Amino actin

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. 

The smdy of tissue protein breakdown in vivo is difficult, because amino acids released during intracellular breakdown of proteins can be extensively reutilized for protein synthesis within the cell, or the amino acids may be transported to other organs where they enter anabohc pathways. However, actin and myosin are methylated by a posttranslational reaction, forming d-methylliistidine. During intracellular breakdown of actin and myosin, 3-methylhistidine is released and excreted into the urine. The urinary output of the methylated amino acid provides a rehable index of the rate of myofibrillar protein breakdown in the musculature of human subjects. 

The fifth was a molecular biologist, who smiled sweetly and pointed out that all the others had missed the point. The frog jumps because of the biochemical properties of its muscles. The muscles are largely composed of two interdigitated filamentous proteins, actin and myosin, and they contract because the protein filaments slide past each other. This property of the actin and myosin is dependent on the amino acid composition of the two proteins, and hence on chemical, and thus on physical properties. In the last analysis, the molecular biologist insisted, following James Watson, we are all nothing but subatomic particles. 

Figure 10.7 The EGF receptor. The N-terminal, extracellular region of the receptor contains 622 amino acids. It displays two cysteine-rich regions, between which the ligand-binding domain is located. A 23 amino acid hydrophobic domain spans the plasma membrane. The receptor cytoplasmic region contains some 542 amino acids. It displays a tyrosine kinase domain, which includes several tyrosine autophosphorylation sites, and an actin-binding domain that may facilitate interaction with the cell cytoskeleton...

Modified amino acids, which occur in special proteins such as hydroxyproline in collagen and 3-methylhistidine in actin and myosin, can be used as indicators of the degradation of these proteins. 

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. 

ACTIN ASSEMBLY KINETICS MICROTUBULE ASSEMBLY KINETICS Triglyceride synthesis kinetics (hepatic), LIRID TRACER KINETICS 2,4,5-Trihydroxyphenylalanine quinone, REDOX-ACTIVE AMINO ACIDS TRIMOLECULAR MOLECUARITY ORDER... 

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