• Title/Summary/Keyword: Repressor

Search Result 163, Processing Time 0.034 seconds

Bach2 represses the AP-1-driven induction of interleukin-2 gene transcription in CD4+ T cells

  • Jang, Eunkyeong;Lee, Hye Rim;Lee, Geon Hee;Oh, Ah-Reum;Cha, Ji-Young;Igarashi, Kazuhiko;Youn, Jeehee
    • BMB Reports
    • /
    • v.50 no.9
    • /
    • pp.472-477
    • /
    • 2017

  • The transcription repressor Bach2 has been proposed as a regulator of T cell quiescence, but the underlying mechanism is not fully understood. Given the importance of interleukin-2 in T cell activation, we investigated whether Bach2 is a component of the network of factors that regulates interleukin-2 expression. In primary and transformed $CD4^+$ T cells, Bach2 overexpression counteracted T cell receptor/CD28- or PMA/ionomycin-driven induction of interleukin-2 expression, and silencing of Bach2 had the opposite effect. Luciferase and chromatin immunoprecipitation assays revealed that Bach2 binds to multiple Maf-recognition element-like sites on the interleukin-2 proximal promoter in a manner competitive with AP-1, and thereby represses AP-1-driven induction of interleukin-2 transcription. Thus, this study demonstrates that Bach2 is a direct repressor of the interleukin-2 gene in $CD4^+$ T cells during the immediate early phase of AP-driven activation, thereby playing an important role in the maintenance of immune quiescence in the steady state.

  • https://doi.org/10.5483/BMBRep.2017.50.9.124 인용 PDF KSCI

Phenotypic Stability of a Temperature-Controllable Expression Vector on Phenylalanine Production by Escherichia coli (대장균을 이용한 Phenylalanine 생산에 있어서 온도조절형 발현 Vector의 안정성)

  • 강상모;박인숙
    • Microbiology and Biotechnology Letters
    • /
    • v.19 no.5
    • /
    • pp.433-438
    • /
    • 1991

  • The plasmid pSY130-14 for the high production of phenylalanine is a temperaturecontrollable expression vector composed of the $P_R$ and the $P_L$ promoter and a temperature sensitive repressor, $cI_{857}$ of bacteriophage lambda. Strain AT2471 harbouring plasmid pSY13O- 14 is induced the phenylalanine production by shifting up the incubation temperaure to $38.5^{\circ}C$. Plasmid stability of E. coli AT2471 harbouring pSY130-14 was very low, it was about 30% after 48 h cultivation at $38.5^{\circ}C$ without kanamycin. The plasmid disappeared immediately at $40^{\circ}C$ without kanamycin, and at $40^{\circ}C$ adding kanamycin, the plasmid stability decreased at the beginning, but rose with the extension of the culture time. For the improvement of plasmid stability, the plasmid obtaind was designated as pSY15O-1 by changing origin region (ori) pACYC 177 of pSY130-14 for ori pSC101. E. coli AT2471 harbouring pSY150-1 was stable at $38.5^{\circ}C$ without tetracycline, and the plasrnid stability was about 40% after 48 h cultivation at $40^{\circ}C$.

  • PDF

Cloning and Characterization of the Paraquat Resistance-Related Genes from Ochrobactrum anthropi JW-2 (Ochrobactrum anthropi JW-2 유래의 Paraquat 내성유전자 PqrA의 주변 유전자군 분석)

  • Bae Eun-Kyung;Lee Hyo-Shin;Won Sung-Hye;Lee Byung-Hyun
    • Microbiology and Biotechnology Letters
    • /
    • v.34 no.1
    • /
    • pp.15-22
    • /
    • 2006

  • A 4,971 bp chromosomal DNA fragment containing the pqrA, paraquat resistance gene, was cloned from Ochrobactrum anthropi JW-2, and the complete nucleotide sequence was determined. Nucleotide and deduced amino acid sequences of the fragment revealed the presence of 4 complete ORFs (orf2, pqrA, orf3, orf4) and two incomplete ORFs(orf1, orf5). Orf1, pqrA, orf4 and orf5 exists at the direct strand but orf2 and orf3 exists at the reverse complementary strand. Orf1 which of incomplete sequences without start codon shares homology with ATP binding region of the response regulator receiver. Orf2 shares high homology with members of the tetR family of transcriptional repressor which have a helix-turn-helix (H-T-H) motif. Therefore, the orf2 is predicted as a transcriptional repressor of pqrA and is designated as pqrR2. Orf3 shares high homology with the members of the lysR family acting as a transcriptional activator which have both of a H-T-H motif at the N-terminal region and substrate binding domain at the C-terminal region. Therefore, the orf3 is predicted as a transcriptional activator of pqrA and is designated as pqrR1. Orf4 shows homology with the periplasmic substrate-binding protein of amino acid ABC transporter. Orf5 which of incomplete sequences without stop codon revealed the homology with the permeases protein of amino acid ABC transporter.

  • PDF KSCI

Mechanism of Regulation of the pts Promoter Transcription Initiation by Carbon Sources in Escherichia coli (Carbon Source의 변화에 의한 대장균의 pts Promoter 전사 조절 기작)

  • Kim, Soon-Young;Kwon, Hyuk-Ran;Shin, Dong-Woo;Ryu, Sang-Ryeol
    • Applied Biological Chemistry
    • /
    • v.42 no.4
    • /
    • pp.293-297
    • /
    • 1999

  • The pts operon, which encodes several factors in the phosphoenolpyruvate:carbohydrate phosphotransferase system (PTS) of Escherichia coli, has multiple promoters which respond to different signals to facilitate quick adaptation to changes in growth conditions. The influence of an 1 kbp DNA region upstream of the pts P0 promoter on pts expression was studied in vitro by employing the DNA templates containing both P0 and P1 promoter with or without the 1 kbp upstream DNA region for in vitro transcription assay. The 1 kbp DNA region upstream of the pts P0 promoter, however, had no effect on pts transcription in vitro. The intracellular concentration of cAMP was measured when cells were grown in the presence of glucose, mannose, or mannitol. The transcription of P0 was increased maximally in the presence of glucose even though the concentration of cAMP in the condition was lowest while the transcription from the P1b was highest when cells were grown in the presence of mannose or mannitol even though the intracellular concentration of cAMP was lower than cells grown in the absence of the sugar. These results suggest the possibility of the existence of a glucose inducible repressor specific for the P0 promoter and a second repressor that is inducible by glucose, mannose and mannitol specific for the P1 promoter.

  • PDF