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PubMed · 2464757

AtT20 cells express modified forms of pp60c-src.

K L Gould·L M Bilezikjian·T Hunter
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Abstract

We have compared the properties of pp60c-src from the mouse pituitary tumor cell line, AtT20, and from mouse fibroblasts. In vitro, pp60c-src phosphotransferase activity from AtT20 cells is 2- to 3-fold that of mouse NIH 3T3 fibroblast pp60c-src. In analyzing the reason for this elevation in specific activity, we found that pp60c-src from AtT20 cells differs structurally in at least three ways from pp60c-src in fibroblasts. First, AtT20 cells and primary rat anterior pituitary cells express low levels of the neuronal form of pp60c-src. Second, pp60c-src from AtT20 cells is phosphorylated at two additional N-terminal serine residues. Last, AtT20 pp60c-src is phosphorylated to a lower overall stoichiometry.

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Acid PhosphataseAnimalsElectrophoresis, Polyacrylamide GelFibroblastsImmunosorbent TechniquesIsoelectric PointMiceMyristic AcidMyristic AcidsNeuronsPhosphorylationPhosphotransferasesPituitary GlandPituitary NeoplasmsProtein-Tyrosine KinasesProto-Oncogene ProteinsProto-Oncogene Proteins pp60(c-src)Tumor Cells, CulturedComparative StudyJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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K L Gould, L M Bilezikjian, T Hunter. 1989. AtT20 cells express modified forms of pp60c-src.. https://doi.org/10.1210/mend-3-1-79

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