scholarly journals Functional relationships between the Saccharomyces cerevisiae cis-prenyltransferases required for dolichol biosynthesis.

2005 ◽  
Vol 52 (1) ◽  
pp. 221-232 ◽  
Author(s):  
Kariona Grabińska ◽  
Grazyna Sosińska ◽  
Jacek Orłowski ◽  
Ewa Swiezewska ◽  
Thierry Berges ◽  
...  

In the yeast Saccharomyces cerevisiae the RER2 and SRT1 genes encode Rer2 and Srt1 proteins with cis-prenyltransferase (cis-PT-ase) activity. Both cis-PT-ases utilize farnesyl diphosphate (FPP) as a starter for polyprenyl diphosphate (dolichol backbone) formation. The products of the Rer2 and Srt1 proteins consist of 14-17 and 18-23 isoprene units, respectively. In this work we demonstrate that deletion or overexpression of SRT1 up-regulates the activity of Rer2p and dolichol content. However, upon overexpression of SRT1, preferential synthesis of longer-chain dolichols and a decrease in the amount of the shorter species are observed. Furthermore, overexpression of the ERG20 gene (encoding farnesyl diphosphate synthase, Erg20p) induces transcription of SRT1 mRNA and increases the levels of mRNA for RER2 and DPM1 (dolichyl phosphate mannose synthase, Dpm1p). Subsequently the enzymatic activity of Rer2p and dolichol content are also increased. However, the amount of Dpm1p or its enzymatic activity remain unchanged.

2020 ◽  
Vol 21 (23) ◽  
pp. 8938
Author(s):  
Sebastian Piłsyk ◽  
Urszula Perlinska-Lenart ◽  
Anna Janik ◽  
Elżbieta Gryz ◽  
Marta Ajchler-Adamska ◽  
...  

In a wide range of organisms, dolichyl phosphate mannose (DPM) synthase is a complex of tree proteins Dpm1, Dpm2, and Dpm3. However, in the yeast Saccharomyces cerevisiae, it is believed to be a single Dpm1 protein. The function of Dpm3 is performed in S. cerevisiae by the C-terminal transmembrane domain of the catalytic subunit Dpm1. Until present, the regulatory Dpm2 protein has not been found in S. cerevisiae. In this study, we show that, in fact, the Yil102c-A protein interacts directly with Dpm1 in S. cerevisiae and influences its DPM synthase activity. Deletion of the YIL102c-A gene is lethal, and this phenotype is reversed by the dpm2 gene from Trichoderma reesei. Functional analysis of Yil102c-A revealed that it also interacts with glucosylphosphatidylinositol-N-acetylglucosaminyl transferase (GPI-GnT), similar to DPM2 in human cells. Taken together, these results show that Yil102c-A is a functional homolog of DPMII from T. reesei and DPM2 from humans.


2017 ◽  
Vol 17 (4) ◽  
Author(s):  
Sebastián Rubat ◽  
Ignacio Varas ◽  
Romina Sepúlveda ◽  
Daniel Almonacid ◽  
Fernando González-Nilo ◽  
...  

1991 ◽  
Vol 11 (5) ◽  
pp. 2583-2592 ◽  
Author(s):  
C C Dykstra ◽  
K Kitada ◽  
A B Clark ◽  
R K Hamatake ◽  
A Sugino

The gene encoding the 180-kDa DNA strand transfer protein beta from the yeast Saccharomyces cerevisiae was identified and sequenced. This gene, DST2 (DNA strand transferase 2), was located on chromosome VII. dst2 gene disruption mutants exhibited temperature-sensitive sporulation and a 50% longer generation time during vegetative growth than did the wild type. Spontaneous mitotic recombination in the mutants was reduced severalfold for both intrachromosomal recombination and intragenic gene conversion. The mutants also had reduced levels of the intragenic recombination that is induced during meiosis. Meiotic recombinants were, however, somewhat unstable in the mutants, with a decrease in recombinants and survival upon prolonged incubation in sporulation media. spo13 or spo13 rad50 mutations did not relieve the sporulation defect of dst2 mutations. A dst1 dst2 double mutant has the same phenotype as a dst2 single mutant. All phenotypes associated with the dst2 mutations could be complemented by a plasmid containing DST2.


2011 ◽  
Vol 392 (6) ◽  
Author(s):  
Patrycja Zembek ◽  
Urszula Perlińska-Lenart ◽  
Katarzyna Rawa ◽  
Wioletta Górka-Nieć ◽  
Grażyna Palamarczyk ◽  
...  

AbstractInTrichoderma reesei, dolichyl phosphate mannose (dpm) synthase, a key enzyme in the O-glycosylation process, requires three proteins for full activity. In this study, thedpm2anddpm3genes coding for the DPMII and DPMIII subunits ofT. reeseiDPM synthase were cloned and functionally analyzed after expression in theSaccharomyces cerevisiae dpm1Δ[genotype (BY4743;his3Δ1; /leu2Δ0; lys2Δ0; /ura3Δ0; YPR183w::kanMX4] mutant. It was found that apart from the catalytic subunit DPMI, the DPMIII subunit is also essential to form an active DPM synthase in yeast. Additional expression of the DPMII protein, considered to be a regulatory subunit of DPM synthase, decreased the enzymatic activity. We also characterizedS. cerevisiaestrains expressing thedpm1,2,3ordpm1, 3genes and analyzed the consequences ofdpmexpression on protein O-glycosylationin vivoand on the cell wall composition.


2020 ◽  
Author(s):  
E. A. Alekseeva ◽  
T. A. Evstyukhina ◽  
V. T. Peshekhonov ◽  
V. G. Korolev

Abstract In eukaryotes, DNA damage tolerance (DDT) is determined by two repair pathways, homologous repair recombination (HRR) and a pathway controlled by the RAD6-epistatic group of genes. Monoubiquitylation of PCNA mediates an error-prone pathway, whereas polyubiquitylation stimulates an error-free pathway. The error-free pathway involves components of recombination repair; however, the factors that act in this pathway remain largely unknown. Here, we report that the HIM1 gene participates in error-free DDT. Notably, inactivation RAD30 gene encoding Polη completely suppresses him1-dependent UV mutagenesis. Furthermore, data obtained show a significant role of Polη in him1-dependent mutagenesis, especially at non-bipyrimidine sites (NBP sites). We demonstrate that him1 mutation significantly reduces the efficiency of the induction expression of RNR genes after UV irradiation. Besides, this paper presents evidence that significant increase in the dNTP levels suppress him1-dependent mutagenesis. Our findings show that Polη responsible for him1-dependent mutagenesis.


1988 ◽  
Vol 8 (3) ◽  
pp. 1282-1289
Author(s):  
W Haggren ◽  
D Kolodrubetz

The high-mobility-group (HMG) proteins, a group of nonhistone chromatin-associated proteins, have been extensively characterized in higher eucaryotic cells. To test the biological function of an HMG protein, we have cloned and mutagenized a gene encoding an HMG-like protein from the yeast Saccharomyces cerevisiae. A yeast genomic DNA library was screened with an oligonucleotide designed to hybridize to any yeast gene containing an amino acid sequence conserved in several higher eucaryotic HMG proteins. DNA sequencing and Northern (RNA) blot analysis revealed that one gene, called ACP2 (acidic protein 2), synthesizes a poly(A)+ RNA in S. cerevisiae which encodes a 27,000-molecular-weight protein whose amino acid sequence is homologous to those of calf HMG1 and HMG2 and trout HMGT proteins. Standard procedures were used to construct a diploid yeast strain in which one copy of the ACP2 gene was mutated by replacement with the URA3 gene. When this diploid was sporulated and dissected, only half of the spores were viable. About half of the nonviable spores proceeded through two or three cell divisions and then stopped dividing; the rest did not germinate at all. None of the viable spores contained the mutant ACP2 gene, thus proving that the protein encoded by ACP2 is required for cell viability. The results presented here demonstrate that an HMG-like protein has an essential physiological function.


1990 ◽  
Vol 10 (6) ◽  
pp. 2458-2467 ◽  
Author(s):  
R E Baker ◽  
D C Masison

CP1 is a sequence-specific DNA-binding protein of the yeast Saccharomyces cerevisiae which recognizes the highly conserved DNA element I (CDEI) of yeast centromeres. We cloned and sequenced the gene encoding CP1. The gene codes for a protein of molecular weight 39,400. When expressed in Escherichia coli, the CP1 gene directed the synthesis of a CDEI-binding protein having the same gel mobility as purified yeast CP1. We have given the CP1 gene the genetic designation CEP1 (centromere protein 1). CEP1 was mapped and found to reside on chromosome X, 2.0 centimorgans from SUP4. Strains were constructed in which most of CEP1 was deleted. Such strains lacked detectable CP1 activity and were viable; however, CEP1 gene disruption resulted in a 35% increase in cell doubling time and a ninefold increase in the rate of mitotic chromosome loss. An unexpected consequence of CP1 gene disruption was methionine auxotrophy genetically linked to cep1. This result and the recent finding that CDEI sites in the MET25 promoter are required to activate transcription (D. Thomas, H. Cherest, and Y. Surdin-Kerjan, J. Mol. Biol. 9:3292-3298, 1989) suggest that CP1 is both a kinetochore protein and a transcription factor.


1999 ◽  
Vol 145 (6) ◽  
pp. 1199-1208 ◽  
Author(s):  
Harold A. Fisk ◽  
Michael P. Yaffe

The smm1 mutation suppresses defects in mitochondrial distribution and morphology caused by the mdm1-252 mutation in the yeast Saccharomyces cerevisiae. Cells harboring only the smm1 mutation themselves display temperature-sensitive growth and aberrant mitochondrial inheritance and morphology at the nonpermissive temperature. smm1 maps to RSP5, a gene encoding an essential ubiquitin-protein ligase. The smm1 defects are suppressed by overexpression of wild-type ubiquitin but not by overexpression of mutant ubiquitin in which lysine-63 is replaced by arginine. Furthermore, overexpression of this mutant ubiquitin perturbs mitochondrial distribution and morphology in wild-type cells. Site-directed mutagenesis revealed that the ubiquitin ligase activity of Rsp5p is essential for its function in mitochondrial inheritance. A second mutation, smm2, which also suppressed mdm1-252 defects, but did not cause aberrant mitochondrial distribution and morphology, mapped to BUL1, encoding a protein interacting with Rsp5p. These results indicate that protein ubiquitination mediated by Rsp5p plays an essential role in mitochondrial inheritance, and reveal a novel function for protein ubiquitination.


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