14-3-3 is a family of acidic proteins expressing widely in various organs or tissues in all eu-karyotes and acting as an important regulator in a vast array of signaling cascades and metabolic processes by interacting with their targeting proteins .The members in the 14-3-3 family can be subdivided into εgroup and non-εgroup,the majority members in this family even in the model plants Arabidopsis and rice remain to be elucidate.Herein,a full length cDNA of a putative member of the 14-3-3 family,designated as Ca14-3-3a, was isolated from a normalized cDNA library of Capsicum annuum.It is 1 251 bp in length ,harboring an open reading frame of 765 bp in length,encoding a protein with 254 aa in length.Its theoretical molecular mass is 28.7D,its calculated isoelectric point is 4.8,and no signal peptide and transmembrane domain were observed in this putative protein.By homologous alignment analysis ,the putative protein exhibited a 96%and 93%iden-tity with TFT10 of tomato and T14-3g of tobacco in amino acids sequence ,suggesting that it is a protein of 14-3-3 belonging to ε group other than non-εgroup.Especially,the C-terminus sequences of 14-3-3,impor-tant for the interaction of 14-3-3s with SPS,are high similarity between TFT10,T14-3g and Ca14-3-3a.This suggested that Ca14-3-3a is most likely involved in the sucrose metabolism .Real-time PCR showed that the expression of Ca14-3-3a was continuously clined with the time in the Ralstonia solanacearum infected pep-per,it is inferred that it is also involved in the defense reaction of the plant .%14-3-3蛋白是一类在真核生物组织中广泛表达并主要通过与不同的靶蛋白互作参与一系列细胞信号传导和代谢过程的酸性类调控蛋白。通过对辣椒（ Capsicum annuum L．）均一化cDNA文库的筛选，首次分离获得一个辣椒推定蛋白14-3-3的全长cDNA，长度为1251 bp，含有一个长度为765 bp的开放阅读框（ open reading frame，ORF），其推定的蛋白质含有254个氨基酸残基，理论分子量约为28．7 ku，等电点为4．8，无明显信号肽及跨膜区，定名为Ca14-3-3a。序列分析显示Ca14-3-3a属于非ε样14-3-3蛋白，与番茄TFT10及烟草T14-3g的氨基酸序列一致性分别高达96％和93％，尤其是介导14-3-3蛋白与SPS（ Sucrose-6-Phosphate Synthase ）互作的C端序列完全一致，暗示其可能参与辣椒蔗糖代谢。实时定量PCR结果显示Ca14-3-3a基因在辣椒青枯菌处理下表达水平持续下调，推测其还可能通过与不同的靶蛋白结合参与植物病原菌防御应答。
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