ISSN:
0749-503X
Keywords:
S. cerevisiae
;
β1,6-glucan synthesis
;
duplicated enzymatic activity
;
carbon-source-dependent transcriptional regulation
;
Life Sciences
;
Life Sciences (general)
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
Notes:
The KNH1 gene from Saccharomyces cerevisiae was identified as an open reading frame on the right arm of chromosome IV. The product encoded by the KNH1 gene, Knh1p, shares 46% overall identity with Kre9p, a protein required for cell surface β1,6-glucan synthesis. While disruption of the KNH1 locus had no effect on cell growth, killer toxin sensitivity or β1,6-glucan levels, overexpression of KNH1 was found to suppress the severe growth defect of a kre9Δ mutant and restored the level of alkali-insoluble β1,6-glucan to almost wild-type levels. Knh1p, like Kre9p, can be found in the extracellular culture medium as an O-glycoprotein, with a molecular mass of 45-61 kDa. Disruption of both KNH1 and KRE9 is lethal, and unlike single kre9Δ mutants, could not be rescued by overproducing SKN7, a putative transcription factor involved in the regulation of extracellular matrix assembly. Transcription of KNH1 was found to be carbon-source and kre9Δ dependent, but SKN7 independent, suggesting that KNH1 is subject to alternative transcriptional control. The KNH1 sequence has been deposited in GenBank under Accession Number U31538.
Additional Material:
4 Ill.
Type of Medium:
Electronic Resource
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