Annexins as nucleotide-binding proteins: facts and speculations.
Annexins are ubiquitous multifunctional Ca2+ and phospholipid-binding proteins whose mechanism of function remains largely unknown. The accumulated in vitro experimental evidence indicates that ATP and GTP are functional ligands for nucleotide-sensitive annexin isoforms. Such nucleotide binding could modulate Ca2+ homeostasis, vesicular transport and/or signal transduction pathways and link them to cellular energy metabolism. Alternatively, since annexins are able to interact with other nucleotide-utilizing proteins, such as various kinases, GTPases and structural proteins, these proteins could influence the guanine nucleotide exchange metabolism and/or control the activity of various G proteins. The nucleotide-binding properties of annexins may affect the development or maintenance of some pathologies and diseases in which changes in physiological concentrations of purine nucleotides or disruption of Ca2+ homeostasis are crucial targets.
Bandorowicz-Pikula
J
J
Department of Cellular Biochemistry, Nencki Institute of Experimental Biology, Warsaw, Poland. bandor@nencki.gov.pl
Buchet
R
R
Pikula
S
S
D017766:Acid Anhydride Hydrolases / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism*; D000818:Animals; D017302:Annexins / Q000378:metabolism / Q000502:physiology*; D019204:GTP-Binding Proteins / Q000378:metabolism; D006160:Guanosine Triphosphate / Q000378:metabolism*; D006801:Humans; D043583:Nucleoside-Triphosphatase
D017302:Annexins; D006160:Guanosine Triphosphate; D000255:Adenosine Triphosphate; D017766:Acid Anhydride Hydrolases; D019204:GTP-Binding Proteins; D043583:Nucleoside-Triphosphatase