中华鲟阿黑皮素原cDNA序列克隆及其序列分析  

cDNA CLONE AND SEQUENCE ANALYSIS OF PROOPIOMELANOCORTIN IN CHINESE STURGEON (ACIPENSER SINENSIS)

作　　者：曹宏[1,2] 李创举[3] 危起伟[3] 桂建芳[2] 

机构地区：[1]武汉大学生命科学学院,武汉430072 [2]中国科学院水生生物研究所,淡水生态与生物技术周家重点实验室,武汉430072 [3]中国水产科学院长江水产研究所,武汉430223

出　　处：《水生生物学报》2011年第5期776-782,共7页Acta Hydrobiologica Sinica

基　　金：国家自然科学基金青年科学基金项目(30900139)资助

摘　　要：通过构建中华鲟(Acipenser sinensis)垂体的SMART cDNA质粒文库,首次从文库中筛选得到阿黑皮素原(Proopiomelanocortin,POMC)cDNA全长序列,分别为阿黑皮素原A型基因(Proopiomelanocortin I,AsPOMC-A,EV824935)和阿黑皮素原B型基因(Proopiomelanocortin II,AsPOMC-B,EV825368)。其中,AsPOMC-A和AsPOMC-B分别在文库中出现128次和19次。AsPOMC-A全长1122 bp,有792 bp的开放阅读框,共编码264个氨基酸。AsPOMC-B全长1216 bp,有792 bp的开放阅读框,共编码264个氨基酸。以其氨基酸序列为分子标记,比较了3种鲟鱼的共6种POMC的氨基酸同源性,并利用已报道的鱼类的POMC氨基酸序列构建了系统发育树,可识别2个大的单系类群,即类群I:非新鳍亚纲类群(仅包含辐鳍亚纲的长吻雀鳝),类群II:新鳍亚纲类群。AsPOMC可能是一种进化上更原始的基因。The Chinese sturgeon（Acipenser sinensis） is an endangered national protected species and also an important resource for sturgeon culture industry.However,only a few genes have been identified in this species.We report here the two subtypes of its proopiomelanocortin,POMC from a pituitary cDNA library of a 24 years old female Chinese sturgeon just after its spawning.Among all the 2025 EST clones,the AsPOMC-A and AsPOMC-B appeared 128 and 19 times,respectively.The nucleotide sequences of AsPOMC-A and AsPOMC-B are 1122 and 1216 bp in length,respec-tively,and encode for mature peptides both of 264 aa.The Chinese sturgeon POMC contains the segment corresponding to γ-melanocyte stimulating hormone（γ-MSH）（Y76-S97）,adrenocorticotropic hormone（ACTH）（S140-I178）,γ-lipotropic hormone（γ-LPH）（D181-E209）,β-melanocyte stimulating hormone,（β-MSH）（AsPOMC-A： D212-D228;AsPOMC-B： G212-D228） and β-endorphin（Y231-Q264）,respectively.The phylogenetic tree of POMCs among Chinese sturgeon and other fishes was constructed by neighbour-joining method and maximum parsimony which indicated a divergence of the fish in Neopterygii and other fishes.The Chinese sturgeon POMCs showed greater sequence identity on average with ancient ray-finned fishes including acipenseriformes（89%—99%） and semionotiformes（70%） than with agnathan（31%—33%）,elasmobranchii（40%—45%）,chimaeriformes（33%—36%）,and dipnoi POMCs（57%—63%）.Interest-ingly,Chinese sturgeon POMCs showed obvious variety in sequence identity in teleostean（35%—70%）.Furthermore,we analyzed their phylogenetic significance and suggested that AsPOMC-B might be an ancestral gene,and might play significant roles in reproduction regulation of ancestral fishes.

关 键 词：中华鲟 阿黑皮素原 AsPOMC-A AsPOMC-B 

分 类 号：Q781[生物学—分子生物学]