title: PEST sequences in calmodulin-binding proteins.
abstract: Many short-lived proteins which are devoid of proteolytic activity contain PEST sequences which are segments along the polypeptide chain that are rich in proline (P), glutamate (E), serine (S) and threonine (T). These designated PEST sequences are believed to be putative intramolecular signals for rapid proteolytic degradation. Calmodulin is a ubiquitous, 17 kDa, acidic Ca(2+)-binding protein which plays an important role in the regulation of many physiological processes through its interaction with a wide range of calmodulin-binding proteins. Several calmodulin-binding proteins are known to contain PEST sequences and are susceptible to proteolysis by endogenous neutral proteases such as calpain I and calpain II. In this report, we discuss the functions of PEST sequences in calmodulin-binding proteins and assess the correlation between calmodulin-binding proteins and PEST sequences.
authors.affiliation: Department of Biochemistry, Faculty of Medical Sciences, University of The West Indies, St. Augustine, Trinidad and Tobago, West Indies.
authors.forename: J A
authors.initials: JA
authors.lastname: Barnes
authors.forename: A V
authors.initials: AV
authors.lastname: Gomes
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000737:chemistry*; D000252:Calcium-Transporting ATPases / Q000737:chemistry; D002147:Calmodulin / Q000737:chemistry*; D002148:Calmodulin-Binding Proteins / Q000737:chemistry*; D002154:Calpain / Q000502:physiology*; D016384:Consensus Sequence; D006801:Humans; D008969:Molecular Sequence Data; D015398:Signal Transduction; D014452:Ubiquitins / Q000502:physiology
chemical_list: D002147:Calmodulin; D002148:Calmodulin-Binding Proteins; D014452:Ubiquitins; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D002154:Calpain; D000252:Calcium-Transporting ATPases