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

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 156101878   7 EEQISEFKEAFSLFDKDGDGTITTKELGTVMRslgqnpteAELQDMINEIDTDGNGTIDFPEFLTLMARKMKDTDtEEEL 86
Cdd:COG5126    1 DLQRRKLDRRFDLLDADGDGVLERDDFEALFR--------RLWATLFSEADTDGDGRISREEFVAGMESLFEATV-EPFA 71

                         90       100       110       120       130       140
                 ....*....|....*....|....*....|....*....|....*....|....*....|
gi 156101878  87 IEAFRVFDRDGDGYISADELRHVMTNLGekLTNEEVDEMIREADIDGDGQINYEEFVKMM 146
Cdd:COG5126   72 RAAFDLLDTDGDGKISADEFRRLLTALG--VSEEEADELFARLDTDGDGKISFEEFVAAV 129

EF-hand domain pair;

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 156101878   83 EEELIEAFRVFDRDGDGYISADELRHVMTNL--GEKLTNEEVDEMIREADIDGDGQINYEEFVKMM 146
Cdd:pfam13499   1 EEKLKEAFKLLDSDGDGYLDVEELKKLLRKLeeGEPLSDEEVEELFKEFDLDKDGRISFEEFLELY 66

XopAW family type III secretion system calcium-binding effector;

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 156101878  39 SLGQNPTEAELQ-DMINEIDTDGNGTIDFPEFLTLMARKmKDTDTEEELIEAFRVFDRDGDGYISADELRHVMTN----L 113
Cdd:NF041410  18 SSTSSARSQQFQkQLFAKLDSDGDGSVSQDELSSALSSK-SDDGSLIDLSELFSDLDSDGDGSLSSDELAAAAPPppppP 96

                         90       100
                 ....*....|....*....|....*....
gi 156101878 114 GEKLTNEEVDEMIREADIDGDGQINYEEF 142
Cdd:NF041410  97 DQAPSTELADDLLSALDTDGDGSISSDEL 125

XopAW family type III secretion system calcium-binding effector;

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*..
gi 156101878  90 FRVFDRDGDGYISADELRHVMTNLGEKLTNEEVDEMIREADIDGDGQINYEEFVKMM 146
Cdd:NF041410  33 FAKLDSDGDGSVSQDELSSALSSKSDDGSLIDLSELFSDLDSDGDGSLSSDELAAAA 89

centrin; Provisional

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 156101878   5 LTEEQISEFKEAFSLFDKDGDGTITTKELGTVMRSLGQNPTEAELQDMINEIDTDGNGTIDFPEFLTLMARKMKDTDTEE 84
Cdd:PTZ00183  11 LTEDQKKEIREAFDLFDTDGSGTIDPKELKVAMRSLGFEPKKEEIKQMIADVDKDGSGKIDFEEFLDIMTKKLGERDPRE 90

                         90       100       110       120       130       140
                 ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 156101878  85 ELIEAFRVFDRDGDGYISADELRHVMTNLGEKLTNEEVDEMIREADIDGDGQINYEEFVKMM 146
Cdd:PTZ00183  91 EILKAFRLFDDDKTGKISLKNLKRVAKELGETITDEELQEMIDEADRNGDGEISEEEFYRIM 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 156101878  85 ELIEAFRVFDRDGDGYISADELRHVMTNLGEKLTNEEVDEMIREADIDGDGQINYEEFVKMM 146
Cdd:cd00051    1 ELREAFRLFDKDGDGTISADELKAALKSLGEGLSEEEIDEMIREVDKDGDGKIDFEEFLELM 62

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 156101878  12 EFKEAFSLFDKDGDGTITTKELGTVMRSLGQNPTEAE-LQDMINEIDTDGNGTIDFPEFLTLMarkmkdtDTEEELIEAF 90
Cdd:cd16180    1 ELRRIFQAVDRDRSGRISAKELQRALSNGDWTPFSIEtVRLMINMFDRDRSGTINFDEFVGLW-------KYIQDWRRLF 73

                         90       100       110       120       130
                 ....*....|....*....|....*....|....*....|....*....|....*..
gi 156101878  91 RVFDRDGDGYISADELRHVMTNLGEKLTNEEVDEMIREADIDGDGQINYEEFVKMMI 147
Cdd:cd16180   74 RRFDRDRSGSIDFNELQNALSSFGYRLSPQFVQLLVRKFDRRRRGSISFDDFVEACV 130

EF-hand domain pair;

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 156101878   83 EEELIEAFRVFDRDGDGYISADELRHVMTNL--GEKLTNEEVDEMIREADIDGDGQINYEEFVKMM 146
Cdd:pfam13499   1 EEKLKEAFKLLDSDGDGYLDVEELKKLLRKLeeGEPLSDEEVEELFKEFDLDKDGRISFEEFLELY 66

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 156101878  17 FSLFDKDGDGTITTKELGTVMrSLGQ----NPTEAELqdMINEIDTDGNGTIDFPEFLTLMARKmkdTDTEEelieAFRV 92
Cdd:cd16183    6 FQRVDKDRSGQISATELQQAL-SNGTwtpfNPETVRL--MIGMFDRDNSGTINFQEFAALWKYI---TDWQN----CFRS 75

                         90       100       110       120       130
                 ....*....|....*....|....*....|....*....|....*....|.
gi 156101878  93 FDRDGDGYISADELRHVMTNLGEKLTNEEVDEMIREADIDGDGQINYEEFV 143
Cdd:cd16183   76 FDRDNSGNIDKNELKQALTSFGYRLSDQFYDILVRKFDRQGRGTIAFDDFI 126

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 156101878  13 FKEAFSLFDKDGDGTITTKELGTVMRSL-----GQNPTEAELQDMINEI----DTDGNGTIDFPEFLTLMA--------- 74
Cdd:cd15902    1 FMEVWMHFDADGNGYIEGKELDSFLRELlkalnGKDKTDDEVAEKKKEFmekyDENEDGKIEIRELANILPteenflllf 80

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 156101878  75 RKMKDTDTEEELIEAFRVFDRDGDGYISADELRHVMTNLGEKL--------TNEEVDEMIREADIDGDGQINYEEFVKMM 146
Cdd:cd15902   81 RREQPLISSVEFMKIWRKYDTDGSGFIEAKELKGFLKDLLLKNkkhvsppkLDEYTKLILKEFDANKDGKLELDEMAKLL 160

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

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 156101878  49 LQDMINEIDTDGNGTIDFPEFLTLMARKMKDTdteeelieaFRVFDRDGDGYISADELRHVMTNLGEKLTNEEVDEMIRE 128
Cdd:COG5126    7 LDRRFDLLDADGDGVLERDDFEALFRRLWATL---------FSEADTDGDGRISREEFVAGMESLFEATVEPFARAAFDL 77

                         90       100
                 ....*....|....*....|
gi 156101878 129 ADIDGDGQINYEEFVKMMIA 148
Cdd:COG5126   78 LDTDGDGKISADEFRRLLTA 97

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        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 156101878  62 GTIDFPEFLTLMARKMKDTDTEEELIEAFRVFDRDGDGYISADELRHVMTNLGEK-----LTNEEVDEMIREADIDGDGQ 136
Cdd:cd16252   15 GSFNYSKFFEYMQKFQTSEQQEEAIRKAFQMLDKDKSGFIEWNEIKYILSTVPSSmpvapLSDEEAEAMIQAADTDGDGR 94

                 ....*....
gi 156101878 137 INYEEFVKM 145
Cdd:cd16252   95 IDFQEFSDM 103

EF-hand domain pair;

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 156101878   10 ISEFKEAFSLFDKDGDGTITTKELGTVMRSL--GQNPTEAELQDMINEIDTDGNGTIDFPEFLTLM 73
Cdd:pfam13499   1 EEKLKEAFKLLDSDGDGYLDVEELKKLLRKLeeGEPLSDEEVEELFKEFDLDKDGRISFEEFLELY 66

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 156101878  62 GTIDFPEFLTLMARKMKdtdTEEELIEAFRVFDRDGDGYISADELRHVMTNL---GEKLTNEEVDEMIREADIDGDGQIN 138
Cdd:cd16251   15 GSFNYKKFFEHVGLKQK---SEDQIKKVFQILDKDKSGFIEEEELKYILKGFsiaGRDLTDEETKALLAAGDTDGDGKIG 91

                 ....*..
gi 156101878 139 YEEFVKM 145
Cdd:cd16251   92 VEEFATL 98

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 156101878  18 SLFDK--DGDGTITTKELGTVMRSL--------GQNPTEAELQdMINEIDTDGNGTIDFPEFLTLMARKmkdtdteEELI 87
Cdd:cd16182    4 ELFEKlaGEDEEIDAVELQKLLNASllkdmpkfDGFSLETCRS-LIALMDTNGSGRLDLEEFKTLWSDL-------KKWQ 75

                         90       100       110       120       130
                 ....*....|....*....|....*....|....*....|....*....|....*.
gi 156101878  88 EAFRVFDRDGDGYISADELRHVMTNLGEKLTNeEVDEMIREADIDGDGQINYEEFV 143
Cdd:cd16182   76 AIFKKFDTDRSGTLSSYELRKALESAGFHLSN-KVLQALVLRYADSTGRITFEDFV 130

XopAW family type III secretion system calcium-binding effector;

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 156101878  39 SLGQNPTEAELQ-DMINEIDTDGNGTIDFPEFLTLMARKmKDTDTEEELIEAFRVFDRDGDGYISADELRHVMTN----L 113
Cdd:NF041410  18 SSTSSARSQQFQkQLFAKLDSDGDGSVSQDELSSALSSK-SDDGSLIDLSELFSDLDSDGDGSLSSDELAAAAPPppppP 96

                         90       100
                 ....*....|....*....|....*....
gi 156101878 114 GEKLTNEEVDEMIREADIDGDGQINYEEF 142
Cdd:NF041410  97 DQAPSTELADDLLSALDTDGDGSISSDEL 125

N-terminal domain of Myosin essential light chain ELC; ELC is part of the apicomplexan membrane-associated protein complex called the glideosome, which is essential for parasite motility. The glideosome is composed of six proteins: myosin A (MyoA), essential light chain ELC, myosin light chain MLC1 (also called MTIP), and the glideosome-associated proteins GAP40, GAP45, and GAP50. MyoA is a Class XIV myosin implicated in gliding motility, as well as host cell and tissue invasion by parasites. ELC binds to the MyoA neck region adjacent to the MLC1-binding site, and both myosin light chains co-located to the glideosome. Although ELCs bind to a conserved MyoA sequence, P. falciparum ELC adopts a distinct structure in the free and MyoA-bound state. Therefore ELCs enhance MyoA performance by inducing alpha helical structure formation in MyoA and thus stiffening its lever arm. It has been shown that disruption of MyoA, MLC1, or ELC have dramatic effects on parasite motility but do not affect parasite shape or replication. The ELC N-terminal domain is part of the EF-hand calcium binding motif superfamily. Calcium binding has no effect on the structure of ELCs.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 156101878  13 FKEAFSLFDKDGDGTITTKELGTVMRSLGQNPTEAELQDMINeidtdgngTIDFPEFLTLMARKMKDTD 81
Cdd:cd22949    5 FREAFILFDRDGDGELTMYEAVLAMRSCGIPLTNDEKDALPA--------SMNWDQFENWAKKKLAYSD 65

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 156101878  25 DGTITTKELGTVMRSLG--QNPTEAELQD---MINEIDTDGNGTIDFPEFLTLMArkmkdtdTEEELIEAFRVFDRDGDG 99
Cdd:cd16181   13 DGQIDADELQRCLTQSGisGNYQPFSLETcrlMIAMLDRDHSGKMGFNEFKELWA-------ALNQWKTTFMQYDRDRSG 85

                         90       100       110       120
                 ....*....|....*....|....*....|....*....|....
gi 156101878 100 YISADELRHVMTNLGEKLTNEEVDEMIREADIdgDGQINYEEFV 143
Cdd:cd16181   86 TVEPQELQQAIRSFGYNLSPQALNVIVKRYSK--NGRITFDDFV 127

EF-hand domain pair;

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|.
gi 156101878   97 GDGYISADELRHVMTNLGEK-LTNEEVDEMIREADIDGDGQINYEEFVKMM 146
Cdd:pfam13833   1 EKGVITREELKRALALLGLKdLSEDEVDILFREFDTDGDGYISFDEFCVLL 51

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 156101878  12 EFKEAFSLFDKDGDGTITTKELGTVMRSL--GQNPT--EAELQDMINEI----DTDGNGTIDFPEFLTLMARK------- 76
Cdd:cd15902   91 EFMKIWRKYDTDGSGFIEAKELKGFLKDLllKNKKHvsPPKLDEYTKLIlkefDANKDGKLELDEMAKLLPVQenfllkf 170

                         90       100       110       120       130       140       150
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 156101878  77 ---MKDTDTEEELIEAFRVFDRDGDGYISADELRHVMTNLGEKLTNEE--------VDEMIREADIDGDGQINYEEFV 143
Cdd:cd15902  171 qilGAMDLTKEDFEKVFEHYDKDNNGVIEGNELDALLKDLLEKNKADIdkpdlenfRDAILRACDKNKDGKIQKTELA 248

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 156101878  88 EAFRVFDRDGDGYISADELRHVMTNLGekLTNEEVDEMIREADIDGDGQINYEEFV 143
Cdd:cd00052    3 QIFRSLDPDGDGLISGDEARPFLGKSG--LPRSVLAQIWDLADTDKDGKLDKEEFA 56

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 156101878  13 FKEAFSLFDKDGDGTITTKELGTVMRSLGQNPTEA------ELQDMINEIDTDGNGTIDFPE----------FLTLMARK 76
Cdd:cd16176    1 FLEIWHHYDNDGNGYIEGKELQSFIQELQQARKKAglelsdQMKAFVDQYGQSTDGKIGIVElaqilpteenFLLFFRQQ 80

                         90       100       110       120       130       140       150
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 156101878  77 MKDTdteEELIEAFRVFDRDGDGYISADELRHVMTNLGEKlTNEEVDE---------MIREADIDGDGQINYEEFVKMM 146
Cdd:cd16176   81 LKSS---EEFMQTWRKYDADHSGFIEADELKSFLKDLLKK-ANKPFDEskleeythtMLKMFDSNNDGKLGLTEMARLL 155

EF-hand domain;

                          10        20        30
                  ....*....|....*....|....*....|
gi 156101878   85 ELIEAFRVFDRDGDGYISADELRHVMTNLG 114
Cdd:pfam13405   1 ELREAFKLFDKDGDGKISLEELRKALRSLG 30

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 156101878  62 GTIDFPEFLTLMARKMKdtdTEEELIEAFRVFDRDGDGYISADELRHVMTNL---GEKLTNEEVDEMIREADIDGDGQIN 138
Cdd:cd16254   15 DSFDYKKFFEMVGLKKK---SADDVKKVFHILDKDKSGFIEEDELKFVLKGFspdGRDLSDKETKALLAAGDKDGDGKIG 91

                 ....*...
gi 156101878 139 YEEFVKMM 146
Cdd:cd16254   92 IDEFATLV 99

EF-hand, calcium binding motif, found in Drosophila melanogaster calbindin-32 (CBN) and similar proteins; CBN, the product of the cbn gene, is a Drosophila homolog to vertebrate neuronal six EF-hand calcium binding proteins. It is expressed through most of ontogenesis with a selective distribution in the nervous system and in a few small adult thoracic muscles. Its precise biological role remains unclear. CBN contains six EF-hand motifs, but some of them may not bind calcium ions due to the lack of key residues.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 156101878  13 FKEAFSLFDKDGDGTITTKELGTVMRSL----------GQNPTEAELQDMINE----IDTDGNGTIDFPE---------- 68
Cdd:cd16179    1 FMDVWNHYDTDGNGYIEGTELDGFLREFvssvnpedvgPEVVSETALEELKEEfmeaYDENQDGRIDIRElaqllpteen 80

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 156101878  69 FLTLMARKMKdTDTEEELIEAFRVFDRDGDGYISADELRHVMTNL-----------GEKLtNEEVDEMIREADIDGDGQI 137
Cdd:cd16179   81 FLLLFRRDNP-LDSSVEFMKVWREYDKDNSGYIEADELKNFLKHLlkeakrdndvsEDKL-IEYTDTILQLFDRNKDGKL 158

                        170
                 ....*....|..
gi 156101878 138 NYEEFVKMMIAK 149
Cdd:cd16179  159 QLSEMARLLPVK 170

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 156101878  10 ISEFKEAFSLFDKDGDGTITTKELGTVMRSLGQNPTEAELQDMINEIDTDGNGTIDFPEFLTLMArkMKDTdteeeLIEA 89
Cdd:cd16183   66 ITDWQNCFRSFDRDNSGNIDKNELKQALTSFGYRLSDQFYDILVRKFDRQGRGTIAFDDFIQCCV--VLQT-----LTDS 138

                         90
                 ....*....|..
gi 156101878  90 FRVFDRDGDGYI 101
Cdd:cd16183  139 FRRYDTDQDGWI 150

Penta-EF hand, calcium binding motifs, found in Drosophila melanogaster calpain-A (CalpA), calpain-B (CalpB), and similar proteins; The family contains two calpains that have been found in Drosophila, CalpA and CalpB. CalpA, also termed calcium-activated neutral proteinase A (CANP A), or calpain-A catalytic subunit, is a Drosophila calpain homolog specifically expressed in a few neurons in the central nervous system, in scattered endocrine cells in the midgut, and in blood cells. CalpB, also termed calcium-activated neutral proteinase B (CANP B), contains calpain-B catalytic subunit 1 and calpain-B catalytic subunit 2. Both CalpA and CalpB are closely related to that of vertebrate calpains, and they share similar domain architecture, which consists of four domains: the N-terminal domain I, the catalytic domain II carrying the three active site residues, Cys, His and Asn, the Ca2+-regulated phospholipid-binding domain III, and penta-EF-hand Ca2+-binding domain IV. Besides, CalpA and CalpB display some distinguishing structural features that are not found in mammalian typical calpains. CalpA harbors a 76 amino acid long hydrophobic stretch inserted in domain IV, which may be involved in membrane attachment of this enzyme. CalpB has an unusually long N-terminal tail of 224 amino acids, which belongs to the class of intrinsically unstructured proteins (IUP) and may become ordered upon binding to target protein(s). Moreover, they do not need small regulatory subunits for their catalytic activity, and their proteolytic function is not regulated by an intrinsic inhibitor as the Drosophila genome contains neither regulatory subunit nor calpastatin orthologs. As a result, they may exist as a monomer or perhaps as a homo- or heterodimer together with a second large subunit. Furthermore, both CalpA and CalpB are dispensable for viability and fertility and do not share vital functions during Drosophila development. Phosphatidylinositol 4,5-diphosphate, phosphatidylinositol 4-monophosphate, phosphatidylinositol, and phosphatidic acid can stimulate the activity and the rate of activation of CalpA, but not CalpB. Calpain A modulates Toll responses by limited Cactus/IkappaB proteolysis. CalpB directly interacts with talin, an important component of the focal adhesion complex, and functions as an important modulator in border cell migration within egg chambers, which may act via the digestion of talin. CalpB can be phosphorylated by cAMP-dependent protein kinase (protein kinase A, PKA; EC 2.7.11.11) at Ser240 and Ser845, as well as by mitogen-activated protein kinase (ERK1 and ERK2; EC 2.7.11.24) at Thr747. The activation of the ERK pathway by extracellular signals results in the phosphorylation and activation of calpain B. In Schneider cells (S2), calpain B was mainly in the cytoplasm and upon a rise in Ca2+ the enzyme adhered to intracellular membranes.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 156101878  52 MINEIDTDGNGTIDFPEFLTLMA--RKMKDtdteeelieAFRVFDRDGDGYISADELRHVMTNLGEKLTNEEVDEMI-RE 128
Cdd:cd16196   46 MVAMMDVDRSGKLGFEEFKKLWEdlRSWKR---------VFKLFDTDGSGSFSSFELRNALNSAGFRLSNATLNALVlRY 116

                         90
                 ....*....|....*....
gi 156101878 129 AdiDGDGQINYEEFVKMMI 147
Cdd:cd16196  117 S--NKDGRISFDDFIMCAV 133

EF-hand domain pair;

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 156101878   24 GDGTITTKELGTVMRSLG-QNPTEAELQDMINEIDTDGNGTIDFPEFLTLMAR 75
Cdd:pfam13833   1 EKGVITREELKRALALLGlKDLSEDEVDILFREFDTDGDGYISFDEFCVLLER 53

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 156101878   6 TEEQISEFKEAFSLFDKDGDGTITTKE----LGTVMRSLGQNP-TEAELQDMINEIDTDGNGTIDFPEFLTL 72
Cdd:cd16252   32 SEQQEEAIRKAFQMLDKDKSGFIEWNEikyiLSTVPSSMPVAPlSDEEAEAMIQAADTDGDGRIDFQEFSDM 103

Penta-EF hand, calcium binding motifs, found in calpain-8 (CAPN8); CAPN8, also termed new calpain 2 (nCL-2), or stomach-specific M-type calpain, is a calpain large subunit predominantly expressed in the stomach. It appears to be involved in membrane trafficking in the gastric surface mucus cells (pit cells), via its location at the Golgi and interaction with the beta-subunit of coatomer complex (beta-COP) of vesicles derived from the Golgi. Moreover, CAPN8, together with CAPN9, 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. CAPN8 exists as both a monomer and homo-oligomer, but not as a heterodimer with the conventional calpain regulatory subunit (30K). The monomer and homodimer forms predominate. CAPN8 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 156101878  12 EFKEAFSLFDKDgDGTITTKELGTVM-RSLGQNP-------TEAELQDMINEIDTDGNGTIDFPEFLTLMARKMKdtdte 83
Cdd:cd16191    1 EFKNIFQKLAGK-KCEVTANELQTILnRVLSKRKdiksdgfTINTCREMISLLDTDGTGTLGLVEFRILWMKIQK----- 74

                         90       100       110       120       130       140
                 ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 156101878  84 eeLIEAFRVFDRDGDGYISADELRHVMTNLGEKLtNEEVDEMIREADIDGDGQINYEEFVKMMI 147
Cdd:cd16191   75 --YLAIYKKVDSDRSGTIDAHEMRNALQEAGFTL-NNKIQQSIVQRYASNKLTINFDGFIACMI 135