Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.26 (invertase)
 4,927 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The construction of two fused genes is described. One involves the in-frame fusion of the yeast prepro-alpha-factor coding sequence, and the Escherichia coli lac Z gene. The second gene fusion utilizes a 103 bp yeast invertase NH2-terminal coding sequence at the fusion junction of the hybrid gene described above. The gene fusions, under the control of the alpha-factor promoter, expressed active beta-galactosidase in alpha haploid yeast cells. The activity could be regulated in a temperature-sensitive sir3 mutant. The incorporation of the invertase coding sequence at the MF alpha 1-lacZ fusion junction provided significantly higher levels of beta-galactosidase activity. A substantial quantity of the hybrid proteins generated from the gene fusions was primarily localized in the intracellular membranes of yeast cells, while a processed form could be secreted into the periplasm.
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PMID:Alpha-factor leader sequence-directed transport of Escherichia coli beta-galactosidase in the secretory pathway of Saccharomyces cerevisiae. 250 25

Yeast secretory mutant sec53 cells accumulate inactive secretory glycoprotein precursors that remain associated with the endoplasmic reticulum (ER) at the restrictive temperature (37 degrees C). The possibility that precursor polypeptides fail to penetrate completely into the ER lumen was tested by examining the protease accessibility of accumulated invertase, mating pheromone precursor prepro-alpha-factor and the vacuolar protein precursor procarboxypeptidase Y in cell lysates. In all three cases, the secretory protein precursors are protected from the action of exogenous protease unless the membrane is permeabilized by including Triton X-100 or saponin in the incubation. These results suggest that the sec53 defect allows complete polypeptide translocation. Consistent with this interpretation, the precursor of invertase accumulates in a signal peptide-processed form. In addition, invertase and prepro-alpha-factor precursors contain a small amount of possibly aberrant carbohydrate. In mutant cells or in wild type cells treated with tunicamycin, a 10-kDa fragment of the N terminus of mature invertase assumes a conformation that is resistant to trypsin with or without detergent. This domain may be associated with an ER protein or may simply assume an unusual conformation as a consequence of deficient glycosyl modification.
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PMID:Product of SEC53 is required for folding and glycosylation of secretory proteins in the lumen of the yeast endoplasmic reticulum. 329 55