title: Allosteric inhibition of the nonMyristoylated c-Abl tyrosine kinase by phosphopeptides derived from Abi1/Hssh3bp1.
abstract: Here we report c-Abl kinase inhibition mediated by a phosphotyrosine located in trans in the c-Abl substrate, Abi1. The mechanism, which is pertinent to the nonmyristoylated c-Abl kinase, involves high affinity concurrent binding of the phosphotyrosine pY213 to the Abl SH2 domain and binding of a proximal PXXP motif to the Abl SH3 domain. Abi1 regulation of c-Abl in vivo appears to play a critical role, as demonstrated by inhibition of pY412 phosphorylation of the nonmyristoylated Abl by coexpression of Abi1. Pervanadate-induced c-Abl kinase activity was also reduced upon expression of the wild type Abi1 but not by expression of the Y213 to F213 mutant Abi1 in LNCaP cells, which are naturally deficient in the regulatory pY213. Our findings suggest a novel mechanism by which Abl kinase is regulated in cells.
authors.affiliation: Laboratory of Cell Signaling, New York Blood Center, New York, NY 10065, USA.
authors.forename: Xiaoling
authors.initials: X
authors.lastname: Xiong
authors.forename: Ping
authors.initials: P
authors.lastname: Cui
authors.forename: Sajjad
authors.initials: S
authors.lastname: Hossain
authors.forename: Rong
authors.initials: R
authors.lastname: Xu
authors.forename: Brian
authors.initials: B
authors.lastname: Warner
authors.forename: Xinhua
authors.initials: X
authors.lastname: Guo
authors.forename: Xiuli
authors.initials: X
authors.lastname: An
authors.forename: Asim K
authors.initials: AK
authors.lastname: Debnath
authors.forename: David
authors.initials: D
authors.lastname: Cowburn
authors.forename: Leszek
authors.initials: L
authors.lastname: Kotula
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000737:chemistry* / Q000378:metabolism; D000494:Allosteric Regulation; D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D002460:Cell Line; D003598:Cytoskeletal Proteins / Q000737:chemistry* / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000494:pharmacology*; D008024:Ligands; D008969:Molecular Sequence Data; D010748:Phosphopeptides / Q000737:chemistry / Q000494:pharmacology*; D016315:Proto-Oncogene Proteins c-abl / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism*; D014443:Tyrosine / Q000378:metabolism; D014638:Vanadates / Q000494:pharmacology; D018909:src Homology Domains
chemical_list: C513733:ABI1 protein, human; D048868:Adaptor Proteins, Signal Transducing; D003598:Cytoskeletal Proteins; D004791:Enzyme Inhibitors; D008024:Ligands; D010748:Phosphopeptides; C076715:pervanadate; D014638:Vanadates; D014443:Tyrosine; D016315:Proto-Oncogene Proteins c-abl