• Journal of Life Science
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• v.12 no.2
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• pp.219-225
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• 2002

The organization of eukayotic chromatin into specific conformation that are associated with transcription, replication, reapir and other nuclear processes are achieved via a series of DNA-protein interaction. These interactions are mediated by a range of DNA-binding domains such as SAP domain et at. By searching S. pombe genomic DNA database, we have found a gene named SAPuvs (SAP UV Sensitive) whose amino acid sequence is in part similar to SAP domain of Arabidopsis poly (ADP-ribose) polymerase and Ku7O. Knock-out cell of S. pombe SAPuvs gene was constructed using Ura4 as a selection marker. Survival analysis of knock-out cell indicated that treatment with UV significantly reduces the survival compared to wild type cell. Potentiation of MMS-induced cytotoxicity by 3AB post-treatment was observed in wild type cells, but not in knock-out cells. These data suggested that the protein encoded by SAPuvs gene is associated with chromatin reorganization during DNA repair.

• Journal of Life Science
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• v.17 no.1 s.81
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• pp.39-44
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• 2007

The Rqh1 gene is essential for vegetative growth in fission Yeast. The rqh1 mutant showed that sensitivity of DNA damaging agent, a wild range of phenotype including abnormal gene expression and cell elongation. This result showed that the rqhl-overexpression cell was sensitivity to DNA damaging agent like rqhl mutant. When Rqh1 have an over-expression by $nmt1^+$ promoter of pREP vector, rqh1 mutant DNA damaging agent sensitivity could be compensated. We isolated two strong mutant containing complementation gene, rqh156 and rqh172, respectively. This result observed that the DNA damaging agent sensitivity of rqhl mutant was complemented by the expression of rqh156 and rqh172. They induced mRNA expression in a dose-dependent manner HU, MMS and UV. The HU sensitivity of the rqhl was complemented by the expression of rqh156 and rqh172. The mRNA expression of rqh156 decreased on HU dose dependent but the mRNA expression of rqh172 did not decrease on HU dose dependent. The MMS and W sensitivity of the rqhl was complemented by the expression of rqh156 and rqh172. These results indicate that the isolated rqhl gene may play an important role in DNA metabolism.

• Journal of Microbiology
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• v.43 no.1
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• pp.44-48
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• 2005

In our previous study, the first structural gene (GGTI) encoding ${\gamma}-glutamyl$ transpeptidase was cloned and characterized from the fission yeast Schizosaccharomyces pombe, and its transcription, using the GGTI-lacZ fusion gene, containing the 1,085 bp upstream region from the translational initiation point, was found to be enhanced by sodium nitroprusside and L-buthionine-(S,R)-sulfoximine (BSO). In the present work, regulation of the GGTI gene was further elucidated. Non-fermentable carbon sources, such as acetate and ethanol, markedly enhanced the synthesis of ${beta}-galactosidase$ from the GGTI-lacZ fusion gene. However, its induction by non-fermentable carbon sources appeared to be independent of the presence of the Pap1 protein. Nitrogen starvation also gave rise to induction of GGTI gene expression in a Pap1-independent manner. The three additional fusion plasmids, carrying 754, 421 and 156 bp regions, were constructed. The sequence responsible for the induction by non-fermentable carbon sources and nitrogen starvation was identified to exist within a -421 bp region of the GGTI gene. Taken together, the S. pombe GGTI gene is regulated by non-fermentable carbon sources and nitrogen starvation.

• Mycobiology
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• v.47 no.3
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• pp.301-307
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• 2019

The $11{\alpha}$-hydroxylation of $16{\alpha}$, 17-epoxyprogesterone (EP) catalyzed by Rhizopus nigricans is crucial for the steroid industry. However, lower conversion rate of the biohydroxylation restricts its potential industrial application. The $11{\alpha}$-steroid hydroxylase CYP509C12 from R. oryzae were reported to play a crucial role in the $11{\alpha}$-hydroxylation in recombinant fission yeast. In the present study, the CYP509C12 of R. oryzae (RoCYP) was introduced into R. nigricans using the liposome-mediated mycelial transformation. Heterologous expression of RoCYP resulted in increased fungal growth and improved intracellular reactive oxygen species content in R. nigricans. The $H_2O_2$ levels in RoCYP transformants were approximately 2-folder that of the R. nigricans wild type (RnWT) strain, with the superoxide dismutase activities increased approximately 45% and catalase activities decreased approximately 68%. Furthermore, the $11{\alpha}$-hydroxylation rates of EP in RoCYP transformants (C4, C6 and C9) were 39.7%, 38.3% and 38.7%, which were 12.1%, 8.2% and 9.4% higher than the rate of the RnWT strain, respectively. This paper investigated the effect of heterologous expression of RoCYP in R. nigricans, providing an effective genetic method to construct the engineered strains for steroid industry.

• Journal of Life Science
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• v.19 no.1
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• pp.101-110
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• 2009

The regulation of gene expression plays an important role in cell cycle controls. In this study, a novel $mas2^+$ (mitosis associated protein) gene, a homolog of human SMARCAD1 was isolated and characterized from a fission yeast Schizosaccharomyces pombe (S. pombe) using gene-specific polymerase chain reaction. The isolated gene contained a complete open reading frame capable of encoding 922 amino acid residues with a typical promoter, as judged by nucleotide sequence analysis. It was also found that an SNF2 domain is located, which is involved in the chromosome remodeling. The quantitative analysis of the $mas2^+$ transcript against $adh1^+$ showed that the expression level of $mas2^+$ is high before septum formation in S. pombe. When $mas2^+$ null mutant cells were grown at 27 and $35^{\circ}C$, the cytokinesis of $mas2^+$ null mutant was greatly delayed and a large number of multi-septate and mis-segregated cells were produced. In addition, the number of multi-septate cells significantly increased. When cells were cultured in YES rich medium to increase proliferation, the abnormal phenotypes $mas2^+$ null mutant dramatically increased. These phenotypes could be rescued by an over-expression of the mast gene. The Mas2 protein localized in the nuclei of S. pombe, as evidenced by Mas2-EGFP signals. These results suggest that the $mas2^+$ is homologous to human SMARCAD1 gene and involved in septum formation and chromosome remodeling control.

• The Korean Journal of Food And Nutrition
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• v.15 no.2
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• pp.112-118
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• 2002

Sporulation in the fission yeast Schizosaccharomyces pombe has been regarded as an important model of cellular development and differentiation. S. pombe cells proliferate by mitosis and binary fission on growth medium. Deprivation of nutrients especially nitrogen sources, causes the cessation of mitosis and initiates sexual reproduction by matting between two sexually compatible cell types. Meiosis is then followed in a diploid cell in the absence of nitrogen source. DNA fragment complemented with the mutations of sporulation gene was isolated from the S. pombe gene library constructed in the vector, pDB 248' and designated as pDB(spo5)1. We futher analyzed six recombinant plasmids, pDB(spo5)2, pDB(spo5)3, pDB(spo5)4, pDB(spo5)5, pDB (spo5)6, pDB(spo5)7 and found each of these plasmids is able to rescue the spo5-2, spo5-3, spo5-4, spo5-5, spo5-6, spo5-7 mutations, respectively. Mapping of the integrated plasmid into the homologous site of the S. pombe chromosomes demonstrated that pDB(spo5)1, and pDB(spu5)Rl contained the spo5 gene. Transcripts of spo5 gene were analyzed by Northern hybridization. Two transcripts of 3.2 kb and 2.5kb were detected with 5kb Hind Ⅲ fragment containing a part of the spo5 gene as a probe. The small mRNA(2.5kb) appeared only when a wild-type strain was cultured in the absence of nitrogen source in which condition the large mRNA (3.2kb) was produced constitutively. Appearance of a 2.5kb spo5-mRNA depends upon the function of the meil, mei2 and mei3 genes.

• Korean Journal of Microbiology
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• v.47 no.2
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• pp.110-116
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• 2011

In the previous study with the Saccharomyces cerevisiae S288c strains, no known function of the dual specificity kinase, ScKns1, was reported because its gene deletion did not show any noticeable phenotypic changes. Recent study with fission yeast, however, revealed the involvement of the LAMMER kinase in flocculation, filamentous growth, oxidative stress, and so on. Therefore we made Sckns1-deletion mutants with the ${\Sigma}1278b$-background, with which one can induce filamentous and adhesive growth in contrast to those of the S288c-background. The $Sckns1{\Delta}$ strains of both haploid and diploid showed defect in filamentous growth under conditions for inducing the filamentous growth such as nitrogen starvation and butanol treatment. Both kinds of the deletion mutants also showed decrease in adhesive growth on agar surface. Interestingly enough the defects of the $Sckns1{\Delta}$ strains were suppressed by the over-expression of each gene for the components of the MAPK signaling pathway such as STE11, STE12, and TEC1, respectively, but not by the upstream components, RAS2 and STE20, respectively. Although further investigations are required, these results indicate that the ScKns1 may act in place between the Ste20 and the Ste11 of the S. cerevisiae MAPK cascade.

• Proceedings of the Botanical Society of Korea Conference
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• 2002.04a
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• pp.62-72
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• 2002

This study has investigated the biosynthesis and function of the heavy metal binding peptides, the phytochelatins, in plants. PCs are synthesised enzymatically from glutathione by the enzyme PC synthase in the presence of heavy metal ions. Using Arabidopsis thaliana as a model organism cadmium-sensitive, phytochelatin-deficient mutants have been isolated and characterised in previous studies. The cadl mutants have wildtype levels of glutathione, are PC deficient and lack PC synthase activity. Thus, the CADl gene has been proposed to encode PC synthase. The CADl gene was isolated by a positional cloning strategy The gene was mapped and a candidate identified. Each of four cadl mutants had a single base pair change in the candidate gene and the cadmium-sensitive, cadl phenotype was complemented by the candidate gene. This demonstrated the CADl gene had been cloned. A homologous gene in the fission yeast, Schizosaccharomyces pombe was identified through database searches. A targeted-deletion mutation of this gene was constructed and the mutant, like cadl mutants of Arabidopsis, was cadmium-sensitive and PC-deficient. A comparison of the redicted amino acid sequences reveals a highly conserved N-terminal region Presumed to be the catalytic domain and a variable C-terminal region containing multiple Cys residues proposed to be involved in activation of the enzyme by metal ions. Similar genes were also identified in animal species. The Arabidopsis CADl/AtPCSl and S. pombe SpbPCS genes were expressed in E. coli and were shown to be sufficient for glutathione-dependent, heavy metal activate PC synthesis in vitro, thus demonstrating these genes encode PC synthase enzymes. Using RT-PCR, AtPCSl expression appeared to be independent of Cd exposure. However, at higher levels of Cd exposure a AtPCSl-CUS reporter gene construct appeared to be more highly expressed. Using the reporter gene construct, AtPCSl was expressed most tissues. Expression appeared to be greater in younger tissues and same higher levels of expression was observed in some regions, including carpels and the base of siliques. AtPCS2 was a functional gene encoding an active PC synthase. However, its Pattern of expression and the phenotype of a mutant (or antisense line) have not been determined. Assuming the gene is functional then it has clearly been maintained through evolution and must provide some selective advantage. This implies that, at least in some cells or tissue, it is likely to be the dominant PC synthase expressed. This remains to be determined

• Journal of Life Science
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• v.21 no.12
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• pp.1666-1677
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• 2011

The regulation of gene expression plays an important role in cell cycle controls. In this study, a novel gene, the $mas1^+$($\underline{mi}$tosis $\underline{as}$sociated protein) gene, a homolog of human CIP29/Hcc1, was isolated and characterized from fission yeast Schizosaccharomyces pombe (S. pombe) using a gene-specific polymerase chain reaction. The isolated gene contained a complete open reading frame capable of encoding 245 amino acid residues with a typical promoter, as judged by nucleotide sequence analysis. It was also found that a PCB ($\underline{p}$ombe cell $\underline{c}$ycle $\underline{b}$ox) is located in the promoter region, which controls M-$G_1$ specific transcription in S. pombe. The quantitative analysis of the $mas1^+$ transcript against $adh1^+$ showed that the pattern of expression is similar to that of the septation index. Cytokinesis of mas1 mutant was greatly delayed at $25^{\circ}C$ and $36^{\circ}C$, and a large number of multi-septate cells were produced. The mas1 mutant had 2C, 4C and 6C DNA contents, as determined by FACS analysis. In addition, the number of multi-septate cells significantly increased. When cells were cultured in nitrogen starvation medium to increase proliferation, the abnormal phenotypes of mas1 mutant dramatically increased. These phenotypes could be rescued by an overexpression of the $mas1^+$ gene. The mas1 protein localized in the nuclei of S. pombe and human HeLa cells, as evidenced by Mas1-EGFP signals. The abnormal growth pattern and the morphology of mas1 mutant were complemented by a plasmid carrying human CIP29/Hcc-1cDNA. In addition, CIP29 /Hcc-1 transcript level increased in active cell proliferation stages in the developing mouse embryos. These results indicate that the $mas1^+$ ishomologous to the human CIP29/Hcc1 gene and is involved in cytokinesis and cell shape control.