Actin amino acid sequence

Tollman, R.L., Morton, D.J., Clarke, F.M. (1989). A common theme in the amino acid sequences of actin and many actin-binding proteins. Trends Biochem. Sci. 14, 130-133. 

With respect to a solvent, the overall solvation capability for solutes. 2. A property of bodies or systems that have a distinct direction i.e., that have different or opposing physical properties or characteristics at different points. For example, an amino acid sequence in a polypeptide has polarity in that there is an amino end and a carboxyl end of the sequence. Similarly, microtubules and actin filaments have plus (+)-ends and minus (-)-ends that establish directionality for cellular and intracellular locomotion. 3. The state in which there is either a positive or negative aspect relative to the two poles of a magnet or to electrification. 4. Attraction toward an object or attraction in a specific direction. 5. In mathematics, the positive or negative sign of numbers. 

Vandekerckhove J, Weber K (1978) At least six different actins are expressed in a higher mammal An analysis based on the amino acid sequence of the amino-terminal tryptic peptide. In J. Mol. Biol. 126 783-802 Vandekerckhove J, Weber K (1979) The complete amino acid sequence of actins from bovine aorta, bovine heart, bovine fast skeletal muscle and rabbit slow skeletal muscle. In Differentiation 14 123-33 Wegner A, Aktories K (1988) ADP-ribosylated actin caps the barbed ends of actin filaments. In J. Biol. Chem. 263 13739-42... 

The discussion above stresses the importance of the CN4 region (residues 96-116) of troponin I in the inhibition of contractile interaction of myosin-actin in the presence of tropomyosin. The amino acid sequence of the CN4 region is shown in Fig. 3. Talbot and Hodges (1981) synthesized 12 peptide analogs of the CN4 sequence and examined their inhibitory action on actomyosin ATPase activity. The absence of residues 115 and 116 did not affect the activity, whereas the absence of residue 114 significantly decreased the inhibitory action. As to the N-terminal portion of the peptide, residues 96-103 were not essential, but the absence of Lys-105 decreased the inhibitory activity. A peptide containing the region of residues Lys-105-Val-l 14 showed about half of the inhibitory action of troponin I. The authors concluded that Lys-105 and the bulky side chain at Val-114 are essential for the inhibitory action of troponin I (Fig. 3). 

The structure mentioned above is by no means a unique solution for the structure of tropomyosin and troponin. But it is certain that these studies are useful in integrating the enormous amount of experimental evidence, and in visualizing how Ca " changes the troponin complex at the level of the amino acid sequence. Information on the interacting regions of the actin molecule for tropomyosin and troponin I will surely lead to another breakthrough for this line of approaches. 

Considering the ubiquitous distribution of actin and its highly conserved amino acid sequence, it is not surprising that actin is a poor antigen, regardless of its source. Cavadore et al. (1987), however, were able... 

Actin is a highly conserved protein, and actin variants display approximately 95% amino acid sequence homology (Pollard and Cooper, 1986). In vertebrate tissues, six different actin isoforms have been identified on the basis of electrophoretic mobility and sequence data, and each is encoded by a distinct gene (Vandekerckhove and Weber, 1978 Reddy et al., 1990). a, p, and 7 species can be easily separated by isoelectric focusing the a-isoform is the most acidic and the 7-isoform the least (Vandekerckhove and Weber, 1979a). These variants can be further subdivided on the basis of their amino acid sequence and include three a-isoforms (a-skeletal, a-cardiac, and a-vascular), two 7-isoforms (7-enteric and 7-cytoplasmic), and one p-isoform (p-cytoplasmic). 

Protein ( histidine ) Methyltransferase. An enzyme which methylates histidine in proteins to give primarily 3-methylhistidine residues has been observed in myofibrillar protein and in the sarcoplasmic fraction of muscle homogenates (218). S-Adenosyl-L-methionine serves as the methyl donor for the enzyme. The enzyme has not been solubilized and purified. Very little is known about the substrate specificity of protein-(histidine) methyltransferase. Actins from a wide variety of species consistently contain one 3-N-methylhistidine residue per molecule (191, 219). It appears that myosin from white muscle contains two residues of 3-N-methylhistidine (one residue per heavy chain), whereas myosin from red muscle contains no 3-N-methylhistidine (220). The amino acid sequence around the methylated residue of rabbit skeletal muscle is (221) ... 

At least six different isoforms of actin hav been identified in vertebrate tissues, each encoded by a different gene (Vanderkerckhove and Weber 1978, Reddy et al 1990). Four of these isoforms have been identified in the smooth muscle tissues of warm-blooded vertebrates a and y smooth muscle actin, and p and y non-muscle actin (Kabsch and Vanderkerckhove 1992). These actin variants have approximately 95% amino acid sequence homology, and differ primarily in their N-terminal sequence (Pollard and Cooper 1986). 

Vandekerckhove J, Weber K (1978) At least six different actins are expressed in a higher mammal an analysis based on the amino acid sequence of the amino-terminal tryptic peptide. J Mol Biol 126 783-802... 

Smooth muscle-type actin isoforms Six isoforms of actin are expressed in mammalian SM tissues that are generated by distinct genes [79] and show an highly conserved amino acid sequences across species. The expression of actin isoforms is developmen-tally regulated in a temporal-spatial manner [80-83]. Fully differentiated SMC contain a- (mainly in vascular tissue) and y-(mainly in the enteric structures) actins and trace amounts of (3- and y-cytoplasmic actin isoforms [79,84-87]. The SM a-isoform is expressed also in striated muscle [88], and the SM y-isoform in post-meiotic sperm [89], and the increased SM y-actin content in hypertrophied bladder SM [86,90]. The unique intracellular distribution of actin filamentous networks [91-93] and the decreased SM a-actin content in proliferating vascular SMC ([94] see Section 6) point to an isoform diversification based on specific functional requirements. 

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