• 제목/요약/키워드: transcription elongation

검색결과 48건 처리시간 0.039초

Functional analysis of genes involved in rice disease resistance

  • S.H. Shin;S. R. Yun;Kim, Y C.;B. H. Cho
    • 한국식물병리학회:학술대회논문집
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    • 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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    • pp.80.1-80
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    • 2003
  • Several plant and microbial genes that could confer disease resistance in transgenic rice plants are being cloned and characterized. We are currently constructing transgenic rice lines that overexpress the gene products, such as a galactinol synthase, a defensin, and a bacterial ACC deaminase. Subtractive hybridization of a rice cDNA library constructed from the Xanthomonas oryzae-infected ice leaves resulted in isolation of many inducible cDNA clones including a elongation factor EF2, a oryzain alpha, a catalase, a aldehyde dehydrogenase, a S-adenosylmethionine synthetase, a caffeic acid O-methyltransferase, a glyceraldehyde-3-phosphate dehydrogenase, a light-regulated protein, nKY transcription factors, and a nucleotide diphosphate kinase. Some genes among those may be useful genetic sources for construction of disease resistant transgenic rice. Full lengths of the rice OsFIERG and a rice oryzain genomic clones were cloned, and serial deletion fragments of the promoter regions of these genes were fused with GUS reporter gene in pCAMBIA1201, respectively. Promoter activities of these constructs will be examined upon various stresses and Pathogen infections to obtain the pathogen specific inducible-promoter. This work was supported by a grant from BioGreen 21 Program, Rural Development Administration, Republic of Korea.

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Protein tRNA Mimicry in Translation Termination

  • Nakamura, Yoshikazu
    • 한국미생물생명공학회:학술대회논문집
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    • 한국미생물생명공학회 2001년도 Proceedings of 2001 International Symposium
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    • pp.83-89
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    • 2001
  • Recent advances in the structural and molecular biology uncovered that a set of translation factors resembles a tRNA shape and, in one case, even mimics a tRNA function for deciphering the genetic :ode. Nature must have evolved this 'art' of molecular mimicry between protein and ribonucleic acid using different protein architectures to fulfill the requirement of a ribosome 'machine'. Termination of protein synthesis takes place on the ribosomes as a response to a stop, rather than a sense, codon in the 'decoding' site (A site). Translation termination requires two classes of polypeptide release factors (RFs): a class-I factor, codon-specific RFs (RFI and RF2 in prokaryotes; eRFI in eukaryotes), and a class-IT factor, non-specific RFs (RF3 in prokaryotes; eRF3 in eukaryotes) that bind guanine nucleotides and stimulate class-I RF activity. The underlying mechanism for translation termination represents a long-standing coding problem of considerable interest since it entails protein-RNA recognition instead of the well-understood codon-anticodon pairing during the mRNA-tRNA interaction. Molecular mimicry between protein and nucleic acid is a novel concept in biology, proposed in 1995 from three crystallographic discoveries, one, on protein-RNA mimicry, and the other two, on protein-DNA mimicry. Nyborg, Clark and colleagues have first described this concept when they solved the crystal structure of elongation factor EF- Tu:GTP:aminoacyl-tRNA ternary complex and found its overall structural similarity with another elongation factor EF-G including the resemblance of part of EF-G to the anticodon stem of tRNA (Nissen et al. 1995). Protein mimicry of DNA has been shown in the crystal structure of the uracil-DNA glycosylase-uracil glycosylase inhibitor protein complex (Mol et al. 1995; Savva and Pear 1995) as well as in the NMR structure of transcription factor TBP-TA $F_{II}$ 230 complex (Liu et al. 1998). Consistent with this discovery, functional mimicry of a major autoantigenic epitope of the human insulin receptor by RNA has been suggested (Doudna et al. 1995) but its nature of mimic is. still largely unknown. The milestone of functional mimicry between protein and nucleic acid has been achieved by the discovery of 'peptide anticodon' that deciphers stop codons in mRNA (Ito et al. 2000). It is surprising that it took 4 decades since the discovery of the genetic code to figure out the basic mechanisms behind the deciphering of its 64 codons.

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원핵생물 711종의 보존적 유전자 탐색 (Investigation of Conservative Genes in 711 Prokaryotes)

  • 이동근;이상현
    • 생명과학회지
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    • 제25권9호
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    • pp.1007-1013
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    • 2015
  • 원핵생물체의 생명유지에 중요한 역할을 담당하는 유전자들을 밝히기 위해 미생물 유전체들 사이의 공통적 유전자를 파악하는 COG 알고리즘을 이용하였다. 원핵생물 711종 모두에 보존적인 것은 COG0080 (Ribosomal protein L11) 1개였다. 708종 이상의 원핵생물에 보존적인 22개의 ortholog 중 전사관련 2개, tRNA synthetase 관련4개, ribosamal large subunit 8개, ribosomal small subunit 7개였다. 700종 이상의 원핵생물에 보존적인 COG는 58개였다. 이중 리보좀을 구성하는 소단위체 등 번역 관련 COG가 50개(86.2%), 전사관련 COG가 4개(6.9%)로 나타나 생명현상에서의 단백질의 중요성을 알 수 있었다. 58개의 COG 중 보존성은 COG0060 (Isoleucyl tRNA synthetase)이 가장 높았고 COG0143 (Methionyl tRNA synthetase)이 가장 낮았다. 문(phylum)과 강(class) 수준에서 보존적 유전자들의 평균과 분산으로 유전체 분석을 수행한 결과 변이가 큰 고세균은 진정세균과 구분되었으며 편차는 일부 진정세균이 고세균보다 컸다. 보존적 유전자를 탐색하는 본 연구의 기법은 기초과학 연구와 함께 항균제 개발과 항암요법 개발 등에도 유용할 것이다.

Identification of Potential DREB2C Targets in Arabidopsis thaliana Plants Overexpressing DREB2C Using Proteomic Analysis

  • Lee, Kyunghee;Han, Ki Soo;Kwon, Young Sang;Lee, Jung Han;Kim, Sun Ho;Chung, Woo Sik;Kim, Yujung;Chun, Sung-Sik;Kim, Hee Kyu;Bae, Dong-Won
    • Molecules and Cells
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    • 제28권4호
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    • pp.383-388
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    • 2009
  • The dehydration responsive element binding protein 2C (DREB2C) is a dehydration responsive element/C-repeat (DRE/CRT)-motif binding transcription factor that induced by mild heat stress. Previous experiments established that overexpression of DREB2C cDNA driven by the cauliflower mosaic virus 35S promoter (35S:DREB2C) resulted in increased heat tolerance in Arabidopsis. We first analyzed the proteomic profiles in wild-type and 35S:DREB2C plants at a normal temperature ($22^{\circ}C$), but could not detect any differences between the proteomes of wild-type and 35S: DREB2C plants. The transcript level of DREB2C in 35S: DREB2C plants after treatment with mild heat stress was increased more than two times compared with expression in 35S:DREB2C plants under unstressed condition. A proteomic approach was used to decipher the molecular mechanisms underlying thermotolerance in 35S:DREB2C Arabidopsis plants. Eleven protein spots were identified as being differentially regulated in 35S:DREB2C plants. Moreover, in silico motif analysis showed that peptidyl-prolyl isomerase ROC4, glutathione transferase 8, pyridoxal biosynthesis protein PDX1, and elongation factor Tu contained one or more DRE/CRT motifs. To our knowledge, this study is the first to identify possible targets of DREB2C transcription factors at the protein level. The proteomic results were in agreement with transcriptional data.

Taxonomy of fungal complex causing red-skin root of Panax ginseng in China

  • Lu, Xiao H.;Zhang, Xi M.;Jiao, Xiao L.;Hao, Jianjun J.;Zhang, Xue S.;Luo, Yi;Gao, Wei W.
    • Journal of Ginseng Research
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    • 제44권3호
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    • pp.506-518
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    • 2020
  • Background: Red-skin root of Asian ginseng (Panax ginseng) significantly reduces the quality and limits the production of ginseng in China. The disease has long been thought to be a noninfectious physiological disease, except one report that proved it was an infectious disease. However, the causal agents have not been successfully determined. In the present study, we were to reveal the pathogens that cause red-skin disease. Methods: Ginseng roots with red-skin root symptoms were collected from commercial fields in Northeast China. Fungi were isolated from the lesion and identified based on morphological characters along with multilocus sequence analyses on internal transcription spacer, β-tubulin (tub2), histone H3 (his3), and translation elongation factor 1α (tef-1α). Pathogens were confirmed by inoculating the isolates in ginseng roots. Results: A total of 230 isolates were obtained from 209 disease samples. These isolates were classified into 12 species, including Dactylonectria sp., D. hordeicola, Fusarium acuminatum, F. avenaceum, F. solani, F. torulosum, Ilyonectria mors-panacis, I. robusta, Rhexocercosporidium panacis, and three novel species I. changbaiensis, I. communis, and I. qitaiheensis. Among them, I. communis, I. robusta, and F. solani had the highest isolation frequencies, being 36.1%, 20.9%, and 23.9%, respectively. All these species isolated were pathogenic to ginseng roots and caused red-skin root disease under appropriate condition. Conclusion: Fungal complex is the causal agent of red-skin root in P. ginseng.

분열효모에서 sphpr1 유전자의 결실이 생장 및 mRNA Export에 미치는 영향 (Effects of the Repression of sphpr1 Expression on Growth and mRNA Export in Fission Yeast)

  • 이현주;윤진호
    • 미생물학회지
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    • 제48권2호
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    • pp.171-174
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    • 2012
  • THOC1/Hpr1는 mRNA가 전사되는 동안 mRNP의 포장과 mRNA 방출에 관여하는 진화적으로 잘 보존된 THO 복합체의 한 소단위이다. 분열효모 Schizosaccharomyces pombe에서도 THOC1/Hpr1과 유사한 단백질을 암호화하는 유전자(sphpr1로 명명)를 찾아 그 특성을 조사하였다. 이배체 S. pombe 균주에 하나의 sphpr1 유전자만을 결실시킨 후 4분체 분석을 수행한 결과, 이 유전자는 생장에 필수적이었다. 티아민에 의해 발현이 조절되는 강력한 nmt1 프러모터를 이용하여 sphpr1를 과발현시키더라도 세포의 생장과 mRNA 방출에는 전혀 영향이 없었다. 하지만, sphpr1의 발현을 억제하면 생장이 억제되었으며 poly$(A)^+$ RNA가 핵 안에 축적되었다. 이와 같은 결과들은 sphpr1 유전자가 생장과 mRNA의 핵에서 세포질로의 방출에 관여하고 있음을 시사한다.

Systematic Studies of 12S Seed Storage Protein Accumulation and Degradation Patterns during Arabidopsis Seed Maturation and Early Seedling Germination Stages

  • Li, Qing;Wang, Bai-Chen;Xu, Yu;Zhu, Yu-Xian
    • BMB Reports
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    • 제40권3호
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    • pp.373-381
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    • 2007
  • Seed storage proteins (SSPs) are important for seed germination and early seedling growth. We studied the accumulation and degradation profiles of four major Arabidopsis 12S SSPs using a 2-DE scheme combined with mass spectrometric methods. On the 2-DE map of 23 dpa (days post anthesis) siliques, 48 protein spots were identified as putative full-length or partial $\alpha$, $\delta$ subunits. Only 9 of them were found in 12 dpa siliques with none in younger than 8 dpa siliques, indicating that the accumulation of 12S SSPs started after the completion of cell elongation processes both in siliques and in developing seeds. The length and strength of transcription activity for each gene determined the final contents of respective SSP. At the beginning of imbibition, 68 SSP spots were identified while only 2 spots were found at the end of the 4 d germination period, with $\alpha$, subunits degraded more rapidly than the $\alpha$ subunits. The CRC $\delta$ subunit was found to degrade from its C-terminus with conserved sequence motifs. Our data provide an important basis for understanding the nutritional value of developing plant seeds and may serve as a useful platform for other species.

애기장대에서 GmNAP1의 과발현으로 인한 엽록소 함량 증가 (Increase in the Chlorophyll Contents by Over-expression of GmNAP1 Gene in Arabidopsis Plant)

  • 박훤범;안철현
    • 생명과학회지
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    • 제20권10호
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    • pp.1563-1568
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    • 2010
  • 암(dark) 상태에서 재배한 대두의 하배축 길이 생장의 분자 기작을 연구하기 위한 일환으로 암 상태에서 재배한 대두 하배축으로부터 cDNA library를 제작한 후 ESTs를 구축하였다. 이들 ESTs 중 색소체 ABC 단백질과 아미노산 서열이 매우 유사한 clone을 선발한 후 이 유전자의 전체염기서열을 결정하였다. GmNAP1 단백질은 엽록체로 향하는 transit peptide 서열이 존재한다. 빛에 의해 GmNAP1 유전자 전사가 어떻게 변화되는지 알아보기 위해 지속적인 적색광, 근적색광 그리고 암 상태에서 성장시키면서 유전자의 전사량을 확인하였다. 이 색소체 NAP1는 엽록소의 전구 물질인 protoporphytin IX를 세포질에서 엽록체로 이동시키는 기능을 한다. 대두에서 분리된 GmNAP1 유전자의 기능을 확인하기 위하여 35S 프로모터 뒤에 GmNAP1 유전자를 접합한 후 애기장대에 형질전환하였다. 형질전환 된 애기장대의 엽록소 함량은 야생형의 엽록소 함량보다 훨씬 높게 측정되었다.

분열효모에서 spThoc7 유전자의 결실이 생장 및 mRNA Export에 미치는 영향 (Effects of spThoc7 Deletion on Growth and mRNA Export in Fission Yeast)

  • 고은진;윤진호
    • 미생물학회지
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    • 제50권3호
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    • pp.249-253
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    • 2014
  • THOC7/Mft1는 mRNA가 전사되는 동안 mRNP의 포장과 mRNA 방출에 관여하는 진화적으로 잘 보존된 THO 복합체의 구성인자이다. 분열효모 Schizosaccharomyces pombe에서 THOC7/Mft1의 이종상동체(spThoc7)가 합성치사 돌연변이체 SLRsm1의 생장 결함을 부분적으로 상보하는 것으로 선별되었다. 이배체 S. pombe 균주에 하나의 spthoc7 유전자만을 결실시킨 후 4분체 분석을 수행한 결과, 이 유전자는 생장에 필수적이지 않았다. 하지만, ${\Delta}thoc7$ 결실돌연변이는 생장과 mRNA의 핵에서 세포질로의 방출에 약간의 결함을 보였다. 기능을 하는 spThoc7-GFP단백질은 주로 핵 안에 존재하였다. 이와 같은 결과들은 spThoc7도 mRNA 방출에 관여하고 있음을 시사한다.

러시아 철갑상어(Acipenser gueldenstaedtii) 발생 시료의 RT-qPCR 분석을 위한 내재 대조군 유전자의 선정 (Evaluation of Candidate Housekeeping Genes for the Normalization of RT-qPCR Analysis using Developing Embryos and Prolarvae in Russian Sturgeon Acipenser gueldenstaedtii)

  • 남윤권;이상윤;김은정
    • 한국수산과학회지
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    • 제51권1호
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    • pp.95-106
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    • 2018
  • To evaluate appropriate reference genes for the normalization of quantitative reverse transcription PCR (RT-qPCR) data with embryonic and larval samples from Russian sturgeon Acipenser gueldenstaedtii, the expression stability of eight candidate housekeeping genes, including beta-actin (ACTB), elongation factor-1A (EF1A), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), histone 2A (H2A), ribosomal protein L5 (RPL5), ribosomal protein L7 (RPL7), succinate dehydrogenase (SDHA), and ubiquitin-conjugating enzyme E2 (UBE2A), were tested using embryonic samples from 12 developmental stages and larval samples from 11 ontogenic stages. Based on the stability rankings from three statistic software packages, geNorm, NormFinder, and BestKeeper, the expression stability of the embryonic subset was ranked as UBE2A>H2A>SDHA>GAPDH>RPL5>EF1A>ACTB>RPL7. On the other hand, the ranking in the larval subset was determined as UBE2A>GAPDH>SDHA>RPL5>RPL7>H2A>EF1A>AC TB. When the two subsets were combined, the overall ranking was UBE2A>SDHA>H2A>RPL5>GAPDH>EF1A>ACTB>RPL7. Taken together, our data suggest that UBE2A and SDHA are recommended as suitable references for developmental and ontogenic samples of this sturgeon species, whereas traditional housekeepers such as ACTB and GAPDH may not be suitable candidates.