28 research outputs found
Regulation of the expression of the Kluyveromyces lactis PDC1 gene: carbon source-responsive elements and autoregulation
The yeast Kluyveromyces lactis has a single structural gene coding for pyruvate decarboxylase (KIPDC1). In order to study the regulation of the expression of KIPDC1, we have sequenced (EMBL Accession No. Y15435) its promoter and have fused the promoter to the reporter gene lacZ from E. coli. Transcription analysis in a Klpdc1 delta strain showed that KIPDC1 expression is subject to autoregulation. The PDC1 gene from Saccharomyces cerevisiae was able to complement the Rag- phenotype of the Klpdc1 delta mutant strain and it could also repress transcription of the KIPDC1-lacZ fusion on glucose. A deletion analysis of the promoter region was performed to study carbon source-dependent regulation and revealed that at least two cis-acting regions are necessary for full induction of gene expression on glucose. Other cis-elements mediate repression on ethanol
The 'petite negative' yeast Kluyveromyces lactis has a single gene expressing pyruvate decarboxylase activity
We cloned and sequenced the pyruvate decarboxylase
(PDC; EC 4.1.1.1) structural gene KlPDCA in the
yeast Kluyveromyces lactis and found it to be allelic
to the previously isolated rag6 mutation. The putative
amino acid sequence of the KlPdcAp appeared to be
highly homologous to those of the yeast Pdc proteins
identified so far. The disruption of KIPDCA indicated
that it is the only PDC structural gene in K. lactis, as
evidenced by the lack of PDC activity and ethanol production
in the pdcAdelta strains and by the absence of
growth on glucose in the presence of respiratory inhibitors.
It was observed that expression of the KlPDCA
gene is induced by glucose at the transcriptional level.
Transcription of the gene was reduced in the ragl,
rag2, rag5 and rag8 mutants, which are defective for
the low-affinity glucose permease, phosphoglucose isomerase, hexokinase, and a positive regulator of RAG1
expression, respectively
Regulation of the expression of the Kluyveromyces lactis PDC1 gene: carbon source responsive elements and autoregulation.
The yeast Kluyveromyces lactis has a single structural gene coding for pyruvate decarboxylase (KlPDC1). In order
to study the regulation of the expression of KlPDC1, we have sequenced (EMBL Accession No. Y15435) its
promoter and have fused the promoter to the reporter gene lacZ from E. coli. Transcription analysis in a Klpdc1delta
strain showed that KlPDC1 expression is subject to autoregulation. The PDC1 gene from Saccharomyces cerevisiae was able to complement the Rag- phenotype of the Klpdc1delta mutant strain and it could also repress transcription of the KlPDC1–lacZ fusion on glucose. A deletion analysis of the promoter region was performed to study carbon source-dependent regulation and revealed that at least two cis-acting regions are necessary for full induction of gene expression on glucose. Other cis-elements mediate repression on ethanol