Protein stability regulator

VHL protein stability regulator renal (clear cell), von Hippel Lindau syndrome... 

GPCR function has been shown to be regulated by several different mechanisms. The number of receptors on the plasma membrane may be regulated by transcription, mRNA stability, biosynthetic processing, and protein stability. In addition, the function of receptors in the plasma membrane can be influenced by regulatory phosphorylation and by association with other proteins that determine the subcellular location of receptors relative to other signaling molecules. 

VHL Regulator of protein stability Renal cell cancer... 

Chen G, Manji HK. Mood stabilizers regulate cytoprotective and mRNA binding proteins in the brain Long term effects on cell survival and transcript stability. Int J Neuropsychopharmacol 2001 4 47-64. 

Zinc, in addition to its use as a Lewis acid in enzyme catalysis, plays a structural role in stabilizing protein molecules. It is also involved in a characteristic motif, termed zinc finger, in a number of eukaryotic DNA-binding proteins (that regulate the transcription of DNA into RNA), first described by Aaron Klug. 

DE Geaae, P., et al., Hdmx protein stability is regulated by the ubiquitin ligase activity of Mdm2. J Biol Chem, 2003, 278(40), 38315-24. 

Another level of control is mediated through the control of F-box protein stabilities by the SCF complex using an auto-ubiquitination mechanism. Deletion of the F-box motif of various F-box proteins such as yeast Cdc4 or j5-Trcp abolishes the interaction between Skpl/Cull and the F-box proteins [66]. Consequently the F-box proteins become more stable. This regulation may provide a means to recycle the components of SCF complexes between different F-box proteins. In addition, the levels of a particular F-box protein may be in part regulated by the balance between autoubiquitination and substrate-specific ubiquitination and thus could be sensitive to the presence of the substrates. 

W. P. Skp2 regulates Myc protein stability and activity. Mol Gell 2003, 3 3, 1177-88. 

The complexity of regulation of Raf kinase was shown by the discovery of a further three proteins which can specifically associate with Raf kinase (review Morrison and Cutler, 1997, Sternberg and Alberola-Ila, 1998). Members of the family of 14-3-3 proteins are found associated with Raf kinase. The 14-3-3 proteins recognize and bind phosphoserine residues in a particular sequence environment. It is assumed that the 14-3-3 proteins bind to Ser-phosphate residues of Raf kinase and thereby fix it in an inactive conformation. Other Raf-interacting proteins include the molecular chaperones hsp90 and p50. These proteins appear to be important for maintaining protein stability and for the proper localization of Raf kinase within the cell. 

Effect of mRNA and Protein Stability on Regulation E. coli cells are growing in a medium with glucose as the sole carbon source. Tryptophan is suddenly added. The cells continue to grow, and divide every 30 min. Describe (qualitatively) how the amount of tryptophan synthase activity in the cells changes with time under the following conditions ... 

CYP2E1 is the only member of the CYP2E family in most mammals with the exception of rabbits. Substrates for this family tend to be of small molecular weight and include ethanol, carbon tetrachloride, benzene, and acetaminophen. In contrast to many other inducible CYP families, CYP2E1 is regulated by a combination of increased transcription levels and increased message and protein stabilization. 

Vazquez, F., Ramaswamy, S., Nakamura, N., and Sellers, W. R. (2000). Phosphorylation of the PTEN tail regulates protein stability and function. Mol. Cell. Biol. 20, 5010-5018. 

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