通过MAPKKKs或结合含SH3的渗透感受器激活酵母PBS2 MAPKK

Activation of yeast PBS2 MAPKK by MAPKKKs or by binding of an SH3-containing osmosensor.

作者信息

Maeda T, Takekawa M, Saito H

机构信息

Division of Tumor Immunology, Dana-Farber Cancer Institute, Boston, MA 02115, USA.

出版信息

Science. 1995 Jul 28;269(5223):554-8. doi: 10.1126/science.7624781.

DOI:10.1126/science.7624781

PMID:7624781

Abstract

The role of mitogen-activated protein (MAP) kinase cascades in integrating distinct upstream signals was studied in yeast. Mutants that were not able to activate PBS2 MAP kinase kinase (MAPKK; Pbs2p) at high osmolarity were characterized. Pbs2p was activated by two independent signals that emanated from distinct cell-surface osmosensors. Pbs2p was activated by MAP kinase kinase kinases (MAPKKKs) Ssk2p and Ssk22p that are under the control of the SLN1-SSK1 two-component osmosensor. Alternatively, Pbs2p was activated by a mechanism that involves the binding of its amino terminal proline-rich motif to the Src homology 3 (SH3) domain of a putative transmembrane osmosensor Sho1p.

摘要

在酵母中研究了丝裂原活化蛋白（MAP）激酶级联在整合不同上游信号中的作用。对在高渗透压下无法激活PBS2丝裂原活化蛋白激酶激酶（MAPKK；Pbs2p）的突变体进行了表征。Pbs2p由来自不同细胞表面渗透压感受器的两个独立信号激活。Pbs2p由受SLN1-SSK1双组分渗透压感受器控制的丝裂原活化蛋白激酶激酶激酶（MAPKKKs）Ssk2p和Ssk22p激活。另外，Pbs2p通过一种机制被激活，该机制涉及其富含脯氨酸的氨基末端基序与假定的跨膜渗透压感受器Sho1p的Src同源3（SH3）结构域结合。