Ca2+-binding protein, EF-hand superfamily [Signal transduction mechanisms];

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 294948080   7 EEQIAEFKEAFSLFDKDGDGTITTKELGTVMRslgqnpteAELQDMINEVDADGNGTIDFPEFLSLMARKMKDTDtEEEL 86
Cdd:COG5126    1 DLQRRKLDRRFDLLDADGDGVLERDDFEALFR--------RLWATLFSEADTDGDGRISREEFVAGMESLFEATV-EPFA 71

                         90       100       110       120       130       140
                 ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 294948080  87 IEAFKVFDRDGNGFISAAELRHVMTNLGekLTDEEVDEMIREADVDGDGQINYEEFVRMMM 147
Cdd:COG5126   72 RAAFDLLDTDGDGKISADEFRRLLTALG--VSEEEADELFARLDTDGDGKISFEEFVAAVR 130

EF-hand domain pair;

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 294948080   83 EEELIEAFKVFDRDGNGFISAAELRHVMTNL--GEKLTDEEVDEMIREADVDGDGQINYEEFVRMMM 147
Cdd:pfam13499   1 EEKLKEAFKLLDSDGDGYLDVEELKKLLRKLeeGEPLSDEEVEELFKEFDLDKDGRISFEEFLELYS 67

XopAW family type III secretion system calcium-binding effector;

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 294948080  39 SLGQNPTEAELQ-DMINEVDADGNGTIDFPEFLSLMARKmKDTDTEEELIEAFKVFDRDGNGFISAAELRHVMTN----L 113
Cdd:NF041410  18 SSTSSARSQQFQkQLFAKLDSDGDGSVSQDELSSALSSK-SDDGSLIDLSELFSDLDSDGDGSLSSDELAAAAPPppppP 96

                         90       100
                 ....*....|....*....|....*....
gi 294948080 114 GEKLTDEEVDEMIREADVDGDGQINYEEF 142
Cdd:NF041410  97 DQAPSTELADDLLSALDTDGDGSISSDEL 125

XopAW family type III secretion system calcium-binding effector;

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*..
gi 294948080  90 FKVFDRDGNGFISAAELRHVMTNLGEKLTDEEVDEMIREADVDGDGQINYEEFVRMM 146
Cdd:NF041410  33 FAKLDSDGDGSVSQDELSSALSSKSDDGSLIDLSELFSDLDSDGDGSLSSDELAAAA 89

centrin; Provisional

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 294948080   4 QLTEEQIAEFKEAFSLFDKDGDGTITTKELGTVMRSLGQNPTEAELQDMINEVDADGNGTIDFPEFLSLMARKMKDTDTE 83
Cdd:PTZ00183  10 GLTEDQKKEIREAFDLFDTDGSGTIDPKELKVAMRSLGFEPKKEEIKQMIADVDKDGSGKIDFEEFLDIMTKKLGERDPR 89

                         90       100       110       120       130       140
                 ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 294948080  84 EELIEAFKVFDRDGNGFISAAELRHVMTNLGEKLTDEEVDEMIREADVDGDGQINYEEFVRMM 146
Cdd:PTZ00183  90 EEILKAFRLFDDDKTGKISLKNLKRVAKELGETITDEELQEMIDEADRNGDGEISEEEFYRIM 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 294948080  85 ELIEAFKVFDRDGNGFISAAELRHVMTNLGEKLTDEEVDEMIREADVDGDGQINYEEFVRMMM 147
Cdd:cd00051    1 ELREAFRLFDKDGDGTISADELKAALKSLGEGLSEEEIDEMIREVDKDGDGKIDFEEFLELMA 63

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 294948080  12 EFKEAFSLFDKDGDGTITTKELGTVMRSLGQNPTEAE-LQDMINEVDADGNGTIDFPEFLSLMarkmkdtDTEEELIEAF 90
Cdd:cd16180    1 ELRRIFQAVDRDRSGRISAKELQRALSNGDWTPFSIEtVRLMINMFDRDRSGTINFDEFVGLW-------KYIQDWRRLF 73

                         90       100       110       120       130
                 ....*....|....*....|....*....|....*....|....*....|....*..
gi 294948080  91 KVFDRDGNGFISAAELRHVMTNLGEKLTDEEVDEMIREADVDGDGQINYEEFVRMMM 147
Cdd:cd16180   74 RRFDRDRSGSIDFNELQNALSSFGYRLSPQFVQLLVRKFDRRRRGSISFDDFVEACV 130

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 294948080  13 FKEAFSLFDKDGDGTITTKELGTVMRSLGQNPTEAELQDMINEVDADGNGTIDFPEFLSLMARKMkdtdTEEELIEAFKV 92
Cdd:cd15898    2 LRRQWIKADKDGDGKLSLKEIKKLLKRLNIRVSEKELKKLFKEVDTNGDGTLTFDEFEELYKSLT----ERPELEPIFKK 77

                         90       100       110       120       130
                 ....*....|....*....|....*....|....*....|....*....|....*..
gi 294948080  93 FDRDGNGFISAAELRHVMTN-LGEKLTDEEVDEMIREADVDG-DGQINYEEFVRMMM 147
Cdd:cd15898   78 YAGTNRDYMTLEEFIRFLREeQGENVSEEECEELIEKYEPEReNRQLSFEGFTNFLL 134

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 294948080  12 EFKEAFSLFDKDGDGTITTKELGTVMRSLGQNPTEAELQDMINEVDADGNGTIDFPEFLSLMA--RKMKDtdteeelieA 89
Cdd:cd16185    1 ELRQWFRAVDRDRSGSIDVNELQKALAGGGLLFSLATAEKLIRMFDRDGNGTIDFEEFAALHQflSNMQN---------G 71

                         90       100       110       120       130
                 ....*....|....*....|....*....|....*....|....*....|....*.
gi 294948080  90 FKVFDRDGNGFISAAELRHVMTNLGEKLTDEEVDEMIREADVDGDGQINYEEFVRM 145
Cdd:cd16185   72 FEQRDTSRSGRLDANEVHEALAASGFQLDPPAFQALFRKFDPDRGGSLGFDDYIEL 127

Ca2+-binding protein, EF-hand superfamily [Signal transduction mechanisms];

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 294948080   2 ADQLTEEQIAEFKEAFSLFDKDGDGTITTKELGTVMRSLGQNPTEAELQDMINEVDADGNGTIDFPEFLSLMARKmkdTD 81
Cdd:COG5126   24 RDDFEALFRRLWATLFSEADTDGDGRISREEFVAGMESLFEATVEPFARAAFDLLDTDGDGKISADEFRRLLTAL---GV 100

                         90       100       110
                 ....*....|....*....|....*....|
gi 294948080  82 TEEELIEAFKVFDRDGNGFISAAELRHVMT 111
Cdd:COG5126  101 SEEEADELFARLDTDGDGKISFEEFVAAVR 130

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 294948080  13 FKEAFSLFDKDGDGTITTKELGTVMRSL-----GQNPTEAELQDMINEV----DADGNGTIDFPEFLSLMA--------- 74
Cdd:cd15902    1 FMEVWMHFDADGNGYIEGKELDSFLRELlkalnGKDKTDDEVAEKKKEFmekyDENEDGKIEIRELANILPteenflllf 80

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 294948080  75 RKMKDTDTEEELIEAFKVFDRDGNGFISAAELRHVMTNLGEKL--------TDEEVDEMIREADVDGDGQINYEEFVRMM 146
Cdd:cd15902   81 RREQPLISSVEFMKIWRKYDTDGSGFIEAKELKGFLKDLLLKNkkhvsppkLDEYTKLILKEFDANKDGKLELDEMAKLL 160

EF-hand, calcium binding motif, found in parvalbumin-like EF-hand family; The family includes alpha- and beta-parvalbumins, and a group of uncharacterized calglandulin-like proteins. Parvalbumins are small, acidic, cytosolic EF-hand-containing Ca2+-buffer and Ca2+ transporter/shuttle proteins belonging to EF-hand superfamily. They are expressed by vertebrates in fast-twitch muscle cells, specific neurons of the central and peripheral nervous system, sensory cells of the mammalian auditory organ (Corti's cell), and some other cells, and characterized by the presence of three consecutive EF-hand motifs (helix-loop-helix) called AB, CD, and EF, but only CD and EF can chelate metal ions, such as Ca2+ and Mg2+. Thus, they may play an additional role in Mg2+ handling. Moreover, parvalbumins represent one of the major animal allergens. In metal-bound states, parvalbumins possess a rigid and stable tertiary structure and display strong allergenicity. In contrast, the metal-free parvalbumins are intrinsically disordered, and the loss of metal ions results in a conformational change that decreases their IgE binding capacity. Furthermore, parvalbumins have been widely used as a neuronal marker for a variety of functional brain systems. They also function as a Ca2+ shuttle transporting Ca2+ from troponin-C (TnC) to the sarcoplasmic reticulum (SR) Ca2+ pump during muscle relaxation. Thus they may facilitate myocardial relaxation and play important roles in cardiac diastolic dysfunction. Parvalbumins consists of alpha- and beta- sublineages, which can be distinguished on the basis of isoelectric point (pI > 5 for alpha; pI

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 294948080  62 GTIDFPEFLSLMARKMKdtdTEEELIEAFKVFDRDGNGFISAAELRHVMTNL---GEKLTDEEVDEMIREADVDGDGQIN 138
Cdd:cd16251   15 GSFNYKKFFEHVGLKQK---SEDQIKKVFQILDKDKSGFIEEEELKYILKGFsiaGRDLTDEETKALLAAGDTDGDGKIG 91

                 ....*..
gi 294948080 139 YEEFVRM 145
Cdd:cd16251   92 VEEFATL 98

EF-hand domain pair;

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 294948080   14 KEAFSLFDKDGDGTITTKELGTVMRSL--GQNPTEAELQDMINEVDADGNGTIDFPEFLSLM 73
Cdd:pfam13499   5 KEAFKLLDSDGDGYLDVEELKKLLRKLeeGEPLSDEEVEELFKEFDLDKDGRISFEEFLELY 66

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 294948080  25 DGTITTKELGTVMRSLG--QNPTEAELQD---MINEVDADGNGTIDFPEFLSLMArkmkdtdTEEELIEAFKVFDRDGNG 99
Cdd:cd16181   13 DGQIDADELQRCLTQSGisGNYQPFSLETcrlMIAMLDRDHSGKMGFNEFKELWA-------ALNQWKTTFMQYDRDRSG 85

                         90       100       110       120
                 ....*....|....*....|....*....|....*....|....
gi 294948080 100 FISAAELRHVMTNLGEKLTDEEVDEMIREADVdgDGQINYEEFV 143
Cdd:cd16181   86 TVEPQELQQAIRSFGYNLSPQALNVIVKRYSK--NGRITFDDFV 127

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 294948080  17 FSLFDKDGDGTITTKEL-GTVMRSLGQNPTEAELQDMINEVDADGNGTIDFPEFLSLMA--RKMKdtdteeeliEAFKVF 93
Cdd:cd16184    6 FQAVDRDRSGKISAKELqQALVNGNWSHFNDETCRLMIGMFDKDKSGTIDIYEFQALWNyiQQWK---------QVFQQF 76

                         90       100       110       120       130
                 ....*....|....*....|....*....|....*....|....*....|
gi 294948080  94 DRDGNGFISAAELRHVMTNLGEKLTDEEVDEMIREADVDGDGQINYEEFV 143
Cdd:cd16184   77 DRDRSGSIDENELHQALSQMGYRLSPQFVQFLVSKYDPRARRSLTLDQFI 126

EF-hand, calcium binding motif, found in reticulocalbin-2 (RCN2) mainly from protostomes; This family corresponds to a group of uncharacterized RCN2-like proteins, which are mainly found in protostomes. Although their biological function remains unclear, they show high sequence similarity with RCN2 (also known as E6BP or TCBP-49), which is an endoplasmic reticulum resident low-affinity Ca2+-binding protein that has been implicated in immunity, redox homeostasis, cell cycle regulation and coagulation. Members in this family contain six copies of the EF-hand Ca2+-binding motif, but may lack a C-terminal His-Asp-Glu-Leu (HDEL) tetrapeptide that is required for retention of RCN2 in the endoplasmic reticulum (ER).

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 294948080  10 IAEFKEAFSLFDKDGDGTITTKELgtvmrSLGQNPTE------AELQDMINEVDADGNGTIDFPEFLSLMArkmKDTDTE 83
Cdd:cd16227  121 LEDDKEMFEAADLNKDGKLDKTEF-----SAFQHPEEyphmhpVLIEQTLRDKDKDNDGFISFQEFLGDRA---GHEDKE 192

                         90       100       110       120       130       140
                 ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 294948080  84 EELIEAFKV---FDRDGNGFISAAELRHVMTNLGEKLTDEEVDEMIREADVDGDGQINYEEFV 143
Cdd:cd16227  193 WLLVEKDRFdedYDKDGDGKLDGEEILSWLVPDNEEIAEEEVDHLFASADDDHDDRLSFDEIL 255

Penta-EF hand, calcium binding motifs, found in PEF calpain family; The PEF calpain family belongs to the second group of penta-EF hand (PEF) proteins. It includes classical (also called conventional or typical) calpain (referring to a calcium-dependent papain-like enzymes, EC 3.4.22.17) large catalytic subunits (CAPN1, 2, 3, 8, 9, 11, 12, 13, 14) and two calpain small subunits (CAPNS1 and CAPNS2), which are largely confined to animals (metazoans). These PEF-containing are nonlysosomal intracellular calcium-activated intracellular cysteine proteases that play important roles in the degradation or functional modulation in a variety of substrates in response to calcium signalling. The classical mu- and m-calpains are heterodimers consisting of homologous but a distinct (large) L-subunit/chain (CAPN1 or CAPN2) and a common (small) S-subunit/chain (CAPNS1 or CAPNS2). These L-subunits (CAPN1 and CAPN2) and S-subunit CAPNS1 are ubiquitously found in all tissues. Other calpains likely consist of an isolated L-subunit/chain alone. Many of them, such as CAPNS2, CAPN3 (in skeletal muscle, or lens), CAPN8 (in stomach), CAPN9 (in digestive tracts), CAPN11 (in testis), CAPN12 (in follicles), are tissue-specific and have specific functions in distinct organs. The L-subunits of similar structure (called CALPA and B) also have been found in Drosophila melanogaster. The S-subunit seems to have a chaperone-like function for proper folding of the L-subunit. The catalytic L-subunits contain 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 S-subunits only have the PEF domain following an N-terminal Gly-rich hydrophobic domain. The calpains undergo a rearrangement of the protein backbone upon Ca2+-binding.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 294948080  18 SLFDK--DGDGTITTKELGTVMRSL--------GQNPTEAELQdMINEVDADGNGTIDFPEFLSLMARKmkdtdteEELI 87
Cdd:cd16182    4 ELFEKlaGEDEEIDAVELQKLLNASllkdmpkfDGFSLETCRS-LIALMDTNGSGRLDLEEFKTLWSDL-------KKWQ 75

                         90       100       110       120       130       140
                 ....*....|....*....|....*....|....*....|....*....|....*....|
gi 294948080  88 EAFKVFDRDGNGFISAAELRHVMTNLGEKLtDEEVDEMIREADVDGDGQINYEEFVRMMM 147
Cdd:cd16182   76 AIFKKFDTDRSGTLSSYELRKALESAGFHL-SNKVLQALVLRYADSTGRITFEDFVSCLV 134

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 294948080  11 AEFKEAFSLFDKDGDGTITTKELGTVMRSL--------GQNPTEAELQDMINEVDADGNGTIDFPEFLSLMARK------ 76
Cdd:cd15902   90 VEFMKIWRKYDTDGSGFIEAKELKGFLKDLllknkkhvSPPKLDEYTKLILKEFDANKDGKLELDEMAKLLPVQenfllk 169

                         90       100       110       120       130       140       150
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 294948080  77 ----MKDTDTEEELIEAFKVFDRDGNGFISAAELRHVMTNLGEKLTDEE--------VDEMIREADVDGDGQINYEEFV 143
Cdd:cd15902  170 fqilGAMDLTKEDFEKVFEHYDKDNNGVIEGNELDALLKDLLEKNKADIdkpdlenfRDAILRACDKNKDGKIQKTELA 248

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 294948080  10 IAEFKEAFSLFDKDGDGTITTKELGTVMRSLGQNPTEAELQDMINEVDADGNGTIDFPEFL-SLMARKMkdtdteeeLIE 88
Cdd:cd16180   66 IQDWRRLFRRFDRDRSGSIDFNELQNALSSFGYRLSPQFVQLLVRKFDRRRRGSISFDDFVeACVTLKR--------LTD 137

                         90
                 ....*....|...
gi 294948080  89 AFKVFDRDGNGFI 101
Cdd:cd16180  138 AFRKYDTNRTGYA 150

EF-hand domain pair;

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|.
gi 294948080   97 GNGFISAAELRHVMTNLGEK-LTDEEVDEMIREADVDGDGQINYEEFVRMM 146
Cdd:pfam13833   1 EKGVITREELKRALALLGLKdLSEDEVDILFREFDTDGDGYISFDEFCVLL 51

EF-hand, calcium binding motif, found in alpha-parvalbumin; Alpha-parvalbumin is cytosolic Ca2+/Mg2+-binding protein expressed mainly in fast-twitch skeletal myofibrils, where it may act as a soluble relaxing factor facilitating the Ca2+-mediated relaxation phase. It is also expressed in rapidly firing neurons, particularly GABA-ergic neurons, and thus may confer protection against Ca2+ toxicity. The major role of alpha-parvalbumin is metal buffering and transport of Ca2+. It binds different metal cations, and exhibits very high affinity for Ca2+ and physiologically significant affinity for Mg2+. Alpha-parvalbumin is characterized by the presence of three consecutive EF-hand motifs (helix-loop-helix) called AB, CD, and EF, but only CD and EF can chelate metal ions, such as Ca2+ and Mg2+. Both metal ion-binding sites in alpha-parvalbumin are high-affinity sites. Additionally, in contrast to beta-parvalbumin, alpha-parvalbumin is less acidic and has an additional residue in the C-terminal helix.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 294948080  62 GTIDFPEFLSLMARKMKdtdTEEELIEAFKVFDRDGNGFISAAELRHVMTNL---GEKLTDEEVDEMIREADVDGDGQIN 138
Cdd:cd16254   15 DSFDYKKFFEMVGLKKK---SADDVKKVFHILDKDKSGFIEEDELKFVLKGFspdGRDLSDKETKALLAAGDKDGDGKIG 91

                 ....*...
gi 294948080 139 YEEFVRMM 146
Cdd:cd16254   92 IDEFATLV 99

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 294948080  52 MINEVDADGNGTIDFPEFLSLMARKMKDTDTeeelieaFKVFDRDGNGFISAAELRHVMTNLGEKLTDEEVDEM-IREAD 130
Cdd:cd16195   48 MVALMDLSVNGRLSLEEFSRLWKKLRKYKDI-------FQKADVSKSGFLSLSELRNAIQAAGIRVSDDLLNLMaLRYGD 120

                         90
                 ....*....|....*..
gi 294948080 131 VdgDGQINYEEFVRMMM 147
Cdd:cd16195  121 S--SGRISFESFICLML 135

EF-hand, calcium binding motif, found in calbindin (CB); CB, also termed calbindin D28, or D-28K, or avian-type vitamin D-dependent calcium-binding protein, is a unique intracellular calcium binding protein that functions as both a calcium sensor and buffer in eukaryotic cells, which undergoes a conformational change upon calcium binding and protects cells against insults of high intracellular calcium concentration. CB is highly expressed in brain and sensory neurons. It plays essential roles in neural functioning, altering synaptic interactions in the hippocampus, modulating calcium channel activity, calcium transients, and intrinsic neuronal firing activity. It prevents a neuronal death, as well as maintains and controls calcium homeostasis. CB also modulates the activity of proteins participating in the development of neurodegenerative disorders such as Alzheimer's disease, Huntington's disease, and bipolar disorder. Moreover, CB interacts with Ran-binding protein M, a protein known to involve in microtubule function. It also interacts with alkaline phosphatase and myo-inositol monophosphatase, as well as caspase 3, an enzyme that plays an important role in the regulation of apoptosis. CB contains six EF-hand motifs in a single globular domain, where EF-hands 1, 3, 4, 5 bind four calcium ions with high affinity.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 294948080  13 FKEAFSLFDKDGDGTITTKELGTVMRSLGQNPTEA------ELQDMINEVDADGNGTIDFPE----------FLSLMARK 76
Cdd:cd16176    1 FLEIWHHYDNDGNGYIEGKELQSFIQELQQARKKAglelsdQMKAFVDQYGQSTDGKIGIVElaqilpteenFLLFFRQQ 80

                         90       100       110       120       130       140       150
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 294948080  77 MKDTdteEELIEAFKVFDRDGNGFISAAELRHVMTNLGEKLT--------DEEVDEMIREADVDGDGQINYEEFVRMM 146
Cdd:cd16176   81 LKSS---EEFMQTWRKYDADHSGFIEADELKSFLKDLLKKANkpfdesklEEYTHTMLKMFDSNNDGKLGLTEMARLL 155

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 294948080  10 IAEFKEAFSLFDKDGDGTITTKELGTVMRSLGQNPTEaELQDMINEVDADGNGTIDFPEFLSLMARKmkdtdteEELIEA 89
Cdd:cd15897   69 IKAWQEIFRTYDTDGSGTIDSNELRQALSGAGYRLSE-QTYDIIIRRYDRGRGNIDFDDFIQCCVRL-------QRLTDA 140

                         90
                 ....*....|..
gi 294948080  90 FKVFDRDGNGFI 101
Cdd:cd15897  141 FRRYDKDQDGQI 152

Eps15 homology domain; Pair of EF hand motifs that recognise proteins containing Asn-Pro-Phe (NPF) sequences.

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 294948080     5 LTEEQIAEFKEAFSLFDKDGDGTITTKELGTVMRSLGQNPTeaELQDMINEVDADGNGTIDFPEF---LSLMARKM 77
Cdd:smart00027   4 ISPEDKAKYEQIFRSLDKNQDGTVTGAQAKPILLKSGLPQT--LLAKIWNLADIDNDGELDKDEFalaMHLIYRKL 77

EF-hand domain;

                          10        20        30
                  ....*....|....*....|....*....|
gi 294948080   85 ELIEAFKVFDRDGNGFISAAELRHVMTNLG 114
Cdd:pfam13405   1 ELREAFKLFDKDGDGKISLEELRKALRSLG 30

Eps15 homology domain; found in proteins implicated in endocytosis, vesicle transport, and signal transduction. The alignment contains a pair of EF-hand motifs, typically one of them is canonical and binds to Ca2+, while the other may not bind to Ca2+. A hydrophobic binding pocket is formed by residues from both EF-hand motifs. The EH domain binds to proteins containing NPF (class I), [WF]W or SWG (class II), or H[TS]F (class III) sequence motifs.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*.
gi 294948080  88 EAFKVFDRDGNGFISAAELRHVMTNLGekLTDEEVDEMIREADVDGDGQINYEEFV 143
Cdd:cd00052    3 QIFRSLDPDGDGLISGDEARPFLGKSG--LPRSVLAQIWDLADTDKDGKLDKEEFA 56

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 294948080    12 EFKEAFSLFDKDGDGTITTKELGTVMRSL 40
Cdd:smart00054   1 ELKEAFRLFDKDGDGKIDFEEFKDLLKAL 29

EF-hand domain pair;

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 294948080   24 GDGTITTKELGTVMRSLG-QNPTEAELQDMINEVDADGNGTIDFPEFLSLMAR 75
Cdd:pfam13833   1 EKGVITREELKRALALLGlKDLSEDEVDILFREFDTDGDGYISFDEFCVLLER 53

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 294948080  10 IAEFKEAFSLFDKDGDGTITTKELGTVMRSLGQNPTEaELQDMINEVDADGNGTIDFPEFLSLMARKmkdtdteEELIEA 89
Cdd:cd16188   72 IKKWQGIYKQFDTDRSGTIGSQELPGAFEAAGFHLNE-QLYQMIIRRYSDEDGNMDFDNFISCLVRL-------DAMFRA 143

                         90
                 ....*....|..
gi 294948080  90 FKVFDRDGNGFI 101
Cdd:cd16188  144 FKSLDKDGTGQI 155

EF-hand, calcium binding motif, found in uncharacterized calglandulin-like proteins; The family corresponds to a group of uncharacterized calglandulin-like proteins. Although their biological function remain unclear, they show high sequence similarity with human calglandulin-like protein GAGLP, which is an ortholog of calglandulin from the venom glands of Bothrops insularis snake. Both GAGLP and calglandulin are putative Ca2+-binding proteins with four EF-hand motifs. However, members in this family contain only three EF-hand motifs. In this point, they may belong to the parvalbumin-like EF-hand family, which is characterized by the presence of three consecutive EF-hand motifs (helix-loop-helix).

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 294948080   4 QLTEEQIAEFKEAFSLFDKDGDGTITTKE----LGTVMRSLGQNP-TEAELQDMINEVDADGNGTIDFPEF 69
Cdd:cd16252   30 QTSEQQEEAIRKAFQMLDKDKSGFIEWNEikyiLSTVPSSMPVAPlSDEEAEAMIQAADTDGDGRIDFQEF 100