JB
Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Lopez, N.
Right arrow Articles by Craig, E. A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Lopez, N.
Right arrow Articles by Craig, E. A.

Journal of Bacteriology, May 1999, p. 3136-3143, Vol. 181, No. 10
0021-9193/99/$04.00+0
Copyright © 1999, American Society for Microbiology. All rights reserved.

SSB, Encoding a Ribosome-Associated Chaperone, Is Coordinately Regulated with Ribosomal Protein Genes

Nelson Lopez,1 John Halladay,2 William Walter,2 and Elizabeth A. Craig2,*

Department of Biomolecular Chemistry2 and Department of Bacteriology,1 University of Wisconsin, Madison, Wisconsin 53706

Received 4 February 1999/Accepted 16 March 1999

Genes encoding ribosomal proteins and other components of the translational apparatus are coregulated to efficiently adjust the protein synthetic capacity of the cell. Ssb, a Saccharomyces cerevisiae Hsp70 cytosolic molecular chaperone, is associated with the ribosome-nascent chain complex. To determine whether this chaperone is coregulated with ribosomal proteins, we studied the mRNA regulation of SSB under several environmental conditions. Ssb and the ribosomal protein rpL5 mRNAs were up-regulated upon carbon upshift and down-regulated upon amino acid limitation, unlike the mRNA of another cytosolic Hsp70, Ssa. Ribosomal protein and Ssb mRNAs, like many mRNAs, are down-regulated upon a rapid temperature upshift. The mRNA reduction of several ribosomal protein genes and Ssb was delayed by the presence of an allele, EXA3-1, of the gene encoding the heat shock factor (HSF). However, upon a heat shock the EXA3-1 mutation did not significantly alter the reduction in the mRNA levels of two genes encoding proteins unrelated to the translational apparatus. Analysis of gene fusions indicated that the transcribed region, but not the promoter of SSB, is sufficient for this HSF-dependent regulation. Our studies suggest that Ssb is regulated like a core component of the ribosome and that HSF is required for proper regulation of SSB and ribosomal mRNA after a temperature upshift.

* Corresponding author. Mailing address: Department of Biomolecular Chemistry, 587 Medical Science Center, 1300 University Ave., Madison, WI 53706. Phone: (608) 263-7105. Fax: (608) 262-5253. E-mail: ecraig{at}facstaff.wisc.edu.

Journal of Bacteriology, May 1999, p. 3136-3143, Vol. 181, No. 10
0021-9193/99/$04.00+0
Copyright © 1999, American Society for Microbiology. All rights reserved.


This article has been cited by other articles:



Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
Appl. Environ. Microbiol. Infect. Immun. Eukaryot. Cell
Mol. Cell. Biol. J. Virol. Microbiol. Mol. Biol. Rev.
ALL ASM JOURNALS

Copyright © 1999 by the American Society for Microbiology. All rights reserved.