loop-helix structure, but lack residues critical to metal binding. Moreover, the EF-hand region of most of PI-PLCs may have an important regulatory function, but it has yet to be identified. However, PI-PLC-zeta is a key exception. It is responsible for Ca2+ oscillations in fertilized oocytes and exhibits a high sensitivity to Ca2+ mediated through its EF-hand domain. In addition, PI-PLC-eta2 shows a canonical EF-loop directing Ca2+-sensitivity and thus can amplify transient Ca2+ signals. Also it appears that PI-PLC-delta1 can regulate the binding of PH domain to PIP2 in a Ca2+-dependent manner through its functionally important EF-hand domains. PI-PLCs can be activated by a variety of extracellular ligands, such as growth factors, hormones, cytokines and lipids. Their activation has been implicated in tumorigenesis and/or metastasis linked to migration, proliferation, growth, inflammation, angiogenesis and actin cytoskeleton reorganization. PI-PLC-beta isozymes are activated by G-protein coupled receptor (GPCR) through different mechanisms. However, PI-PLC-gamma isozymes are activated by receptor tyrosine kinase (RTK), such as Rho and Ras GTPases. In contrast, PI-PLC-epsilon are activated by both GPCR and RTK. PI-PLC-delta1 and PLC-eta 1 are activated by GPCR-mediated calcium mobilization. The activation mechanism for PI-PLC-zeta remains unclear.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 79313177 172 CFQAADRDNSGFIDDKELQGALSSYNQSFSIRTVHLLMYLFTNSNVRKIGPKEFTSLFFSLQN---WRSIFERFDKDRSG 248
Cdd:cd15898   5 QWIKADKDGDGKLSLKEIKKLLKRLNIRVSEKELKKLFKEVDTNGDGTLTFDEFEELYKSLTErpeLEPIFKKYAGTNRD 84

                        90       100       110       120
                ....*....|....*....|....*....|....*....|....*....
gi 79313177 249 RIDTNELRDALMSLGF-SVSPVILDLLVSKFDKsGGRNRAIEYDNFIEY 296
Cdd:cd15898  85 YMTLEEFIRFLREEQGeNVSEEECEELIEKYEP-ERENRQLSFEGFTNF 132

EF-hand domain;

                          10        20        30
                  ....*....|....*....|....*....|
gi 79313177   234 NWRSIFERFDKDRSGRIDTNELRDALMSLG 263
Cdd:pfam13405   1 ELREAFKLFDKDGDGKISLEELRKALRSLG 30

EF-hand, calcium binding motif; A diverse superfamily of calcium sensors and calcium signal modulators; most examples in this alignment model have 2 active canonical EF hands. Ca2+ binding induces a conformational change in the EF-hand motif, leading to the activation or inactivation of target proteins. EF-hands tend to occur in pairs or higher copy numbers.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 79313177 177 DRDNSGFIDDKELQGALssynqsfsirtvhllmylftnsnvRKIGPKeftslfFSLQNWRSIFERFDKDRSGRIDTNELR 256
Cdd:cd00051  10 DKDGDGTISADELKAAL------------------------KSLGEG------LSEEEIDEMIREVDKDGDGKIDFEEFL 59

                ....
gi 79313177 257 DALM 260
Cdd:cd00051  60 ELMA 63

EF-hand, calcium binding motif, found in the hexa-EF hand proteins family; The hexa-EF hand proteins family, also named the calbindin sub-family, contains a group of six EF-hand Ca2+-binding proteins, including calretinin (CR, also termed 29 kDa calbindin), calbindin D28K (CB, also termed vitamin D-dependent calcium-binding protein, avian-type), and secretagogin (SCGN). CR is a cytosolic hexa-EF-hand calcium-binding protein predominantly expressed in a variety of normal and tumorigenic t-specific neurons of the central and peripheral nervous system. It is a multifunctional protein implicated in many biological processes, including cell proliferation, differentiation, and cell death. CB is highly expressed in brain tissue. It is a strong calcium-binding and buffering protein responsible for preventing a neuronal death as well as maintaining and controlling calcium homeostasis. SCGN is a six EF-hand calcium-binding protein expressed in neuroendocrine, pancreatic endocrine and retinal cells. It plays a crucial role in cell apoptosis, receptor signaling and differentiation. It is also involved in vesicle secretion through binding to various proteins, including interacts with SNAP25, SNAP23, DOC2alpha, ARFGAP2, rootletin, KIF5B, beta-tubulin, DDAH-2, ATP-synthase and myeloid leukemia factor 2. SCGN functions as a Ca2+ sensor/coincidence detector modulating vesicular exocytosis of neurotransmitters, neuropeptides or hormones. Although the family members share a significant amount of secondary sequence homology, they display altered structural and biochemical characteristics, and operate in distinct fashions. CB contains six EF-hand motifs in a single globular domain, where EF-hands 1, 3, 4, 5 bind four calcium ions. CR contains six EF-hand motifs within two independent domains, CR I-II and CR III-VI. They harbor two and four EF-hand motifs, respectively. The first 5 EF-hand motifs are capable of binding calcium ions, while the EF-hand 6 is inactive. SCGN consists of the three globular domains each of which contains a pair of EF-hand motifs. Human SCGN simultaneously binds four calcium ions through its EF-hands 3, 4, 5 and 6 in one high affinity and three low affinity calcium-binding sites. In contrast, SCGNs in other lower eukaryotes, such as D. rerio, X. laevis, M. domestica, G. gallus, O. anatinus, are fully competent in terms of six calcium-binding.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 79313177 173 FQAADRDNSGFIDDKEL-----------QGALSSYNQSFSIRTVHLLMYLFTNSNV------RKIGPKE--FTSLFFSLQ 233
Cdd:cd15902   5 WMHFDADGNGYIEGKELdsflrellkalNGKDKTDDEVAEKKKEFMEKYDENEDGKieirelANILPTEenFLLLFRREQ 84

                        90       100       110       120       130       140       150
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 79313177 234 NWRS------IFERFDKDRSGRIDTNELR----DALMSLGFSVSPVILD----LLVSKFDKSG-GRnraIEYDNF 293
Cdd:cd15902  85 PLISsvefmkIWRKYDTDGSGFIEAKELKgflkDLLLKNKKHVSPPKLDeytkLILKEFDANKdGK---LELDEM 156

DNA polymerase III subunits gamma and tau; Validated

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 79313177   31 PPPYGSSGSNPPPPYGSSASSPYAVPygAQPAPYGAPPSAPYASLPGDhnkPHKEKPHGASYGSPSPGGYGAHPSSGPSD 110
Cdd:PRK07764 590 PAPGAAGGEGPPAPASSGPPEEAARP--AAPAAPAAPAAPAPAGAAAA---PAEASAAPAPGVAAPEHHPKHVAVPDASD 664

                         90       100       110       120       130
                 ....*....|....*....|....*....|....*....|....*....|....*..
gi 79313177  111 YGGYGGAPQQSGHGGGYGGAPQQSGHGGGYGAPPPQASYGSPFASLVPSAFPPGTDP 167
Cdd:PRK07764 665 GGDGWPAKAGGAAPAAPPPAPAPAAPAAPAGAAPAQPAPAPAATPPAGQADDPAAQP 721

EF-hand, calcium binding motif, found in homologs of mammalian apoptosis-linked gene 2 protein (ALG-2); The family includes some homologs of mammalian apoptosis-linked gene 2 protein (ALG-2) mainly found in lower eukaryotes, such as a parasitic protist Leishmarua major and a cellular slime mold Dictyostelium discoideum. These homologs contains five EF-hand motifs. Due to the presence of unfavorable residues at the Ca2+-coordinating positions, their non-canonical EF4 and EF5 hands may not bind Ca2+. Two Dictyostelium PEF proteins are the prototypes of this family. They may bind to cytoskeletal proteins and/or signal-transducing proteins localized to detergent-resistant membranes named lipid rafts, and occur as monomers or weak homo- or heterodimers like ALG-2. They can serve as a mediator for Ca2+ signaling-related Dictyostehum programmed cell death (PCD).

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 79313177 232 LQNWrsiFERFDKDRSGRIDTNELRDALMS--LGFSVSPVilDLLVSKFDKSGgrNRAIeydNFIEYVH 298
Cdd:cd16185   2 LRQW---FRAVDRDRSGSIDVNELQKALAGggLLFSLATA--EKLIRMFDRDG--NGTI---DFEEFAA 60

EF-hand domain pair;

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 79313177   172 CFQAADRDNSGFIDDKELQGALSSYNQSFSIRTVHLlmylftnsnvrkigpkeftslffslqnwRSIFERFDKDRSGRID 251
Cdd:pfam13499   7 AFKLLDSDGDGYLDVEELKKLLRKLEEGEPLSDEEV----------------------------EELFKEFDLDKDGRIS 58

                  ....*....
gi 79313177   252 TNELRDALM 260
Cdd:pfam13499  59 FEEFLELYS 67

EF-hand, calcium binding motif; EF-hands are calcium-binding motifs that occur at least in pairs. Links between disease states and genes encoding EF-hands, particularly the S100 subclass, are emerging. Each motif consists of a 12 residue loop flanked on either side by a 12 residue alpha-helix. EF-hands undergo a conformational change unpon binding calcium ions.

                           10        20
                   ....*....|....*....|....*...
gi 79313177    235 WRSIFERFDKDRSGRIDTNELRDALMSL 262
Cdd:smart00054   2 LKEAFRLFDKDGDGKIDFEEFKDLLKAL 29

EF-hand, calcium binding motif, found in apoptosis-linked gene 2 protein (ALG-2) and similar proteins; ALG-2, also termed programmed cell death protein 6 (PDCD6), or probable calcium-binding protein ALG-2, is one of the prototypic members of the penta EF-hand protein family. It is a widely expressed calcium-binding modulator protein associated with cell proliferation and death, as well as cell survival. ALG-2 acts as a pro-apoptotic factor participating in T cell receptor-, Fas-, and glucocorticoid-induced programmed cell death, and also serves as a useful molecular marker for the prognosis of cancers. Moreover, ALG-2 functions as a calcium ion sensor at endoplasmic reticulum (ER) exit sites, and modulates ER-stress-stimulated cell death and neuronal apoptosis during organ formation. Furthermore, ALG-2 can mediate the pro-apoptotic activity of cisplatin or tumor necrosis factor alpha (TNFalpha) through the down-regulation of nuclear factor-kappaB (NF-kappaB) expression. It also inhibits angiogenesis through PI3K/mTOR/p70S6K pathway by interacting of vascular endothelial growth factor receptor-2 (VEGFR-2). In addition, nuclear ALG-2 may participate in the post-transcriptional regulation of Inositol Trisphosphate Receptor Type 1 (IP3R1) pre-mRNA at least in part by interacting with CHERP (Ca2+ homeostasis endoplasmic reticulum protein) calcium-dependently. ALG-2 contains five serially repeated EF-hand motifs and interacts with various proteins, including ALG-2-interacting protein X (Alix), Fas, annexin XI, death-associated protein kinase 1 (DAPk1), Tumor susceptibility gene 101 (TSG101), Sec31A, phospholipid scramblase 3 (PLSCR3), the P-body component PATL1, and endosomal sorting complex required for transport (ESCRT)-III-related protein IST1, in a calcium-dependent manner. It forms a homodimer in the cell or a heterodimer with its closest paralog peflin. Among the PEF proteins, ALG-2 can bind three Ca2+ ions through its EF1, EF3, and EF5 hands, where it is unique in that its EF5 hand binds Ca2+ ion in a canonical coordination.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 79313177 237 SIFERFDKDRSGRIDTNELRDALMSLGFS-VSPVILDLLVSKFDK--SGGRN 285
Cdd:cd16183   4 NVFQRVDKDRSGQISATELQQALSNGTWTpFNPETVRLMIGMFDRdnSGTIN 55

EF-hand, calcium binding motif, found in peflin and similar proteins; Peflin, also termed penta-EF hand (PEF) protein with a long N-terminal hydrophobic domain, or penta-EF hand domain-containing protein 1, is a ubiquitously expressed 30-kD PEF protein containing five EF-hand motifs in its C-terminal domain and a longer N-terminal hydrophobic domain (NHB domain) than any other member of the PEF family. The NHB domain harbors nine repeats of a nonapeptide (A/PPGGPYGGP). Peflin may modulate the function of ALG-2 in Ca2+ signaling. It exists only as a heterodimer with ALG-2, and binds two Ca2+ ions through its EF1 and EF3 hands. Its additional EF5 hand is unpaired and does not bind Ca2+ ion but mediates the heterodimerization with ALG-2. The dissociation of heterodimer occurs in the presence of Ca2+. In lower vertebrates, peflin may interact with transient receptor potential N (TRPN1), suggesting a potential role of peflin in fast transducer channel adaptation.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 79313177 173 FQAADRDNSGFIDDKELQGALSSYNQSFSIRTVHLLMYLFTNSNVRKIGPKEFTSLFFSLQNWRSIFERFDKDRSGRIDT 252
Cdd:cd16184  73 FQQFDRDRSGSIDENELHQALSQMGYRLSPQFVQFLVSKYDPRARRSLTLDQFIQVCVQLQSLTDAFRQRDTQMTGTITI 152

                .
gi 79313177 253 N 253
Cdd:cd16184 153 S 153

EF-hand motif found in eukaryotic phosphoinositide-specific phospholipase C (PI-PLC, EC 3.1.4.11) isozymes; PI-PLC isozymes are signaling enzymes that hydrolyze the membrane phospholipids phosphatidylinositol-4,5-bisphosphate (PIP2) to generate two important second messengers in eukaryotic signal transduction cascades, Inositol 1,4,5-trisphosphate (InsP3) and diacylglycerol (DAG). InsP3 triggers inflow of calcium from intracellular stores, while DAG, together with calcium, activates protein kinase C, which goes on to phosphorylate other molecules, leading to altered cellular activity. Calcium is required for the catalysis. This family corresponds to the four EF-hand motifs containing PI-PLC isozymes, including PI-PLC-beta (1-4), -gamma (1-2), -delta (1,3,4), -epsilon (1), -zeta (1), eta (1-2). Lower eukaryotes such as yeast and slime molds contain only delta-type isozymes. In contrast, other types of isoforms present in higher eukaryotes. This family also includes 1-phosphatidylinositol 4,5-bisphosphate phosphodiesterase 1 (PLC1) from fungi. Some homologs from plants contain only two atypical EF-hand motifs and they are not included. All PI-PLC isozymes except sperm-specific PI-PLC-zeta share a core set of domains, including an N-terminal pleckstrin homology (PH) domain, four atypical EF-hand motifs, a PLC catalytic core, and a single C2 domain. PI-PLC-zeta lacks the PH domain. The PLC catalytic core domain is a TIM barrel with two highly conserved regions (X and Y) split by a highly degenerate linker sequence. Most of EF-hand motifs found in PI-PLCs consist of a helix-loop-helix structure, but lack residues critical to metal binding. Moreover, the EF-hand region of most of PI-PLCs may have an important regulatory function, but it has yet to be identified. However, PI-PLC-zeta is a key exception. It is responsible for Ca2+ oscillations in fertilized oocytes and exhibits a high sensitivity to Ca2+ mediated through its EF-hand domain. In addition, PI-PLC-eta2 shows a canonical EF-loop directing Ca2+-sensitivity and thus can amplify transient Ca2+ signals. Also it appears that PI-PLC-delta1 can regulate the binding of PH domain to PIP2 in a Ca2+-dependent manner through its functionally important EF-hand domains. PI-PLCs can be activated by a variety of extracellular ligands, such as growth factors, hormones, cytokines and lipids. Their activation has been implicated in tumorigenesis and/or metastasis linked to migration, proliferation, growth, inflammation, angiogenesis and actin cytoskeleton reorganization. PI-PLC-beta isozymes are activated by G-protein coupled receptor (GPCR) through different mechanisms. However, PI-PLC-gamma isozymes are activated by receptor tyrosine kinase (RTK), such as Rho and Ras GTPases. In contrast, PI-PLC-epsilon are activated by both GPCR and RTK. PI-PLC-delta1 and PLC-eta 1 are activated by GPCR-mediated calcium mobilization. The activation mechanism for PI-PLC-zeta remains unclear.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|
gi 79313177 236 RSIFERFDKDRSGRIDTNELRDALMSLGFSVSPVILDLLVSKFDKSGgrNRAIEYDNFIE 295
Cdd:cd15898   3 RRQWIKADKDGDGKLSLKEIKKLLKRLNIRVSEKELKKLFKEVDTNG--DGTLTFDEFEE 60

chromosomal replication initiator protein DnaA;

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 79313177   31 PPPYGSSGSNPPPPYGSSASSPYAVPYGAQPAPYGAPpSAPYASLPGDHNKPHKEKPHGASYGSPSPggygaHPSSGPSD 110
Cdd:PRK14086 166 GWQQQRLGFPPRAPYASPASYAPEQERDREPYDAGRP-EYDQRRRDYDHPRPDWDRPRRDRTDRPEP-----PPGAGHVH 239

                         90       100       110       120
                 ....*....|....*....|....*....|....*....|....*...
gi 79313177  111 YGgyGGAPQQSGHGGGYGGAPQQSGHGGGYGAPPPQAsyGSPFASLVP 158
Cdd:PRK14086 240 RG--GPGPPERDDAPVVPIRPSAPGPLAAQPAPAPGP--GEPTARLNP 283

EF hand;

                          10        20
                  ....*....|....*....|..
gi 79313177   169 IVACFQAADRDNSGFIDDKELQ 190
Cdd:pfam13202   1 LKDTFRQIDLNGDGKISKEELR 22

DNA polymerase III subunits gamma and tau; Provisional

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 79313177   31 PPPYGSSGSNPPPPYGSSASS--PYAVPYGAQ-PAPYGAPPSAPYASLPgdhNKPHKEKPHGASYGSPspggyGAHPSSG 107
Cdd:PRK14954 395 PEPDLPQPDRHPGPAKPEAPGarPAELPSPASaPTPEQQPPVARSAPLP---PSPQASAPRNVASGKP-----GVDLGSW 466

                         90       100       110
                 ....*....|....*....|....*....|..
gi 79313177  108 PSDYGGYGGAPQQSGHGGGYGGAPQQSGHGGG 139
Cdd:PRK14954 467 QGKFMNFTRNGSRKQPVQASSSDAAQTGVFEG 498

EF-hand motif found in phosphoinositide phospholipase C delta (PI-PLC-delta); PI-PLC-delta isozymes represent a class of metazoan PI-PLCs that are some of the most sensitive to calcium among all PLCs. Their activation is modulated by intracellular calcium ion concentration, phospholipids, polyamines, and other proteins, such as RhoAGAP. Like other PI-PLC isozymes, PI-PLC-delta isozymes contain a core set of domains, including an N-terminal pleckstrin homology (PH) domain, four atypical EF-hand motifs, a PLC catalytic core, and a single C-terminal C2 domain. The PLC catalytic core domain is a TIM barrel with two highly conserved regions (X and Y) split by a highly degenerate linker sequence. There are three PI-PLC-delta isozymes (1, 3 and 4). PI-PLC-delta1 is relatively well characterized. It is activated by high calcium levels generated by other PI-PLC family members, and therefore functions as a calcium amplifier within the cell. Different PI-PLC-delta isozymes have different tissue distribution and different subcellular locations. PI-PLC-delta1 is mostly a cytoplasmic protein, PI-PLC-delta3 is located in the membrane, and PI-PLC-delta4 is predominantly detected in the cell nucleus. PI-PLC-delta isozymes is evolutionarily conserved even in non-mammalian species, such as yeast, slime molds and plants.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 79313177 169 IVACFQAADRDNSGFIDDKELQGALSSYNQSFSIRTVHLLMYLFTNSNVRKIGPKEFTsLFFSLQNWRS----IFERFDK 244
Cdd:cd16202   2 LKDQFRKADKNGDGKLSFKECKKLLKKLNVKVDKDYAKKLFQEADTSGEDVLDEEEFV-QFYNRLTKRPeieeLFKKYSG 80