A Combined Approach Reveals a Regulatory Mechanism Coupling Src's Kinase Activity, Localization, and Phosphotransferase-Independent Functions.
Multiple layers of regulation modulate the activity and localization of protein kinases. However, many details of kinase regulation remain incompletely understood. Here, we apply saturation mutagenesis and a chemical genetic method for allosterically modulating kinase global conformation to Src kinase, providing insight into known regulatory mechanisms and revealing a previously undiscovered interaction between Src's SH4 and catalytic domains. Abrogation of this interaction increased phosphotransferase activity, promoted membrane association, and provoked phosphotransferase-independent alterations in cell morphology. Thus, Src's SH4 domain serves as an intramolecular regulator coupling catalytic activity, global conformation, and localization, as well as mediating a phosphotransferase-independent function. Sequence conservation suggests that the SH4 domain regulatory interaction exists in other Src-family kinases. Our combined approach's ability to reveal a regulatory mechanism in one of the best-studied kinases suggests that it could be applied broadly to provide insight into kinase structure, regulation, and function.
['Ahler|Ethan|E|', 'Register|Ames C|AC|', 'Chakraborty|Sujata|S|', 'Fang|Linglan|L|', 'Dieter|Emily M|EM|', 'Sitko|Katherine A|KA|', 'Vidadala|Rama Subba Rao|RSR|', 'Trevillian|Bridget M|BM|', 'Golkowski|Martin|M|', 'Gelman|Hannah|H|', 'Stephany|Jason J|JJ|', 'Rubin|Alan F|AF|', 'Merritt|Ethan A|EA|', 'Fowler|Douglas M|DM|', 'Maly|Dustin J|DJ|']
D000494:Allosteric Regulation D020134:Catalytic Domain D002462:Cell Membrane D057809:HEK293 Cells D006801:Humans D016296:Mutagenesis D010766:Phosphorylation D011487:Protein Conformation D019061:src-Family Kinases
Src kinase activity regulation allostery