A yeast gene important for protein assembly into the endoplasmic reticulum and the nucleus has homology to DnaJ, an Escherichia coli heat shock protein.

Sadler, Ingrid; Chiang, Ann‐Shyn; Kurihara, Takao; Rothblatt, Jonathan; Way, Jeffrey C.; Silver, Pamela A.

doi:10.1083/jcb.109.6.2665

Cited by 290 publications

(192 citation statements)

References 40 publications

Supporting

Mentioning

185

Contrasting

Unclassified

Order By: Relevance

“…Bound protein was divided into two samples, either with or without ?-mercaptoethanol to dissociate the cross-links, and run on a 4 -10% SDS polyacrylamide gel. For the experiment shown in Figure 2B, samples were prepared as described by Sadler et al (1989). For Western analysis, gels were blotted onto nitrocellulose in 50 mM Tris, 380 mM glycine, 0.1% SDS, and 20% methanol, blocked in 3% Carnation nonfat dry milk in 8 g/l NaCl, 0.2 g/l KCl, 3 g/l Tris, pH 8, and 0.1% Tween 20), and processed for immunodetection with antibody directed against HSF or against sp70 (the latter was the generous gift of E. A. Craig, University of Wisconsin, Madison, WI).…”

Section: Westerns and Coimmunoprecipitation Assaysmentioning

confidence: 99%

Complex Regulation of the Yeast Heat Shock Transcription Factor

Bonner

Carlson

Fackenthal

et al. 2000

MBoC

View full text Add to dashboard Cite

The yeast heat shock transcription factor (HSF) is regulated by posttranslational modification. Heat and superoxide can induce the conformational change associated with the heat shock response. Interaction between HSF and the chaperone hsp70 is also thought to play a role in HSF regulation. Here, we show that the Ssb1/2p member of the hsp70 family can form a stable, ATP-sensitive complex with HSF-a surprising finding because Ssb1/2p is not induced by heat shock. Phosphorylation and the assembly of HSF into larger, ATP-sensitive complexes both occur when HSF activity decreases, whether during adaptation to a raised temperature or during growth at low glucose concentrations. These larger HSF complexes also form during recovery from heat shock. However, if HSF is assembled into ATP-sensitive complexes (during growth at a low glucose concentration), heat shock does not stimulate the dissociation of the complexes. Nor does induction of the conformational change induce their dissociation. Modulation of the in vivo concentrations of the SSA and SSB proteins by deletion or overexpression affects HSF activity in a manner that is consistent with these findings and suggests the model that the SSA and SSB proteins perform distinct roles in the regulation of HSF activity. INTRODUCTIONIt has long been known that in cells of many species, including Escherichia coli and Saccharomyces cerevisiae, cell division rates are tightly coupled with the steady-state levels and rates of synthesis of ribosomal proteins and rRNA. For example, cells in rich media, with a short generation time, display higher abundance of rRNA and higher rates of synthesis of ribosomal proteins than do cells in poor media, with a long generation time. In E. coli, some of this regulation is achieved by transcriptional attenuation and translational regulation via binding of ribosomal proteins to the RNAs of target operons (Freedman et al., 1985;Cole and Nomura, 1986). In yeast, regulation is partly transcriptional, via RAP1 and its binding site, the upstream activating sequence (UAS) rpg (Herruer et al., 1987;Moehle and Hinnebusch, 1991;Kraakman et al., 1993), although much of the regulation of ribosomal protein abundance is achieved by a competition between the assembly into ribosomes and the rapid degradation of unassembled ribosomal proteins (Warner et al., 1985;Maicas et al., 1988).Growth rate control clearly modulates the level of the translational machinery, which in turn influences the overall rate of protein synthesis. Changes in the rates of protein synthesis must, in turn, have profound implications for the protein chaperone system. Newly synthesized polypeptides typically do not adopt their mature conformation immediately but instead follow a complex folding pathway. For many proteins, the cytoplasmic chaperone system plays an integral role in helping these polypeptides adopt their mature conformations (for review, see Hendrick and Hartl, 1995). The hsp70 proteins are generally believed to bind efficiently to nascent or newly synthesized polypeptides...

show abstract

Section: Westerns and Coimmunoprecipitation Assaysmentioning

confidence: 99%

Complex Regulation of the Yeast Heat Shock Transcription Factor

Bonner

Carlson

Fackenthal

et al. 2000

MBoC

View full text Add to dashboard Cite

show abstract

“…Rose et al, (1990) The SEC63 gene encodes an ER membrane protein with three hydrophobic regions (Sadler et al, 1989;Feldheim et al, 1992). The C-terminal two-thirds of Sec63p is located in the cytoplasm, whereas the region between the second and third hydrophobic regions is located in the ER lumen (Feldheim et al, 1992;Kurihara and Silver, 1992).…”

Section: Ms176mentioning

confidence: 99%

“…Plasmids pCS15 (CEN, LEU2, SEC61) and pRD15 (CEN, LEU2, SEC62) were the generous gift of Randy Schekman (University of California, Berkeley). The plasmids pTK1 (2g, LEU2, SEC63) and pMR397 (CEN, URA3, KAR2) have been described previously (Rose et al, 1989;Sadler et al, 1989). pHSS20 corresponds to the sec63-101 suppressing plasmid from the multicopy LEU2-based yeast genomic library of Nasmyth and Tatchell (1980).…”

Section: Plasmidsmentioning

confidence: 99%

“…Genes encoding homologues of mammalian SRP or SRP receptor components have been identified (Felici et al, 1989;Hann et al, 1989Hann et al, , 1992Amaya et al, 1990;Ogg et al, 1992;Stirling and Hewitt, 1992), and depletion of these homologs causes a translocation defect in vivo (Amaya and Nakano, 1991;Hann and Walter, 1991;Ogg et al, 1992;Stirling and Hewitt, 1992). Mutations in four essential genes (SEC61, SEC62, SEC63, and KAR2) are associated with translocation defects Schekman, 1987, 1989;Toyn et al, 1988;Sadler et al, 1989;Vogel et al, 1990;, and genetic and biochemical evidence indicates physical interactions between their protein products Deshaies et al, 1991;Scidmore, Okamura, and Rose, unpublished data). Sec6lp, Sec62p, and Kar2p can be cross-linked to translocating polypeptide chains in yeast ER membranes (Musch et al, 1992;Sanders et al, 1992), suggesting that they comprise components of a common translocation apparatus.…”

Section: Introductionmentioning

confidence: 98%

See 1 more Smart Citation

Suppression of a sec63 mutation identifies a novel component of the yeast endoplasmic reticulum translocation apparatus.

Kurihara

Silver

1993

MBoC

Self Cite

View full text Add to dashboard Cite

Mutations in the SEC63 gene are associated with defects in protein translocation into the endoplasmic reticulum (ER) as well as in nuclear protein localization in Saccharomyces cerevisiae. To identify proteins that might interact and/or function with SEC63p, we cloned a high copy suppressor (HSS1) of the temperature-sensitive lethal phenotype of the sec63-101 mutant. HSS1 is an allele-specific sec63 suppressor that encodes an integral ER membrane glycoprotein of 206 amino acids with the N-terminus in the ER lumen and C-terminal region in the cytoplasm. Haploid strains disrupted for HSS1 are temperature-sensitive for growth and accumulate precursor forms of Kar2p and invertase. The HSS1 null allele is synthetically lethal in combination with mutations affecting ER translocation. We propose that HSSlp is important for ER translocation and interacts with previously identified components of the yeast translocation apparatus. HSS1 is identical to SEC66, which encodes a glycoprotein complexed with SEC62p and SEC63p.

show abstract

“…Genetic studies in Saccharomyces cerevisiae have led to the identification of a number of genes involved in the translocation process (7)(8)(9)(10)(11)(12)(13). These include SEC61 that is an essential gene encoding the 53-kDa integral membrane protein, Sec61p (13).…”

mentioning

confidence: 99%

Determination of the Transmembrane Topology of Yeast Sec61p, an Essential Component of the Endoplasmic Reticulum Translocation Complex

Wilkinson

Critchley

Stirling

1996

Journal of Biological Chemistry

142

147

View full text Add to dashboard Cite

Sec61p is a highly conserved integral membrane protein that plays a role in the formation of a proteinconducting channel required for the translocation of polypeptides into, and across, the membrane of the endoplasmic reticulum. As a major step toward elucidating the structure of the endoplasmic reticulum translocation apparatus, we have determined the transmembrane topology of Sec61p using a combination of C-terminal reporter-domain fusions and the in situ digestion of specifically inserted factor Xa protease cleavage sites. Our data indicate the presence of 10 transmembrane domains, including several with surprisingly limited hydrophobicity. Furthermore, we provide evidence for complex intramolecular interactions in which these weakly hydrophobic domains require C-terminal sequences for their correct topogenesis. The incorporation of sequences with limited hydrophobicity into the bilayer may play a vital role in the formation of an aqueous membrane channel required for the translocation of hydrophilic polypeptide chains.

show abstract

A yeast gene important for protein assembly into the endoplasmic reticulum and the nucleus has homology to DnaJ, an Escherichia coli heat shock protein.

Cited by 290 publications

References 40 publications

Complex Regulation of the Yeast Heat Shock Transcription Factor

Complex Regulation of the Yeast Heat Shock Transcription Factor

Suppression of a sec63 mutation identifies a novel component of the yeast endoplasmic reticulum translocation apparatus.

Determination of the Transmembrane Topology of Yeast Sec61p, an Essential Component of the Endoplasmic Reticulum Translocation Complex

Contact Info

Product

Resources

About