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

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 300192904 137 KLRWTFNLYDINKDGYINKEEMMDIVKAIYdmmgkytypvlkEDTPRQHVDVFFQKMDKNKDGIVTLDEFLE 208
Cdd:cd00051    1 ELREAFRLFDKDGDGTISADELKAALKSLG------------EGLSEEEIDEMIREVDKDGDGKIDFEEFLE 60

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 300192904   137 KLRWTFNLYDINKDGYINKEEMMDIVKAI 165
Cdd:smart00054   1 ELKEAFRLFDKDGDGKIDFEEFKDLLKAL 29

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

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 300192904 137 KLRWTFNLYDINKDGYINKEEMMDIVKAIYdmmgkytypvlkEDTPRQHVDVFFQKMDKNKDGIVTLDEFLE 208
Cdd:cd00051    1 ELREAFRLFDKDGDGTISADELKAALKSLG------------EGLSEEEIDEMIREVDKDGDGKIDFEEFLE 60

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 300192904 101 YAHYLFNAFDTTQTGSVKFEDFVTALSILLRGTVHEKLRWTFNLYDINKDGYINKEEMMDIVK 163
Cdd:cd00051    1 ELREAFRLFDKDGDGTISADELKAALKSLGEGLSEEEIDEMIREVDKDGDGKIDFEEFLELMA 63

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

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 300192904 136 EKLRWTFNLYDINKDGYINKEEMMDIVKAIYDMM---------GKYT-------YPVLKEDTPRQHVDVFFQKMDKNKDG 199
Cdd:COG5126    5 RKLDRRFDLLDADGDGVLERDDFEALFRRLWATLfseadtdgdGRISreefvagMESLFEATVEPFARAAFDLLDTDGDG 84

                 ....*..
gi 300192904 200 IVTLDEF 206
Cdd:COG5126   85 KISADEF 91

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

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 300192904  77 SGVVNEETFKQIYAQFFPHGDASTyAHYLFNAFDTTQTGSVKFEDFVTALSILlrGTVHEKLRWTFNLYDINKDGYINKE 156
Cdd:COG5126   47 DGRISREEFVAGMESLFEATVEPF-ARAAFDLLDTDGDGKISADEFRRLLTAL--GVSEEEADELFARLDTDGDGKISFE 123

                         90
                 ....*....|
gi 300192904 157 EMMDIVKAIY 166
Cdd:COG5126  124 EFVAAVRDYY 133

EF-hand-like motif found in the dystrophin/dystrobrevin/dystrotelin family; The dystrophin/dystrobrevin/dystrotelin family has been characterized by a compact cluster of domains comprising four EF-hand-like motifs and a ZZ-domain, followed by a looser region with two coiled-coils. Dystrophin is the founder member of this family. It is a sub-membrane cytoskeletal protein associated with the inner surface membrane. Dystrophin and its close paralog utrophin have a large N-terminal extension of actin-binding CH domains, up to 24 spectrin repeats, and a WW domain. Its further paralog, dystrophin-related protein 2 (DRP-2), retains only two of the spectrin repeats. Dystrophin, utrophin or DRP2 can form the core of a membrane-bound complex consisting of dystroglycan, sarcoglycans and syntrophins, known as the dystrophin-glycoprotein complex (DGC) that plays an important role in brain development and disease, as well as in the prevention of muscle damage. Dystrobrevins, including alpha- and beta-dystrobrevin, lack the large N-terminal extension found in dystrophin, but alpha-dystrobrevin has a characteristic C-terminal extension. Dystrobrevins are part of the DGC. They physically associate with members of the dystrophin family and with the syntrophins through their homologous C-terminal coiled coil motifs. In contrast, dystrotelins lack both the large N-terminal extension found in dystrophin and the obvious syntrophin-binding sites (SBSs). Dystrotelins are not critical for mammalian development. They may be involved in other forms of cytokinesis. Moreover, dystrotelin is unable to heterodimerize with members of the dystrophin or dystrobrevin families, or to homodimerize.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 300192904 105 LFNAFDTTQTGSVKFEDFVTALSILLRGTVHEKLRWTFNLYDiNKDGYINKE-------EMMDIVKAIY 166
Cdd:cd15901   59 LLNLYDRNRTGCIRLLSVKIALITLCAASLLDKYRYLFGQLA-DSSGFISRErltqflqDLLQIPDLIG 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
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 300192904 142 FNLYDINKDGYINKEEMMdivkaiydmmgKYTYPvlkEDTPRQH---VDVFFQKMDKNKDGIVTLDEFL 207
Cdd:cd16227  128 FEAADLNKDGKLDKTEFS-----------AFQHP---EEYPHMHpvlIEQTLRDKDKDNDGFISFQEFL 182

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 300192904 101 YAHYLFNAFDTTQTGSVKFEDFVTALSILlrgTVHEKLRWTFNLYDINKDGYINKEEMMDIVKAiydmmgkytypVLKED 180
Cdd:cd15898   37 ELKKLFKEVDTNGDGTLTFDEFEELYKSL---TERPELEPIFKKYAGTNRDYMTLEEFIRFLRE-----------EQGEN 102

                         90       100
                 ....*....|....*....|....*...
gi 300192904 181 TPRQHVDVFFQKMDKN-KDGIVTLDEFL 207
Cdd:cd15898  103 VSEEECEELIEKYEPErENRQLSFEGFT 130

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
                 ....*....|....*....|....*....|....*....|....*....|....*....|
gi 300192904 105 LFNAFDTTQTGSVKFEDFVTALSILLRgtvhekLRWTFNLYDINKDGY--INKEEMMDIV 162
Cdd:cd16180  108 LVRKFDRRRRGSISFDDFVEACVTLKR------LTDAFRKYDTNRTGYatISYEDFLTMV 161

EF-hand, calcium binding motif, found in calumenin, reticulocalbin-1 (RCN-1), reticulocalbin-3 (RCN-3), and similar proteins; The family corresponds to a group of six EF-hand Ca2+-binding proteins, including calumenin (also known as crocalbin or CBP-50), reticulocalbin-1 (RCN-1), reticulocalbin-3 (RCN-3), and similar proteins. Calumenin is an endo/sarcoplasmic reticulum (ER/SR) resident low-affinity Ca2+-binding protein that contains six EF-hand domains and a C-terminal SR retention signal His-Asp-Glu-Phe (HDEF) tetrapeptide. It functions as a novel regulator of SERCA2, and its expressional changes are tightly coupled with Ca2+-cycling of cardiomyocytes. It is also broadly involved in haemostasis and in the pathophysiology of thrombosis. Moreover, the extracellular calumenin acts as a suppressor of cell migration and tumor metastasis. RCN-1 is an endoplasmic reticulum resident Ca2+-binding protein with a carboxyl-terminal His-Asp-Glu-Leu (HDEL) tetrapeptide signal. It acts as a potential negative regulator of B-RAF activation and can negatively modulate cardiomyocyte hypertrophy by inhibition of the mitogen-activated protein kinase signalling cascade. It also plays a key role in the development of doxorubicin-associated resistance. RCN-3 is a putative six EF-hand Ca2+-binding protein that contains five RXXR (X is any amino acid) motifs and a C-terminal ER retrieval signal HDEL tetrapeptide. The RXXR motif represents the target sequence of subtilisin-like proprotein convertases (SPCs). RCN-3 is specifically bound to the paired basic amino-acid-cleaving enzyme-4 (PACE4) precursor protein and plays an important role in the biosynthesis of PACE4.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 300192904 135 HEKLRWtfNLYDINKDGYINKEEMMDIVkaiydmmgkytYPvlkEDTPRQH---VDVFFQKMDKNKDGIVTLDEFL 207
Cdd:cd16226  120 RDERRW--KAADQDGDGKLTKEEFTAFL-----------HP---EEFPHMRdivVQETLEDIDKNKDGFISLEEYI 179

EF-hand domain pair;

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*....
gi 300192904  113 QTGSVKFEDFVTALSILLRGTVHE-KLRWTFNLYDINKDGYINKEEMMD 160
Cdd:pfam13833   1 EKGVITREELKRALALLGLKDLSEdEVDILFREFDTDGDGYISFDEFCV 49