Signal transduction mechanisms in the regulation of protein synthesis.
Control of polypeptide synthesis plays an important role in cell proliferation and translation rates generally reflect the growth state of the cultured eukaryotic cell. Physiological regulation of protein synthesis is almost always exerted at the level of polypeptide chain initiation, with the binding of mRNA to the small ribosomal subunit a rate-limiting step in many cell systems. Studies have indicated key roles in the regulation of protein synthesis for the structural features of mRNA molecules and phosphorylation of initiation factors which catalyse this process. This review focuses on translational regulation at the level of mRNA binding to the ribosome and the role of phosphorylation of initiation factors in mediating both quantitative and qualitative control. The identity of putative kinases which may mediate these processes is addressed and a possible model for the role of a transient activation of initiation factors in cell growth or differentiation is presented.
Department of Biochemistry, School of Biological Sciences, University of Sussex, Falmer, Brighton, UK.
S J
SJ
Morley
D000818:Animals; D005057:Eukaryotic Cells / Q000378:metabolism; D006801:Humans; D010442:Peptide Chain Initiation, Translational; D010448:Peptide Initiation Factors / Q000378:metabolism; D010766:Phosphorylation; D014176:Protein Biosynthesis; D039381:RNA Cap-Binding Proteins; D012333:RNA, Messenger / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000378:metabolism; D012270:Ribosomes / Q000378:metabolism; D015398:Signal Transduction
D010448:Peptide Initiation Factors; D039381:RNA Cap-Binding Proteins; D012333:RNA, Messenger; D016601:RNA-Binding Proteins