Open AccessAnnexin VI: an intracellular target for ATP.
Author(s) -
Joanna BandorowiczPikuła,
Małgorzata Danieluk,
Antoni Wrzosek,
Renata Buś,
René Buchet,
Sławomir Pikuła
Publication year - 1999
Publication title -
acta biochimica polonica
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.452
H-Index - 78
eISSN - 1734-154X
pISSN - 0001-527X
DOI - 10.18388/abp.1999_4152
Subject(s) - annexin , biochemistry , nucleotide , microbiology and biotechnology , chemistry , calcium binding protein , gtp' , binding domain , binding site , biology , biophysics , calcium , in vitro , enzyme , organic chemistry , gene
Annexin VI (AnxVI), an Ca2+- and phospholipid-binding protein, interacts in vitro with ATP in a calcium-dependent manner. Experimental evidence indicates that its nucleotide-binding domain which is localized in the C-terminal half of the protein differs structurally from ATP/GTP-binding motifs found in other nucleotide-binding proteins. The amino-acid residues of AnxVI directly involved in ATP binding have not been yet defined. Binding of ATP to AnxVI induces changes in the secondary and tertiary structures of protein, affecting the affinity of AnxVI for Ca2+ and, in consequence, influencing the Ca2+-dependent activities of AnxVI: binding to F-actin and to membranous phospholipids, and self-association of the annexin molecules. These observations suggest that ATP is a functional ligand for AnxVI in vivo, and ATP-sensitive AnxVI may play the role of a factor coupling vesicular transport and calcium homeostasis to cellular metabolism.