遗传学报
遺傳學報
유전학보
ACTA GENETICA SINICA
2007年
6期
486-490
,共5页
宋莉%王玉瑶%柴宝峰%王伟%梁爱华
宋莉%王玉瑤%柴寶峰%王偉%樑愛華
송리%왕옥요%시보봉%왕위%량애화
八肋游仆虫%肽链释放因子3%表达%Pull-down分析
八肋遊僕蟲%肽鏈釋放因子3%錶達%Pull-down分析
팔륵유부충%태련석방인자3%표체%Pull-down분석
Euplotes octocarinatus%polypeptide release factor 3%expression%pull-down assay
以八肋游仆虫第二类肽链释放因子eRF3基因为模板,用PCR的方法获得eRF3的C端(eRF3C)和C端缺失76个氨基酸的突变体eRF3Ct片段,并构建重组表达质粒pGEX-6p-1-eRF3C和pGEX-6p-1-eRF3Ct,转入大肠杆菌BL21(DE3)中获得了可溶性表达.通过Glutathione Sepharose 4B柱亲和层析纯化,重组蛋白GST-eRF3C和GST-eRF3Ct获得纯化.Western blotting分析表明获得的蛋白为目的蛋白.PreScission酶切割后得到eRF3C和eRF3Ct蛋白.体外pull down分析显示eRF3C和eRF3Ct均能与八肋游仆虫第一类释放因子eRF1a相互作用,这表明八肋游仆虫eRF3 C端的76个氨基酸对于释放因子eRF1a的结合不是必需的.
以八肋遊僕蟲第二類肽鏈釋放因子eRF3基因為模闆,用PCR的方法穫得eRF3的C耑(eRF3C)和C耑缺失76箇氨基痠的突變體eRF3Ct片段,併構建重組錶達質粒pGEX-6p-1-eRF3C和pGEX-6p-1-eRF3Ct,轉入大腸桿菌BL21(DE3)中穫得瞭可溶性錶達.通過Glutathione Sepharose 4B柱親和層析純化,重組蛋白GST-eRF3C和GST-eRF3Ct穫得純化.Western blotting分析錶明穫得的蛋白為目的蛋白.PreScission酶切割後得到eRF3C和eRF3Ct蛋白.體外pull down分析顯示eRF3C和eRF3Ct均能與八肋遊僕蟲第一類釋放因子eRF1a相互作用,這錶明八肋遊僕蟲eRF3 C耑的76箇氨基痠對于釋放因子eRF1a的結閤不是必需的.
이팔륵유부충제이류태련석방인자eRF3기인위모판,용PCR적방법획득eRF3적C단(eRF3C)화C단결실76개안기산적돌변체eRF3Ct편단,병구건중조표체질립pGEX-6p-1-eRF3C화pGEX-6p-1-eRF3Ct,전입대장간균BL21(DE3)중획득료가용성표체.통과Glutathione Sepharose 4B주친화층석순화,중조단백GST-eRF3C화GST-eRF3Ct획득순화.Western blotting분석표명획득적단백위목적단백.PreScission매절할후득도eRF3C화eRF3Ct단백.체외pull down분석현시eRF3C화eRF3Ct균능여팔륵유부충제일류석방인자eRF1a상호작용,저표명팔륵유부충eRF3 C단적76개안기산대우석방인자eRF1a적결합불시필수적.
Termination of translation in eukaryotes requires two polypeptide chain-release factors, eRF1 and eRF3. eRF1 recognizes stop signals, whereas eRF3 is a ribosome-dependent and eRFl-dependent GTPase. Polypeptide release factor eRF3 consists of N-terminal variable region and C-terminal conserved part. C-terminal part of eRF3 is responsible for termination of the translation.In the present study, the C-terminal of Euplotes octocarinatus eRF3 (eRF3C) and truncate eRF3C lacking 76 amino acids in C-terminal (eRF3Ct) were expressed in Escherichia coli. The recombinant GST-eRF3C and GST-eRF3Ct polypeptides were purified by affinity chromatography using glutathione Sepharose 4B column. After enzymatic cleavage of GST tail, the eRF3C and eRF3Ct protein were obtained. Pull-down analysis showed that the recombinant GST-eRF3C and GST-eRF3Ct polypeptides interacted with E. octocarinatus polypeptide chain release factor eRF1a. This result suggested that the C-terminal of eRF3 having 76amino acids were not required for the binding of eRFla in Euplotes octocarinatus.