«Systems Biology and Physiology Reports:Issue #6»

Published on June 30, 2022

Annexin V: the membrane-binding protein with diverse functions

Annexin V is an eukaryotic protein from the annexin family which is able to reversibly bind to phospholipid membranes in a Ca2+-dependent manner. It possesses a complex mechanism of the membrane binding which includes the two-dimensional lattice formation from annexin V trimers and significant variation of the membrane structure. The precise functions of annexin V are largely unknown, however, its participation in the blood coagulation, membrane repair process and the Ca2+ channel activity is suggested. The usage of annexin V as a marker of phosphatidylserine-positive cells in in vitro and in vivo studies makes the understanding of the protein role in cellular processes critically important.

The current review is focused on the structure of annexin V and the mechanism and kinetics of its membrane binding. The lipid specificity and the multimerization process will be described. Finally, some of the proposed annexin V functions including inhibition of the blood coagulation and the Ca2+ transport activity will be discussed.

The annexin V structure. A. The view from the convex side. Magenta, N-terminal tail; blue, domain I; yellow, domain II; green, domain III; red, domain IV; orange, Ca2+ ions. In the center of annexin V the charged residues Asp280, Arg276, Asp92, Arg117, Glu112, Arg271 are represented. B. The view from the domain II. The convex and the concave sides are marked by black arrows. Ca2+-binding sites are located on the convex surface, N-terminal tail is on the concave side. Figures were created in VMD for the current review using the structure 1ANX [29] from PDB Data Bank. C. Annexin V from human (ANXA5_HUMAN) and from rat (ANXA5_RAT) sequences alignment. Residues that form the Ca2+-binding sites are highlighted in green and yellow for human and rat annexin V respectively. The alignment was done using the UniProt Align tool.
1 382
#annexin A5#membrane interactions#calcium channel#inhibition of coagulation

Approaches to visualize microtubule dynamics in vitro

1 116
#microtubules#light microscopy#atomic force microscopy#dynamic instability#tubulin#associated proteins