Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.1.27.3 (RNase T1)
 1,228 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We previously reported a genetic analysis of the growth-inhibitory effect caused by the overexpression of the Aspergillus oryzae rntA gene, encoding RNase T1 (Ribonuclease T1), in Saccharomyces cerevisiae. Subsequently, rns (ribonuclease T1 sensitive) mutants with mutations in the rns1 (DSL1), rns2 (UMP1), and rns3 (SEC17) genes, were identified. In the present study, rns4 (VPS32/SNF7) gene mutation was identified by complementation of tunicamycin sensitivity. While the rns4 mutant exhibited sensitivity to ambient stress conditions (200 mM CaCl(2), 1M NaCl and pH 8.0), genome-wide expression analysis revealed a similar pattern of genes up-regulated as was observed under nitrogen depletion condition by Gasch et al. [Mol. Biol. Cell 11 (2000) 4241]. Notably, the genes participating in autophagy (ATG4 and ATG8), the genes encoding a vacuolar protease (PRB1), vacuolar protease inhibitors (PAI3, PBI2 and TFS1) and YHR138c (a PBI2 homolog) were up-regulated in the rns4 mutant. Interestingly, the RNase T1*-GFP fusion protein (*inactive form) expressed in the rns4 mutant strain localized at the ER and vacuole under both stress or no-stress conditions. In contrast, the RNase T1*-GFP fusion protein expressed in the wild-type strain could not be detected under no-stress conditions, however, a stress-dependent localization of the fusion protein was observed at the vacuole. Since, the rns4 mutant exhibited a partial starvation-like response in spite of a rich ambient environment, leading to transportation of the secretory protein to the vacuole and accumulation in the endoplasmic reticulum, the present findings implicate a novel role for Rns4/Vps32 in proper response and adaptation to ambient conditions.
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PMID:Identification and characterization of rns4/vps32 mutation in the RNase T1 expression-sensitive strain of Saccharomyces cerevisiae: Evidence for altered ambient response resulting in transportation of the secretory protein to vacuoles. 1592 8

Overexpression of the rntA cDNA encoding RNase T1 derived from A. oryzae causes severe growth inhibition in S. cerevisiae. We previously reported that most S. cerevisiae mutant strains defective in translocation into the ER, ER-Golgi transport and vacuole formation exhibited hypersensitivity to expression of RNase T1. Screening for S. cerevisiae mutants that showed RNase T1 hypersensitivity resulted in the isolation of 38 (rns) mutant strains. Some of these mutants showed a variety of phenotypes including temperature-sensitive growth, hypersensitivity to G418, defect in invertase glycosylation and fragmented vacuoles. We identified the genes mutated in three of the rns mutants, rns1, rns2, and rns3, as DSL1, UMP1, and SEC17, respectively. Fluorescence microscopic observation showed that GFP or myc-tagged Rns1p was localized at the nuclear region in the cell. Two-hybrid screening revealed the interaction of Rns1p with a transcription factor Cin5p and a functionally unknown Ylr440cp. It was observed that HA-tagged Ylr440cp was localized to the ER and nuclear envelope.
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PMID:Isolation of Saccharomyces cerevisiae RNase T1 hypersensitive (rns) mutants and genetic analysis of the RNS1/DSL1 gene. 1594 68