Pyruvate kinase type M2 is phosphorylated at tyrosine residues in cells transformed by Rous sarcoma virus

FEBS Letters

Reinacher, Manfred³  Presek, Peter²  Eigenbrodt, Erich¹ 

[1] Institut für Biochemie und Endokrinologie, Justus Liebig-Universität Gießen, 63 Gießen, FRG;Rudolf Buchheim-Institut für Pharmakologie, Justus Liebig-Universität Gießen, 63 Gießen, FRG;Institut für Veterinär-Pathologie, Justus Liebig-Universität Gießen, 63 Gießen, FRG

关键词: Pyruvate kinase;    Tyrosine phosphorylation;    Transformation;    (Rous sarcoma virus);    CEC;    chicken embryo cell;    RSV;    Rous sarcoma virus;    SR-A;    Schmidt-Ruppin strain of RSV;    subgroup A;    ts-NY 68;    temperature-sensitive mutant of RSV;    New York 68;    PK;    pyruvate kinase (EC 2.7.1.40);    M2-PK;    PK type M2;    HPT;    hydroxyapatite;   

DOI  :  10.1016/0014-5793(88)81014-7

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Chicken embryo cells (CECs) contain pyruvate kinase (PK) type M₂ (M₂-PK). Transformation of CECs by Rous sarcoma virus (RSV) leads to a reduction in the affinity of PK for the substrate phosphoenolpyruvate. In vitro, M₂-PK can be phosphorylated at tyrosine residues by pp60^v-src, the transforming protein of RSV. To study tyrosine phosphorylation of M₂-PK in intact RSV-transformed cells, the protein was immunoprecipitated from ³²P-labeled normal and RSV-SR-A-transformed CECs. Phosphoamino acid analysis of immunoprecipitated M₂-PK revealed that M₂-PK of both normal and transformed CECs contained phosphoserine and small amounts of phosphothreonine. Only M₂-PK of transformed CECs contained phosphotyrosine in addition. For enzyme kinetic studies M₂-PK was partially purified by chromatography upon DEAE-Sephacel and hydroxyapatite. A decreased affinity for phosphoenolpyruvate was observed 3 h after the onset of transformation using the temperature-sensitive mutant of RSV, ts-NY 68. The kinetic changes were correlated with tyrosine phosphorylation of M₂-PK, but there is no direct evidence that they are caused by post-translational modification of the enzyme.

【 授权许可】

Unknown