| Title: | Two eukaryote-specific regions of Hsp82 are dispensable for its viability and signal transduction functions in yeast |
| Author(s): | Louvion JF; Warth R; Picard D; |
| Address: | "Department de Biologie Cellulaire, Universite de Geneve, Switzerland" |
| ISSN/ISBN: | 0027-8424 (Print) 1091-6490 (Electronic) 0027-8424 (Linking) |
| Abstract: | "The 90-kDa heat shock protein (Hsp90) is a molecular chaperone that is very abundant even at normal temperature. It is highly conserved and essential for viability in yeast. To delineate functional domains of Hsp90, we have performed a deletion analysis of one of the two Hsp90 isoforms from budding yeast, Hsp82. The Hsp82 derivatives were tested for complementation of a Hsp90-deficient yeast strain and for their ability to function in two signal transduction pathways that depend on Hsp90. Surprisingly, we found that two salient features of Hsp90 sequences from eukaryotes, the N-terminal charged domain and the extremely conserved C-terminal pentapeptide MEEVD, are dispensable for viability as well as for proper regulation of vertebrate steroid receptors and for pheromone signaling. Moreover, we describe, to our knowledge, the first dominant negative mutant of Hsp90; A Hsp82 derivative that lacks amino acids 538-552 fails to complement but has a dominant negative effect on viability of wild-type strains at moderately elevated temperatures. This mutant may become a valuable tool to study Hsp90 functions both in yeast and in mammalian cells" |
| Keywords: | "Amino Acid Sequence Conserved Sequence Estradiol/pharmacology Fungal Proteins/metabolism HSP90 Heat-Shock Proteins Heat-Shock Proteins/chemistry/genetics/*metabolism Humans Mutagenesis, Site-Directed Polymerase Chain Reaction Progesterone/pharmacology Rec;" |
| Notes: | "MedlineLouvion, J F Warth, R Picard, D eng Research Support, Non-U.S. Gov't 1996/11/26 Proc Natl Acad Sci U S A. 1996 Nov 26; 93(24):13937-42. doi: 10.1073/pnas.93.24.13937" |
