• 제목/요약/키워드: premature stop codon

검색결과 17건 처리시간 0.023초

Cloning and Characterization of ${\Delta}^1$-Pyrroline-5-Carboxylate Synthetase Genes and Identification of Point Mutants in Medicago truncatula

  • Song, Ki-Hoon;Song, Dae-Hae;Lee, Jeong-Ran;Kim, Goon-Bo;Choi, Hong-Kyu;Penmetsa, R. Varma;Nam, Young-Woo
    • 한국작물학회지
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    • 제52권4호
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    • pp.458-468
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    • 2007
  • To tolerate environmentally adverse conditions such as cold, drought, and salinity, plants often synthesize and accumulate proline in cells as compatible osmolytes. ${\Delta}^1$-Pyrroline-5-carboxylate synthetase(P5CS) catalyzes the rate-limiting step of proline biosynthesis from glutamate. Two complete genes, MtP5CS1 and MtP5CS2, were isolated from the model legume Medicago truncatula by cDNA cloning and bacterial artificial chromosome library screening. Nucleotide sequence analysis showed that both genes consisted of 20 exons and 19 introns. Alignment of the predicted amino acid sequences revealed high similarities with P5CS proteins from other plant species. The two MtP5CS genes were expressed in response to high salt and low temperature treatments. Semi-quantitative reverse transcription-polymerase chain reaction showed that MtP5CS1 was expressed earlier than MtP5CS2, indicating differential regulation of the two genes. To evaluate the reverse genetic effects of nucleotide changes on MtP5CS function, a Targeting Induced Local Lesions in Genomes approach was taken. Three mutants each were isolated for MtP5CS1 and MtP5CS2, of which a P5CS2 nonsense mutant carrying a codon change from arginine to stop was expected to bring translation to premature termination. These provide a valuable genetic resource with which to determine the function of the P5CS genes in environmental stress responses of legume crops.

Genomics Approach to Identify the Cause of the Missing Omega-5 Gliadin Protein in O-Free Wheat

  • Lee, Yun Gyeong;Choi, Sang Chul;Kang, Yuna;Kang, Chon-Sik;Kim, Changsoo
    • Plant Breeding and Biotechnology
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    • 제6권4호
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    • pp.413-425
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    • 2018
  • A previous work developed and identified a new omega-5 gliadin deficient wheat line named O-free by crossing Keumkang and Olgeuru, which is nutritionally quite meaningful in that omega-5 gliadin is one of the known wheat allergens. To verify the characteristics of the O-free, we performed RNA sequencing (RNAseq) analysis of the O-free and the two parent lines (Keumkang and Olgeuru). The results of the similarity analysis with the ESTs for gliadins and glutenins showed that the O-free ESTs had no similarity with the omega-5 gliadin sequences but had similarity to other gliadins and glutenins. Furthermore, mapping results between the raw RNAseq data from the O-free and the omega-5 gliadin sequence showed a clear deletion of the N-terminal sequences which are an important signature of omega-5 gliadin. We also designed specific PCR primers that could identify omega-5 gliadin in the genomic DNA. The results showed that no omega-5 gliadin fragments were detected in the O-free. According to these results, we confirmed that the deficiency of omega-5 gliadin in the O-free is not caused by post-transcriptional or post-translational regulations such as epigenetic phenomena but by a simple deletion in the chromosome. Furthermore, we showed that the low-molecular weight glutenin subunit (LMW-GS) gene in the O-free had a single nucleotide polymorphism (SNP) causing a premature stop codon, resulting in a truncated polypeptide. We expect that the O-free line may serve as an excellent source of wheat that could prevail in the hypo-allergen wheat market, which has recently gained interest world-wide.

The frequency of defective genes in vif and vpr genes in 20 hemophiliacs is associated with Korean Red Ginseng and highly active antiretroviral therapy: the impact of lethal mutations in vif and vpr genes on HIV-1 evolution

  • Cho, Young Keol;Kim, Jung-Eun
    • Journal of Ginseng Research
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    • 제45권1호
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    • pp.149-155
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    • 2021
  • Background: We have reported that internal deletions in the nef, gag, and pol genes in HIV-1-infected patients are induced in those treated with Korean Red Ginseng (KRG). KRG delays the development of resistance mutations to antiretroviral drugs. Methods: The vif-vpr genes over 26 years in 20 hemophiliacs infected with HIV-1 from a single source were sequenced to investigate whether vif-vpr genes were affected by KRG and KRG plus highly active antiretroviral therapy (ART) (hereafter called GCT) and compared the results with our previous data. Results: A significantly higher number of in-frame small deletions were found in the vif-vpr genes of KRG-treated patients than at the baseline, in control patients, and in ART-alone patients (p < 0.001). These were significantly reduced in GCT patients (p < 0.05). In contrast, sequences harboring a premature stop codon (SC) were more significant in GCT patients (10.1%) than in KRG-alone patients, control (p < 0.01), and ART-alone patients (p = 0.078 for peripheral blood mononuclear cells). The proportion of SC in Vpr was similar to that in Vif, whereas the proportion of sequences revealing SC in the env-nef genes was significantly lower than that in the pol-vif-vpr genes (p < 0.01). The genetic distance was 1.8 times higher in the sequences harboring SC than in the sequences without SC (p < 0.001). Q135P in the vif gene is significantly associated with rapid progression to AIDS (p < 0.01). Conclusion: Our data show that KRG might induce sD in the vif-vpr genes and that vif-vpr genes are similarly affected by lethal mutations.

Analysis of Small Fragment Deletions of the APC gene in Chinese Patients with Familial Adenomatous Polyposis, a Precancerous Condition

  • Chen, Qing-Wei;Zhang, Xiao-Mei;Zhou, Jian-Nong;Zhou, Xin;Ma, Guo-Jian;Zhu, Ming;Zhang, Yuan-Ying;Yu, Jun;Feng, Ji-Feng;Chen, Sen-Qing
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권12호
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    • pp.4915-4920
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    • 2015
  • Background: : Familial adenomatous polyposis (FAP) is an autosomal dominant inherited disease mainly caused by mutations of the adenomatous polyposis coli (APC) gene with almost complete penetrance. These colorectal polyps are precancerous lesions that will inevitable develop into colorectal cancer at the median age of 40-year old if total proctocolectomy is not performed. So identification of APC germline mutations has great implications for genetic counseling and management of FAP patients. In this study, we screened APC germline mutations in Chinese FAP patients, in order to find novel mutations and the APC gene germline mutation characteristics of Chinese FAP patients. Materials and Methods: The FAP patients were diagnosed by clinical manifestations, family histories, endoscope and biopsy. Then patients peripheral blood samples were collected, afterwards, genomic DNA was extracted. The mutation analysis of the APC gene was conducted by direct polymerase chain reaction (PCR) sequencing for micromutations and multiplex ligation-dependent probe amplification (MLPA) for large duplications and/or deletions. Results: We found 6 micromutations out of 14 FAP pedigrees, while there were no large duplications and/or deletions found. These germline mutations are c.5432C>T(p. Ser1811Leu), two c.3926_3930delAAAAG (p.Glu1309AspfsX4), c.3921_3924delAAAA (p.Ile1307MetfsX13), c3184_3187delCAAA(p.Gln1061AspfsX59) and c4127_4126delAT (p.Tyr1376LysfsX9), respectively, and all deletion mutations resulted in a premature stop codon. At the same time, we found c.3921_3924delAAAA and two c.3926_3930delAAAAG are located in AAAAG short tandem repeats, c3184_3187delCAAA is located in the CAAA interrupted direct repeats, and c4127_4128 del AT is located in the 5'-CCTGAACA-3', 3'-ACAAGTCC-5 palindromes (inverted repeats) of the APC gene. Furthermore, deletion mutations are mostly located at condon 1309. Conclusions: Though there were no novel mutations found as the pathogenic gene of FAP in this study, we found nucleotide sequence containing short tandem repeats and palindromes (inverted repeats), especially the 5 bp base deletion at codon 1309, are mutations in high incidence area in APC gene,.

성염색체 열성 범저감마글로불린혈증 환자의 임상 소견 및 치료 (Clinical Manifestations and Treatment in Korean Patients with X-Linked Agammaglobulinemia)

  • 조한나;김중곤
    • Pediatric Infection and Vaccine
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    • 제24권3호
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    • pp.152-159
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    • 2017
  • 목적: 본 연구에서는 서울대학교 어린이병원에서 범저감마글로불린혈증(X-linked agammaglobulinemia [XLA])로 진단된 환자들의 임상적 증상 및 치료에 대해서 보고하고자 하였다. 방법: 14명의 남자 환자가 XLA로 진단되었으며 CD19+ B 세포가 2% 미만이며 Bruton's tyrosine kinase (Btk) 유전자 돌연변이가 있는 경우를 기준으로 하였다. 결과: 모든 XLA 환자에서 반복적인 세균성 감염이 있었고 환자의 20%에서 호중구 감소증이 있었으며 환자 어머니의 75%가 보인자였다. Btk gene study에서는 돌연변이가 다양한 부위에서 나타났으며 특정부위에서 집중적으로 발생하지는 않았다. 면역글로불린 정맥주사 후 반복적인 세균성 감염은 줄어들었으나 합병증으로 기관지 확장증이 14명 중 3명, 지속적인 부비동염은 4명에서 발생하였다. 결론: 4세 이전 세균 감염이 반복되는 경우 XLA와 같은 체액성 면역결핍을 의심하여 글로불린 검사를 하는 것이 조기 진단에 중요하며 Btk 유전자변이 검사를 시행하여 확진한 후 면역글로불린 정맥주사 및 예방적 항생제 등 적절한 치료를 통해 합병증을 줄이고 무 질병 상태를 유지할 수 있다.

Coat colour phenotype of Qingyu pig is associated with polymorphisms of melanocortin receptor 1 gene

  • Wu, Xiaoqian;Tan, Zhendong;Shen, Linyuan;Yang, Qiong;Cheng, Xiao;Liao, Kun;Bai, Lin;Shuai, Surong;Li, Mingzhou;Li, Xuewei;Zhang, Shunhua;Zhu, Li
    • Asian-Australasian Journal of Animal Sciences
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    • 제30권7호
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    • pp.938-943
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    • 2017
  • Objective: Qingyu pig, a Chinese indigenous pig breed, exhibits two types of coat colour phenotypes, including pure black and white with black spotting respectively. Melanocortin receptor 1 (MC1R) and agouti signaling protein (ASIP) are two widely reported pivotal genes that significantly affect the regulation of coat colour. The objectives of this study were to investigate whether the polymorphisms of these two genes are associated with coat colour and analyze the molecular mechanism of the coat colour separation in Qingyu pig. Methods: We studied the phenotype segregation and used polymerase chain reaction amplification and Sanger sequencing to investigate the polymorphism of MC1R and ASIP in 121 Qingyu pigs, consisting of 115 black and 6 white with black spotted pigs. Results: Coat colour of Qingyu pig is associated with the polymorphisms of MC1R but not ASIP. We only found 2 haplotypes, $E^{QY}$ and $E^{qy}$, based on the 13 observed mutations from MC1R gene. Among which, $E^{qy}$ presented a recessive inheritance mode in black spotted Qingyu pigs. Further analysis revealed a g.462-463CC insertion that caused a frameshift mutation and a premature stop codon, thus changed the first transmembrane domain completely and lost the remaining six transmembrane domains. Altogether, our results strongly support that the variety of Qingyu pig's coat colour is related to MC1R. Conclusion: Our findings indicated that black coat colour in Qingyu pig was dominant to white with black spotted phenotype and MC1R gene polymorphism was associated with coat colour separation in Qingyu pig.

한국인 쇄골 두개 이형성증 가족에서의 RUNX2 유전자 돌연변이 (A Novel RUNX2 Mutation in a Korean Family with Cleidocranial Dysplasia)

  • 이지원;송지수;신터전;현홍근;김영재;이상훈;김종빈;김정욱
    • 대한소아치과학회지
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    • 제46권4호
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    • pp.409-415
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    • 2019
  • 쇄골 두개 이형성증(Cleidocranial dysplasia)은 상염색체 우성의 유전질환으로, 두개골 간 봉합 지연, 쇄골의 이형성, 과잉치, 영구치 맹출 지연 등을 특징으로 한다. 경조직 형성 조절 인자인 Runt-related transcription factor 2 (RUNX2)의 돌연변이가 쇄골 두개 이형성증을 유발하는 주요 요인으로 보고되고 있다. 이 연구는 치아 맹출 지연이 관찰되는 쇄골 두개 이형성증 가계에서 분자유전학적 원인을 규명하고자 하였다. 23세 여성 환자와 그 어머니를 대상으로 임상 검사 및 방사선 검사를 진행하였고 RUNX2 유전자의 염기 서열을 분석하였다. 대상자 모두에서 3번 exon 내의 단일 염기 결손 돌연변이(NM_001024630.4: c.357delC)를 확인하였다. 이로 인해 frameshift가 발생하여 조기 종결 코돈이 형성될 것으로 예측되며[p.(Asn120Thrfs*24)], 이로 인한 RUNX2 단백질의 기능 손상이 해당 가계에서 나타난 영구치 맹출 지연의 병인이 되었을 것으로 여겨진다.