Annexins

Title: Annexins
Literature References: Family of calcium and phopholipid binding proteins; virtually ubiquitous in both animal and plant cells. Characterized by a common structure composed of 4 or 8 homologous repeats of ~70 amino acids. Involved in membrane trafficking, transmembrane channel activity, inhibition of phospholipase A2, and inhibition of coagulation. Known variously by such names as synexin, lipocortin, anchorin, and calpactin, the term annexins was chosen for their ability to bind, or "annex", to cellular membranes. Description of nomenclature: M. J. Crumpton, J. R. Dedman, Nature 345, 212 (1990). Isoln of synexin from bovine adrenal medullary tissue: C. E. Creutz et al., J. Biol. Chem. 253, 2858 (1978). Review of discovery, molecular biology and bioactivites: P. Raynal, H. B. Pollard, Biochim. Biophys. Acta 1197, 63-93 (1994); of annexins in plant cells: G. B. Clark, S. J. Roux, Plant Physiol. 109, 1133-1139 (1995). Review of three-dimensional structure: S. Liemann, R. Huber, Cell. Mol. Life Sci. 53, 516-521 (1997). Review of role in plasminogen binding: H.-M. Kang et al., Trends Cardiovasc. Med. 9, 92-102 (1999); K. A. Hajjar, S. Krishman, ibid. 128-138; of role in membrane fusion: H. Kubista et al., Subcell. Biochem. 34, 73-131 (2000); as nucleotide binding proteins: J. Bandorowicz-Pikula et al., BioEssays 23, 170-178 (2001). Comprehensive description: V. Gerke, S. E. Moss, Physiol. Rev. 82, 331-371 (2002).
Annotinine Anot Anserine Antazoline Antheridiol

Annexin
Annexin.png
Structure of human annexin III.
Identifiers
Symbol Annexin
Pfam PF00191
InterPro IPR001464
PROSITE PDOC00195
SCOP 2ran
SUPERFAMILY 2ran
TCDB 1.A.31
OPM superfamily 43
OPM protein 1w3w

Annexin is a common name for a group of cellular proteins. They are mostly found in eukaryotic organisms (animal, plant and fungi).

In humans, the annexins are found inside the cell. However some annexins (Annexin A1, Annexin A2, and Annexin A5) have also been found outside the cellular environment, for example, in blood. How the annexins are transported out of the cell into the blood is a mystery because they lack a signal peptide necessary for proteins to be transported out of the cell.[citation needed]

Annexin is also known as lipocortin.[1] Lipocortins suppress phospholipase A2.[2] Increased expression of the gene coding for annexin-1 is one of the mechanisms by which glucocorticoids (such as cortisol) inhibit inflammation.