来自产朊假丝酵母和乳酸克鲁维酵母的候选渗透压感受器：与酿酒酵母中Sho1p假定渗透压感受器的结构和功能同源性。

Candidate osmosensors from Candida utilis and Kluyveromyces lactis: structural and functional homology to the Sho1p putative osmosensor from Saccharomyces cerevisiae.

作者信息

Siderius M, Kolen C P, van Heerikhuizen H, Mager W H

机构信息

Department of Biochemistry and Molecular Biology, IMBW, Biocentrum Amsterdam, Vrije Universiteit, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands.

出版信息

Biochim Biophys Acta. 2000 Dec 15;1517(1):143-7. doi: 10.1016/s0167-4781(00)00231-1.

DOI:10.1016/s0167-4781(00)00231-1

PMID:11118628

Abstract

In Saccharomyces cerevisiae, increases in external osmolarity evoke osmostress-induced signalling via the HOG MAP kinase pathway. One of the upstream components of this signal transduction route is the putative osmosensor, Sho1p. With the aim to elucidate the molecular basis of osmosensing in budding yeast, we have cloned SHO1 homologues from Candida utilis and Kluyveromyces lactis which allowed determination of conserved domains of Sho1p. Results obtained from sequence comparisons, confirmed the importance of the transmembrane domains and the SH3 domain for Sho1p function. The K. lactis and S. cerevisiae Sho1p show the highest degree of homology, the isoform from C. utilis is a shorter protein. SHO1 from C. utilis, however, did complement the osmosensitivity of the sho1ssk2ssk22 strain by restoring HOG pathway function, since Hog1p dual phosphorylation after high osmotic challenge was restored in this strain after transformation with a plasmid bearing this SHO1 homologue.

摘要

在酿酒酵母中，外部渗透压的升高会通过高渗甘油（HOG）丝裂原活化蛋白激酶途径引发渗透应激诱导的信号传导。该信号转导途径的上游成分之一是假定的渗透压感受器Sho1p。为了阐明芽殖酵母中渗透压感应的分子基础，我们从产朊假丝酵母和乳酸克鲁维酵母中克隆了SHO1同源物，这使得能够确定Sho1p的保守结构域。序列比较结果证实了跨膜结构域和SH3结构域对Sho1p功能的重要性。乳酸克鲁维酵母和酿酒酵母的Sho1p显示出最高程度的同源性，产朊假丝酵母的同种型是一种较短的蛋白质。然而，产朊假丝酵母的SHO1确实通过恢复HOG途径功能来弥补sho1ssk2ssk22菌株的渗透敏感性，因为在用携带该SHO1同源物的质粒转化后，该菌株在高渗挑战后Hog1p的双磷酸化得以恢复。