• Journal of Microbiology and Biotechnology
• /
• v.25 no.2
• /
• pp.152-161
• /
• 2015

CodY is a highly conserved protein in low G+C gram-positive bacteria that regulates genes involved in sporulation and stationary-phase adaptation. Bacillus thuringiensis is a grampositive bacterium that forms spores and parasporal crystals during the stationary phase. To our knowledge, the regulatory mechanism of CodY in B. thuringiensis is unknown. To study the function of CodY protein in B. thuringiensis, BMB171codY^- was constructed in a BMB171 strain. A shuttle vector containing the ORF of cry1Ac10 was transformed into BMB171 and BMB171codY^-, named BMB171cry1Ac and BMB171codY^-cry1Ac, respectively. Some morphological and physiological changes of codY mutant BMB171codY^-cry1Ac were observed. A comparative proteomic analysis was conducted for both BMB171codY^-cry1Ac and BMB171cry1Ac through two-dimensional gel electrophoresis and MALDI-TOF-MS/MS analysis. The results showed that the proteins regulated by CodY are involved in microbial metabolism, including branched-chain amino acid metabolism, carbohydrate metabolism, fatty acid metabolism, and energy metabolism. Furthermore, we found CodY to be involved in sporulation, biosynthesis of poly-β-hydroxybutyrate, growth, genetic competence, and translation. According to the analysis of differentially expressed proteins, and physiological characterization of the codY mutant, we performed bacterial one-hybrid and electrophoretic mobility shift assay experiments and confirmed the direct regulation of genes by CodY, specifically those involved in metabolism of branched-chain amino acids, ribosomal recycling factor FRR, and the late competence protein ComER. Our data establish the foundation for in-depth study of the regulation of CodY in B. thuringiensis, and also offer a potential biocatalyst for functions of CodY in other bacteria.

• Journal of Plant Biotechnology
• /
• v.5 no.4
• /
• pp.209-214
• /
• 2003

Expression of 43 flowering-related genes was examined in two inbred lines of Chinese cabbage, Chiifu and Kenshin, under different photoperiod, vernalization and flower development stages. The floral genes cloned by RT-PCR with degenerated primers showed high homology with Arabidopsis counterparts. Genes in two inbred lines, TOC, CRY1, CO, RGAL and GAl, were highly expressed under all tested conditions. However, expression of three genes was regulated by particular experimental conditions. The expression of LHY gene was predominant in Chiifu under the short-day conditions, whereas the expression of RGAL gene was influenced by vernalization in both inbred lines. Besides, the expression of NAP gene was induced by vernalization only in Chiifu. Most of the flower identity-related genes were expressed during flower development. The transcript level for several genes was not detected in this experiment.

• Journal of Microbiology and Biotechnology
• /
• v.18 no.6
• /
• pp.1033-1039
• /
• 2008

A 3-kb HindIII fragment bearing the cry6Aa2 gene and the adjacent and intergenic regions was cloned from Bacillus thuringiensis strain YBT-1518. Two open reading frames (ORFs), namely, orf1 (termed cry6Aa2) and orf2 that were separated by an inverted-repeat sequence were identified. orf1 encoded a 54-kDa protein that exhibited high toxicity to the plant-parasitic nematode Meloidogyne hapla. The orf2 expression product was not detected by SDS-PAGE, but its mRNA was detected by RT-PCR. The orf2 coexpressed with orf1 at a high level in the absence of the inverted-repeat sequence, whereas, the expression level of otfl was decreased. When orf2 was mutated, the level of orf1 expression was enhanced obviously. In conclusion, the inverted-repeat sequence disturbs orf2 expression, and the orf2 downregulates orf1 expression. This is an example of novel negative regulation in B. thuringiensis and a potential method for enhancing the expression level of cry genes.

• Development and Reproduction
• /
• v.8 no.1
• /
• pp.57-64
• /
• 2004

This study was carried out to examine the expression of the circadian clock genes in the mouse ovary and testis at different developmental stages. Expression of Period1(Per 1), Period2(Per2), Period3(Per3), Cryptochrome1(Cry1), Cyptochrome2(Cry2), Clock Small and Prokineticin1 and Prokineticin2 receptor(Prok1r, Prok2r) genes in mouse ovary was explored by semiquantitative reverse transcription Polymerase chain reaction(RT-PCR) according to the developmental stage(post partum day; ppd 1, 7, 10, 21 and 35). Immunohistochemistry using PER1 antibody was also analyzed. The differential expression pattern of clock genes was presented according to stages of the mouse ovarian development (ppd 1, 7, 10, 21 and 35). In the cases of ovaries, at the starting point of follicle growth at ppd 7 and 10, the clock gene expression patterns were changed vastly. According to the developmental stages, the clock genes were highly expressed at ppd 7 and 10 in mouse testis also. Receptors for Prok2, the circadian output molecule of SCN, were also expressed in ovary at ppd 7 and in testis at ppd 1 and 7, respectively. Immnunohistochemical analysis of PER1 showed positive signals in the cytoplasm of oocytes and granulosa cells. The level or PER1 expression was increased in cells at the spermatogonia and the condensing spermatids. The expression pattern of Perl and localization of PER1 were showed similar patterns according to the developmental stages in ovary and testis. Taken together, it could be observed that the expression of clock genes was highly correlated with gonadal development and germ cell differentiation in mice. Therefore, in this study, circadian programming of the genes in the ovary and testis is strongly imposed across a wide range of core reproductive cycles and normal development of gametes. Although the existence of circadian genes is clearly investigated, further studies on the direct evidence is required for the understanding of the relationship between circadian genes and regulation of gonadal differentiation and germ cell development.

• Research in Plant Disease
• /
• v.15 no.3
• /
• pp.202-208
• /
• 2009

The genetically modified leaffolder-resistant (Cry1Ac1) rice plant was evaluated for the changes of resistance by comparing the occurrence of major diseases with a japonica type Korean rice variety, Nakdong which was the mother plant of the transgenic rice event, in greenhouse and field conditions. There was no difference in the occurrence of sheath blight and Helminthosporium blight between the two varieties in the fields. We couldn't find any difference of resistance for fungal blast and bacterial leaf blight by artificial inoculation in greenhouse. There was also no difference in the susceptibility to sheath blight in artificial inoculation tests confirming the results in the fields. The possibility of gene transfer of Bar and Cry1Ac1 from the genetically modified rice plant to naturally infected pathogens such as Fusarium moniliforme and Pyricularia oryzae in the field conditions was tested by PCR. And the possible transfer of those genes by continuous inoculation of Xanthomonas oryzae pv. oryzae and Rhizoctonia solani was also tested. However, we couldn't find any possibility of transfer of the genes in natural and artificial conditions.

• Biomedical Science Letters
• /
• v.12 no.1
• /
• pp.53-56
• /
• 2006

The suprachiasmatic nucleus (SCN) of the anterior hypothalamus is the circadian pacemaker entrained to the 24-hr day by environmental time cues. Major circadian genes such as mPeriod ($mPer1{\sim}3$) and mCryptochrome ($mCry1{\sim}2$) are actively transcribed by the action of CLOCK/BMAL heterodimers, and in turn, these are being suppressed by the mPER/mCRY complex. In the study, the locomotor activity rhythms of mPer1 Knockout (KO) mice are measured, and the expression profiles of Heat Shock Protein 105kDa (HSP 105) genes in the SCN were measured by in situ hybridization. In agreement with previous reports, the locomotor activity rhythm of mPer1 KO mice was much shorter than that of wildtype. In addition, the total bout of activity of mPer1 KO was less in comparison to control mice. The expression of HSP 105 in the SCN of mPer1 KO mice was ranged from CT6 to CT22, with a peak level at CT14, implying that the gene are under the control of circadian clock. However, the expression of HSP 105 in the SCN of wildtype could not be detected in our study. Further analysis will reveal the direct or indirect regulation by mPer1 on the expression in the SCN and the role of the gene in the circadian clock.

• Plant Biotechnology Reports
• /
• v.3 no.4
• /
• pp.285-292
• /
• 2009

Zoysiagrass (Zoysia japonica) is one of the important turfgrass species. Extending green period of zoysiagrass via delaying leaf senescence will make this species have more potential in the turfgrass industry. In this study, we found that zoysiagrass seedlings treated with $GA_3$ could delay the leaf senescence induced by darkness. To study expression of genes responsive to staying green in zoysiagrass, suppression subtractive hybridization (SSH) was used to identify differentially expressed genes between non-$non-GA_3-treated$ and $GA_3-treated$ seedlings subjected to darkness. A total of 307 ESTs were generated, of which 226 ESTs clustered into 54 contigs and 81 were singlets. Differentially expressed genes selected by subtractions were classified into six categories according to their putative functions generated by BLAST analysis. Expression of five selected genes, Met, SAM, V-ATPase, Cry (Cryptochrome gene), and An (diphthine synthase gene) were examined by RT-PCR and Real-time PCR. Both RT-PCR and Real-time PCR results demonstrated that the differential expressions of these genes were attributable to delaying senescence by exogenously applied gibberellic acid. This is the first genome-wide study of senescence in a species of turfgrass.

• Proceedings of the Korean Society of Applied Entomolohy Conference
• /
• 2004.05a
• /
• pp.67-67
• /
• 2004

• Proceedings of the Korean Society of Sericultural Science Conference
• /
• 2005.04a
• /
• pp.49-49
• /
• 2005

• Proceedings of the Korean Society of Sericultural Science Conference
• /
• 2004.10a
• /
• pp.77-77
• /
• 2004