Motif EF hand

TPR) domains. PP2B (calcineurin) is a heterodimer of a catalytic A-subunit together with a regulatory, Ca2+-binding B-subunit. The A-subunit additionally carries a calmodulin binding site and an autoinhibitory domain. PP7 also contains EF-hand motifs. Both, PP2B and PP7 are stimulated by Ca2+-ions. 

Most of the EF-hand motifs have one water (—X). On the other hand, in Rhizopus chinensis aspartic proteinase (Suguna et al., 1987) there is one main-chain carbonyl oxygen bound to calcium and six water molecules to complete the pentagonal bipyramidal coordination. Calcium coordination has been measured in several viruses, such as Southern bean mosaic virus (Silva and Rossmann, 1985), satellite tobacco necrosis virus (Jones and Liljas, 1984), and tomato bushy stunt virus IV (Olson et al., 1983). 

Helix-loop-helix (HLH) or EF-hand" motif in -binding sites. The Ca " ligands are part of a 12-residue loop flanked by orthogonal a helices. 

E (entgegen) configuration 43 E3 binding protein 796 Eadie-Hofctee plot 460 E-cadhedrin 574 Echinodermata 25 Ectoderm 23 Ectoenzymes 409 Ectopic proteins 573 Edelman, Gerald M. 84 Edman degradation 118 EDTA. See Ethylenediaminetetraacetic acid Effector(s) of allosteric enzymes 473-475 EF-hand motif 313, 317 EGF (epithelial growth factor), definition of 577... 

Fig. 1. Structure of spectrin superfamily proteins. Modular domains within each protein are clearly defined. Shaded spectrin repeats represent coiled coils involved in dimerization events incomplete repeats represent proportionally the number of coiled-coil helices contributed by a- and /3-spectrin when generating a complete spectrin repeat during formation of the spectrin tetramer. The dashed lines indicate how two spectrin heterodimers interact to form a functional spectrin tetramer. Asterisks in the dystrophin spectrin repeats represent the position of the two greater repeats in dystrophin with respect to utrophin, which in all other respects has a similar overall structure. Numbers in the EF hand regions represent the number of EF hand motifs.

The C-termini of spectrin family proteins also exhibit a variety of structural similarities including motifs involved in protein-protein interactions (Fig. 1). EF-hands motifs are found in all but /3-spectrin. The... 

Domain IV is the C-terminal portion of the protein, and is also known as the calmodulin-like domain due to its similarity with calmodulin. It contains five EF-hand Ca2+-binding motifs, the fifth of which does not bind calcium but is involved in the dimerization with the small subunit, through the interaction with the analogous EF-hand motif in domain VI. The small subunit is composed of two domains (V and VI) separated by a region containing a proline-rich stretch. 

Domain VI is homologous to domain IV of the large subunit, and therefore has five EF-hands motifs, four of which bind calcium while the fifth is involved in the interaction with the large subunit. The crystal structures of domain IV (Blanchard... 

Figure 7. Sequence alignment and positions of mutations associated with disease. Functional EF-hand motifs are shaded. Positions of mutations are indicated by vertical arrows. Conserved residues are printed white on black or gray background. In GCAP1, Y99C is located adjacent to EF3 and I143NT, E155G, L151F are located in EF4. For GCAP2, G157R is located in EF4...

THE BIOCHEMICAL PHENOTYPE OF CONE DYSTROPHIES ASSOCIATED WITH EF-HAND MOTIF MUTATIONS... 

GCAPs belong to the EF-hand motif-containing superfamily of Ca2+-binding proteins from the calmodulin superfamily (Lewit-Bentley and Rety, 2000 Bhattacharya et al., 2004). The structures of several members of the recoverin branch of the EF-hand... 

Vallely et al., 2002 Ikura and Ames, 2006). The C-terminal EF-hand contains the classical Ca2+-binding motif, common to all EF-hand proteins (see above). This Ca2+-binding motif has a typical sequence signature of 12 amino acids and is flanked by helices Hin and HIV. The N-terminal EF-hand is different from the classical EF-hand motif and is characteristic of the S100 proteins. Therefore, this EF-hand, with a 14 amino acid consensus sequence motif, is flanked by helices H, and Hn and is called the SlOO-specific or pseudo EF-hand. 

Lipari, F., and Herscovics, A. (1999). Calcium binding to the class I alpha-1,2-mannosidase from Saccharomyces cerevisiae occurs outside the EF hand motif. 

The calcium binding proteins calbindin D28k, calretinin and parvalbumin are members of a family of proteins characterized by the presence of calcium binding EF-hand motifs, modulated by stimulus-induced increases in cytosolic free calcium ions (Persechini et ah,... 

Figure 4. Linear representation of the Arabidopsis PIPKs and PLCs. The Arabidopsis PtdlnsP 5-kinases are most similar to the human type I PtdlnsP 5-kinases. There are 11 putative type I /I/PtdlnsP 5-kinases in Arabidopsis arranged in two subfamilies based on size. Subfamily B contains X/PIPK1-9, all of which contain membrane occupation and recognition nexus (MORN) repeats. /1/PIPK10-11 are in Subfamily A with molecular weights less than that of the members of subfamily B and contain no MORN repeats. The Arabidopsis phosphoinositide specific phospholipase C family is most similar to the animal PLC . There are seven functional PI-PLCs in Arabidopisis (Hunt et al., 2004). All isoforms contain EF-hand motifs, the X and Y catalytic domains characteristic of PI-PLCs and a C2 lipid-binding domain.

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