SPL-RING finger found in E3 SUMO-protein ligase NSE2 and similar proteins; NSE2, also known as MMS21 homolog (MMS21) or non-structural maintenance of chromosomes element 2 homolog (Non-SMC element 2 homolog, NSMCE2), is an autosumoylating small ubiquitin-like modifier (SUMO) ligase required for the response to DNA damage. It regulates sumoylation and nuclear-to-cytoplasmic translocation of skeletal and heart muscle-specific variant of the alpha subunit of nascent polypeptide associated complex (skNAC)-Smyd1 in myogenesis. It is also required for resisting extrinsically induced genotoxic stress. Moreover, NSE2 together with its partner proteins SMC6 and SMC5 form a tight subcomplex of the structural maintenance of chromosomes SMC5-6 complex, which includes another two subcomplexes, NSE1-NSE3-NSE4 and NSE5-NSE6. SMC6 and NSE3 are sumoylated in an NSE2-dependent manner, but SMC5 and NSE1 are not. NSE2-dependent E3 SUMO ligase activity is required for efficient DNA repair, but not for SMC5-6 complex stability. NSE2 contains a RING variant known as a Siz/PIAS (protein inhibitor of activated signal transducer and activator of transcription)-like RING (SPL-RING) finger that is likely shared by the SP-RING type SUMO E3 ligases, such as PIAS family proteins. The SPL-RING finger is a variant of the RING finger, which lacks the second, fifth, and sixth zinc-binding residues of the consensus C3H2C3-/C3HC4-type RING fingers. It harbors only one Zn binding site and is required for the sumoylating activity.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1162503620 167 FTCPITKEEMKKPVKNKVCGHTYEEDAIVRMIesrQKRKKKAYCPQIGCSHTdIRKSDLIQDEALRRAIEN 237
Cdd:cd16651     1 LKCPITQQLMVDPVRNKKCGHTYEKAAILQYL---QSRKKKAKCPVAGCRNT-VSKSDLVPDPELKRRIER 67

SPL-RING finger found in E3 SUMO-protein ligase NSE2 and similar proteins; NSE2, also known as MMS21 homolog (MMS21) or non-structural maintenance of chromosomes element 2 homolog (Non-SMC element 2 homolog, NSMCE2), is an autosumoylating small ubiquitin-like modifier (SUMO) ligase required for the response to DNA damage. It regulates sumoylation and nuclear-to-cytoplasmic translocation of skeletal and heart muscle-specific variant of the alpha subunit of nascent polypeptide associated complex (skNAC)-Smyd1 in myogenesis. It is also required for resisting extrinsically induced genotoxic stress. Moreover, NSE2 together with its partner proteins SMC6 and SMC5 form a tight subcomplex of the structural maintenance of chromosomes SMC5-6 complex, which includes another two subcomplexes, NSE1-NSE3-NSE4 and NSE5-NSE6. SMC6 and NSE3 are sumoylated in an NSE2-dependent manner, but SMC5 and NSE1 are not. NSE2-dependent E3 SUMO ligase activity is required for efficient DNA repair, but not for SMC5-6 complex stability. NSE2 contains a RING variant known as a Siz/PIAS (protein inhibitor of activated signal transducer and activator of transcription)-like RING (SPL-RING) finger that is likely shared by the SP-RING type SUMO E3 ligases, such as PIAS family proteins. The SPL-RING finger is a variant of the RING finger, which lacks the second, fifth, and sixth zinc-binding residues of the consensus C3H2C3-/C3HC4-type RING fingers. It harbors only one Zn binding site and is required for the sumoylating activity.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1162503620 167 FTCPITKEEMKKPVKNKVCGHTYEEDAIVRMIesrQKRKKKAYCPQIGCSHTdIRKSDLIQDEALRRAIEN 237
Cdd:cd16651     1 LKCPITQQLMVDPVRNKKCGHTYEKAAILQYL---QSRKKKAKCPVAGCRNT-VSKSDLVPDPELKRRIER 67

SUMO ligase MMS21, Smc5/6 complex, required for cell growth and DNA repair [Replication, recombination and repair];

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1162503620 142 LQADREADGTEGVDEDIIVTQSQTNFTCPITKEEMKKPVKNKVCGHTYEEDAIVRMIESRQKRKkkayCPQIGCSHTDIR 221
Cdd:COG5627   165 NIVMKSPNPEEGLVDKILIHQELLSNRCPITLNPDFYPILSSKCNHKPEMDLINKKLQVECTRV----CPRLICSQKEVV 240

                          90
                  ....*....|..
gi 1162503620 222 kSDLIQDEALRR 233
Cdd:COG5627   241 -DPYVCDHILEK 251

SPL-RING finger found in E3 SUMO-protein ligase NSE2 and similar proteins; NSE2, also known as MMS21 homolog (MMS21) or non-structural maintenance of chromosomes element 2 homolog (Non-SMC element 2 homolog, NSMCE2), is an autosumoylating small ubiquitin-like modifier (SUMO) ligase required for the response to DNA damage. It regulates sumoylation and nuclear-to-cytoplasmic translocation of skeletal and heart muscle-specific variant of the alpha subunit of nascent polypeptide associated complex (skNAC)-Smyd1 in myogenesis. It is also required for resisting extrinsically induced genotoxic stress. Moreover, NSE2 together with its partner proteins SMC6 and SMC5 form a tight subcomplex of the structural maintenance of chromosomes SMC5-6 complex, which includes another two subcomplexes, NSE1-NSE3-NSE4 and NSE5-NSE6. SMC6 and NSE3 are sumoylated in an NSE2-dependent manner, but SMC5 and NSE1 are not. NSE2-dependent E3 SUMO ligase activity is required for efficient DNA repair, but not for SMC5-6 complex stability. NSE2 contains a RING variant known as a Siz/PIAS (protein inhibitor of activated signal transducer and activator of transcription)-like RING (SPL-RING) finger that is likely shared by the SP-RING type SUMO E3 ligases, such as PIAS family proteins. The SPL-RING finger is a variant of the RING finger, which lacks the second, fifth, and sixth zinc-binding residues of the consensus C3H2C3-/C3HC4-type RING fingers. It harbors only one Zn binding site and is required for the sumoylating activity.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1162503620 167 FTCPITKEEMKKPVKNKVCGHTYEEDAIVRMIesrQKRKKKAYCPQIGCSHTdIRKSDLIQDEALRRAIEN 237
Cdd:cd16651     1 LKCPITQQLMVDPVRNKKCGHTYEKAAILQYL---QSRKKKAKCPVAGCRNT-VSKSDLVPDPELKRRIER 67

SP-RING finger and SPL-RING finger, variants of RING fingers; This family corresponds to a group of proteins with variants of RING fingers that are characterized by lacking the second, fifth, and sixth Zn2+ ion-coordinating residues compared with the classic C3H2C3-/C3HC4-type RING fingers. They include SP-RING finger found in the Siz/PIAS RING (SP-RING) family of SUMO E3 ligases and SPL-RING finger found in E3 SUMO-protein ligase NSE2. The SP-RING family includes PIAS (protein inhibitor of activated STAT) proteins, Zmiz proteins, and Siz proteins from plants and fungi. The PIAS (protein inhibitor of activated STAT) protein family modulates the activity of several transcription factors and acts as an E3 ubiquitin ligase in the sumoylation pathway. NSE2, also known as MMS21 homolog (MMS21) or non-structural maintenance of chromosomes element 2 homolog (Non-SMC element 2 homolog, NSMCE2), is an autosumoylating small ubiquitin-like modifier (SUMO) ligase required for the response to DNA damage. It regulates sumoylation and nuclear-to-cytoplasmic translocation of skeletal and heart muscle-specific variant of the alpha subunit of nascent polypeptide associated complex (skNAC)-Smyd1 in myogenesis. It is also required for resisting extrinsically induced genotoxic stress.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*
gi 1162503620 167 FTCPITKEEMKKPVKNKVCGHTYEEDAIVRMIESRQKRKKkayCP 211
Cdd:cd16452     1 LKCPITQKRMKDPVRGKHCGHCFDLEAILQYLKRRKKKWK---CP 42

RING-type zinc-finger; This zinc-finger is a typical RING-type of plant ubiquitin ligases.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|...
gi 1162503620 169 CPITKEEMKKPVKNkvCGHTYEEDAIVRMiesRQKRKKKAYCP 211
Cdd:pfam13445   1 CPICLELFTDPVLP--CGHTFCRECLEEM---SQKKGGKFKCP 38

Modified RING finger domain; Modified RING finger domain, without the full complement of Zn2+-binding ligands. Probable involvement in E2-dependent ubiquitination.

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1162503620  167 FTCPITKEEMKKPVKNKVcGHTYEEDAIVRMIESRQKrkkkayCPqigCSHTDIRKSDLIQDEALRRAIE 236
Cdd:smart00504   2 FLCPISLEVMKDPVILPS-GQTYERSAIEKWLLSHGT------DP---VTGQPLTHEDLIPNLALKSAIQ 61

U-box domain, a modified RING finger, found in Arabidopsis plant U-box proteins (AtPUB) and similar proteins; The plant PUB proteins, also known as U-box domain-containing proteins, are much more numerous in Arabidopsis which has 62 in comparison with the typical 6 in most animals. The majority of AtPUBs in this subfamily are known as ARM domain-containing PUB proteins, containing a C-terminally-located, tandem ARM (armadillo) repeat protein-interaction region in addition to the U-box domain. They have been implicated in the regulation of cell death and defense. They also play important roles in other plant-specific pathways, such as controlling both self-incompatibility and pseudo-self-incompatibility, as well as acting in abiotic stress. A subgroup of ARM domain-containing PUB proteins harbors a plant-specific U-box N-terminal domain.

                          10        20        30
                  ....*....|....*....|....*....|....*
gi 1162503620 167 FTCPITKEEMKKPVknKVC-GHTYEEDAIVRMIES 200
Cdd:cd16664     4 FICPISLELMKDPV--ILAtGQTYERAAIEKWLDS 36

first U-box domain, a modified RING finger, found in Legionella pneumophila U-box protein LubX and similar proteins; LubX, also called RING-type E3 ubiquitin transferase LubX, is part of the large arsenal of effectors in Legionella pneumophila that are translocated into the host cytosol during infection. LubX acts as an E3 ubiquitin-protein ligase (EC 2.3.2.27) that interferes with the host's ubiquitination pathway. LubX contains two RING-like U-box domains. U-box 1 is critical to the ubiquitin ligase activity, and U-box 2 mediates interaction with host target. This model corresponds to the first one.

                          10        20        30
                  ....*....|....*....|....*....|....*
gi 1162503620 167 FTCPITKEEMKKPVKNKvCGHTYEEDAIVRMIESR 201
Cdd:cd23149     1 FTCPITSGFMEDPVITP-SGFSYERSAIERWLETK 34

U-box domain, a modified RING finger; The U-box protein family is a family of E3 enzymes that also includes the HECT family and the RING finger family. The E3 enzyme is ubiquitin-protein ligase that cooperates with a ubiquitin-activating enzyme (E1) and a ubiquitin-conjugating enzyme (E2), and plays a central role in determining the specificity of the ubiquitination system. It removes the ubiquitin molecule from the E2 enzyme and attaches it to the target substrate, forming a covalent bond between ubiquitin and the target. U-box proteins are characterized by the presence of a U-box domain of approximately 70 amino acids. The U-box is a modified form of the RING finger domain that lacks metal chelating cysteines and histidines. It resembles the cross-brace RING structure consisting of three beta-sheets and a single alpha-helix, which would be stabilized by salt bridges instead of chelated metal ions. U-box proteins are widely distributed among eukaryotic organisms and show a higher prevalence in plants than in other organisms.

                          10        20        30
                  ....*....|....*....|....*....|....
gi 1162503620 167 FTCPITKEEMKKPVKNKvCGHTYEEDAIVRMIES 200
Cdd:cd16453     1 FLCPISGELMKDPVITP-SGITYDRSAIERWLLS 33

Degenerated RING finger found in protein RMD5 homolog A (RMD5A); RMD5A is one of the vertebrate homologs of yeast Rmd5p. The biological function of RMD5A remains unclear. RMD5A contains a Lissencephaly type-1-like homology motif (LisH), a C-terminal to LisH motif (CTLH) domain, and a degenerated RING finger that is characterized by lacking the second, fifth, and sixth Zn2+ ion-coordinating residues compared with the classic C3H2C3-/C3HC4-type RING fingers.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*..
gi 1162503620 167 FTCPITKEEMKK--PVKNKVCGHTYEEDAIVRMIESrqKRKKKAYCP 211
Cdd:cd16794     3 FACPILRQQTTEnnPPMKLVCGHIISRDALNKMFNG--SKLKCPYCP 47

U-box domain, a modified RING finger, found in carboxyl terminus of HSP70-interacting protein (CHIP) and similar proteins; CHIP, also known as STIP1 homology and U box-containing protein 1 (STUB1), CLL-associated antigen KW-8, or Antigen NY-CO-7, is a multifunctional protein that functions both as a co-chaperone and an E3 ubiquitin-protein ligase. It couples protein folding and proteasome mediated degradation by interacting with heat shock proteins (e.g. HSC70) and ubiquitinating their misfolded client proteins, thereby targeting them for proteasomal degradation. It is also important for cellular differentiation and survival (or apoptosis), as well as susceptibility to stress. It targets a wide range of proteins, such as expanded ataxin-1, ataxin-3, huntingtin, and androgen receptor, which play roles in glucocorticoid response, tau degradation, and both p53 and cAMP signaling. CHIP contains an N-terminal tetratricopeptide repeat (TPR) domain responsible for protein-protein interaction, a highly charged middle coiled-coil (CC), and a C-terminal RING-like U-box domain acting as an ubiquitin ligase.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1162503620 167 FTCPITKEEMKKPVKNKvCGHTYEEDAIVRMIesrqkRKKKAYCPqigCSHTDIRKSDLIQDEALRRAIEN 237
Cdd:cd16654     5 LCCKISFELMRDPVITP-SGITYERKDIEEHL-----QRVGHFDP---ITREPLTQDQLIPNLALKEAIEA 66