Genome-wide screening of Escherichia coli genes involved in execution and promotion of cell-to-cell transfer of non-conjugative plasmids: rodZ (yfgA) is essential for plasmid acceptance in recipient cells

The HSP30 gene of the budding yeast Saccharomyces cerevisiae encodes a seven-transmembrane heat shock protein expressed in response to various types of stress including heat shock. Although Hsp30p contains a potential N-glycosylation consensus sequence (Asn(2)-Asp(3)-Thr(4)), whether it is actually N-glycosylated has not been verified. Here we demonstrate that N-glycosylation is induced at Asn(2) of Hsp30p by severe heat shock, ethanol stress, and acetic acid stress. Mild heat shock and glucose depletion induced the expression but not N-glycosylation of Hsp30p, indicating the N-glycosylation to be dependent on temperature and environmental conditions. N-glycosylation did not affect on the intracellular localization of Hsp30p but its physiological role under severe heat shock conditions. Since limited information is available on stress-responsive or condition-induced N-glycosylation, our findings provide new insight into the regulation of cellular stress response in yeast.     

Two or more copies of Drosophila heat shock consensus sequence serve to activate transcription in yeast

A synthetic oligonucleotide bearing the Drosophila heat shock consensus sequence confers heat inducibility on a CYC1-lacZ gene in Saccharomyces cerevisiae. This sequence CTGGAATTTTCTAGA was inserted in place of the upstream activation sites of the CYC1 promoter adjacent to CYC1 TATA boxes. These constructs were transformed into yeast and found to be heat-inducible when two or more inserts were present. The level of inducibility seemed to increase with the number of inserted sequences: however, the orientations of these sequences relative to each other did not have much effect.