Publication Date:
1991-07-26
Description:
Protein tyrosine phosphatases (PTPs) represent a diverse family of enzymes that exist as integral membrane and nonreceptor forms. The PTPs, with specific activities in vitro 10 to 1000 times greater than those of the protein tyrosine kinases would be expected to effectively control the amount of phosphotyrosine in the cell. They dephosphorylate tyrosyl residues in vivo and take part in signal transduction and cell cycle regulation. Most of the transmembrane forms, such as the leukocyte common antigen (CD45), contain two conserved intracellular catalytic domains; but their external segments are highly variable. The structural features of the transmembrane forms suggest that these receptor-linked PTPs are capable of transducing external signals; however, the ligands remain unidentified. A hypothesis is proposed explaining how phosphatases might act synergistically with the kinases to elicit a full physiological response, without regard to the state of phosphorylation of the target proteins.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Fischer, E H -- Charbonneau, H -- Tonks, N K -- DK07902/DK/NIDDK NIH HHS/ -- GM15731/GM/NIGMS NIH HHS/ -- GM42508/GM/NIGMS NIH HHS/ -- New York, N.Y. -- Science. 1991 Jul 26;253(5018):401-6.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Biochemistry, University of Washington, Seattle 98195.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/1650499" target="_blank"〉PubMed〈/a〉
Keywords:
Amino Acid Sequence
;
Animals
;
Cell Cycle
;
Genetic Variation
;
Humans
;
Isoenzymes/*genetics/metabolism
;
Membrane Proteins/genetics/metabolism
;
Molecular Sequence Data
;
Multigene Family
;
Phosphoprotein Phosphatases/*genetics/metabolism
;
Protein Kinases/metabolism
;
Protein Tyrosine Phosphatases
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
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