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- *********************
- * Actins signatures *
- *********************
-
- Actins [1,2.3] are highly conserved contractile proteins that are present in
- all eukaryotic cells. In vertebrates there are three groups of actin isoforms:
- alpha, beta and gamma. The alpha actins are found in muscle tissues and are a
- major constituent of the contractile apparatus. The beta and gamma actins co-
- exists in most cell types as components of the cytoskeleton and as mediators
- of internal cell motility. In plants [4] there are many isoforms which are
- probably involved in a variety of functions such as cytoplasmic streaming,
- cell shape determination, tip growth, graviperception, cell wall deposition,
- etc.
-
- Actin exists either in a monomeric form (G-actin) or in a polymerized form (F-
- actin). Each actin monomer can bind a molecule of ATP; when polymerization
- occurs, the ATP is hydrolyzed.
-
- Actin is a protein of from 374 to 379 amino acid residues. The structure of
- actin has been highly conserved in the course of evolution.
-
- As signature patterns we selected two conserved region, the first one spans
- positions 54 to 64 of actin and the second one positions 357 to 365.
-
- -Consensus pattern: [FY]-[LIV]-G-[DE]-E-A-Q-x-[RKQ](2)-G
- -Sequences known to belong to this class detected by the pattern: ALL, except
- for five actins.
- -Other sequence(s) detected in SWISS-PROT: NONE.
-
- -Consensus pattern: W-[IV]-[STA]-[RK]-x-[DE]-Y-[DE](2)
- -Sequences known to belong to this class detected by the pattern: ALL, except
- for four actins.
- -Other sequence(s) detected in SWISS-PROT: NONE.
-
- -Last update: May 1991 / Text revised.
-
- [ 1] Pollard T.D., Cooper J.A.
- Annu. Rev. Biochem. 55:987-1036(1986).
- [ 2] Pollard T.D.
- Curr. Opin. Cell Biol. 1:33-40(1990).
- [ 3] Rubenstein P.A.
- BioEssays 12:309-315(1990).
- [ 4] Meagher R.B., McLean B.G.
- Cell Motil. Cytoskeleton 16:164-166(1990).
-