title: Auto-thiophosphorylation activity of Src tyrosine kinase.
abstract: Intermolecular autophosphorylation at Tyr416 is a conserved mechanism of activation among the members of the Src family of nonreceptor tyrosine kinases. Like several other tyrosine kinases, Src can catalyze the thiophosphorylation of peptide and protein substrates using ATPγS as a thiophosphodonor, although the efficiency of the reaction is low.
  
  
  
  Here, we have characterized the ability of Src to auto-thiophosphorylate. Auto-thiophosphorylation of Src at Tyr416 in the activation loop proceeds efficiently in the presence of Ni(2+), resulting in kinase activation. Other tyrosine kinases (Ack1, Hck, and IGF1 receptor) also auto-thiophosphorylate in the presence of Ni(2+). Tyr416-thiophosphorylated Src is resistant to dephosphorylation by PTP1B phosphatase.
  
  
  
  Src and other tyrosine kinases catalyze auto-thiophosphorylation in the presence of Ni(2+). Thiophosphorylation of Src occurs at Tyr416 in the activation loop, and results in enhanced kinase activity. Tyr416-thiophosphorylated Src could serve as a stable, persistently-activated mimic of Src.
authors.affiliation: Department of Physiology and Biophysics, School of Medicine, Stony Brook University, Stony Brook, NY, 11794, USA.|Biological Sciences Department, SUNY College at Old Westbury, Old Westbury, NY, 11568, USA.
authors.forename: M Zulema
authors.initials: MZ
authors.lastname: Cabail
authors.affiliation: Proteomics Shared Resource at the Herbert Irving Comprehensive Cancer Center, New York, NY, 10032, USA.|Department of Pharmacology, Columbia University Medical Center, New York, NY, 10032, USA.
authors.forename: Emily I
authors.initials: EI
authors.lastname: Chen
authors.affiliation: Proteomics Shared Resource at the Herbert Irving Comprehensive Cancer Center, New York, NY, 10032, USA.
authors.forename: Antonius
authors.initials: A
authors.lastname: Koller
authors.affiliation: Department of Physiology and Biophysics, School of Medicine, Stony Brook University, Stony Brook, NY, 11794, USA. todd.miller@stonybrook.edu.
authors.forename: W Todd
authors.identifier: 0000-0002-6566-0064
authors.initials: WT
authors.lastname: Miller
mesh_terms: D000595:Amino Acid Sequence; D002851:Chromatography, High Pressure Liquid; D009532:Nickel / Q000737:chemistry; D010748:Phosphopeptides / Q000032:analysis; D010766:Phosphorylation; D017434:Protein Structure, Tertiary; D054562:Protein Tyrosine Phosphatase, Non-Receptor Type 1 / Q000378:metabolism; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000302:isolation & purification; D053719:Tandem Mass Spectrometry; D014443:Tyrosine / Q000378:metabolism; D019061:src-Family Kinases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
chemical_list: D010748:Phosphopeptides; D011994:Recombinant Proteins; D014443:Tyrosine; D009532:Nickel; D019061:src-Family Kinases; D054562:Protein Tyrosine Phosphatase, Non-Receptor Type 1
keywords: Autophosphorylation; Phosphatase; Src; Thiophosphate; Tyrosine kinase