Title: | Mapping regions in Ste5 that support Msn5-dependent and -independent nuclear export |
Author(s): | Hu Z; Wang Y; Yu L; Mahanty SK; Mendoza N; Elion EA; |
Address: | "Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 240 Longwood Avenue, Boston, MA 02115, USA" |
ISSN/ISBN: | 1208-6002 (Electronic) 0829-8211 (Linking) |
Abstract: | "Careful control of the available pool of the MAPK scaffold Ste5 is important for mating-pathway activation and the prevention of inappropriate mating differentiation in haploid Saccharomyces cerevisiae. Ste5 shuttles constitutively through the nucleus, where it is degraded by a ubiquitin-dependent mechanism triggered by G1 CDK phosphorylation. Here we narrow-down regions of Ste5 that mediate nuclear export. Four regions in Ste5 relocalize SV40-TAgNLS-GFP-GFP from nucleus to cytoplasm. One region is N-terminal, dependent on exportin Msn5/Ste21/Kap142, and interacts with Msn5 in 2 hybrid assays independently of mating pheromone, Fus3, Kss1, Ptc1, the NLS/PM, and RING-H2. A second region overlaps the PH domain and Ste11 binding site and 2 others are on the vWA domain and include residues essential for MAPK activation. We find no evidence for dependence on Crm1/Xpo1, despite numerous potential nuclear export sequences (NESs) detected by LocNES and NetNES1.1 predictors. Thus, Msn5 (homolog of human Exportin-5) and one or more exportins or adaptor molecules besides Crm1/Xpo1 may regulate Ste5 through multiple recognition sites" |
Keywords: | "Active Transport, Cell Nucleus Adaptor Proteins, Signal Transducing/*chemistry/*metabolism Cell Nucleus/chemistry/*metabolism Karyopherins/*metabolism Saccharomyces cerevisiae/cytology/metabolism Saccharomyces cerevisiae Proteins/*chemistry/*metabolism Ma;" |
Notes: | "MedlineHu, Zhenhua Wang, Yunmei Yu, Lu Mahanty, Sanjoy K Mendoza, Natalia Elion, Elaine A eng Research Support, Non-U.S. Gov't Canada 2016/01/30 Biochem Cell Biol. 2016 Apr; 94(2):109-28. doi: 10.1139/bcb-2015-0101. Epub 2016 Jan 29" |