广东海洋大学学报
廣東海洋大學學報
엄동해양대학학보
JOURNAL OF GUANGDONG OCEAN UNIVERSITY
2013年
6期
24-29
,共6页
刘连为%陈新军%许强华%王从军%余为
劉連為%陳新軍%許彊華%王從軍%餘為
류련위%진신군%허강화%왕종군%여위
柔鱼%线粒体基因%核核糖体基因%序列分析%分歧时间
柔魚%線粒體基因%覈覈糖體基因%序列分析%分歧時間
유어%선립체기인%핵핵당체기인%서렬분석%분기시간
Ommastrephidae%mitochondria DNA%nuclear ribosomal DNA%sequence analysis%divergence time
为准确检测柔鱼（Ommastrephes bartramii）、茎柔鱼（Dosidicus gigas）与阿根廷滑柔鱼（Illex argentinus）的种间遗传差异，对线粒体16S rRNA、细胞色素b（Cytb）与编码核糖体大亚基的基因（28S rDNA）片段序列进行测定。经比对获得同源片段序列的长度分别为444、430、464 bp，其中16S rRNA与28S rDNA基因片段上分别存在3处和47处碱基插入/缺失。核苷酸组成分析表明：3种柔鱼在3个基因片段上的核苷酸组成差异不显著，在线粒体2个基因片段上的A+T含量（16S rRNA：69.90%、72.01%、74.66%；Cytb：63.61%、68.91%、71.65%）均明显高于G+C含量（16S rRNA：30.10%、27.99%、25.34%；Cytb：36.39%、31.09%、28.35%），而在28S rDNA基因片段上的A+T含量（37.16%、36.74%、38.29%）明显低于G+C含量（62.84%、63.26%、61.71%）。3种柔鱼在28S rDNA基因片段上检测到的核苷酸替代率最低，为6.68%，而蛋白质编码基因Cytb核苷酸替代率最高，为20.93%，核苷酸替代均发生在密码子第3位点上，而且未引起氨基酸替代。基于邻接法、最大简约法与最大似然法重建的系统树显示，柔鱼与茎柔鱼的亲缘关系较近。根据 Cytb 基因片段序列分析，柔鱼与茎柔鱼和阿根廷滑柔鱼的分歧时间分别为653~790万a和765~925万a，种间分化事件发生在中新世至上新世间。
為準確檢測柔魚（Ommastrephes bartramii）、莖柔魚（Dosidicus gigas）與阿根廷滑柔魚（Illex argentinus）的種間遺傳差異，對線粒體16S rRNA、細胞色素b（Cytb）與編碼覈糖體大亞基的基因（28S rDNA）片段序列進行測定。經比對穫得同源片段序列的長度分彆為444、430、464 bp，其中16S rRNA與28S rDNA基因片段上分彆存在3處和47處堿基插入/缺失。覈苷痠組成分析錶明：3種柔魚在3箇基因片段上的覈苷痠組成差異不顯著，在線粒體2箇基因片段上的A+T含量（16S rRNA：69.90%、72.01%、74.66%；Cytb：63.61%、68.91%、71.65%）均明顯高于G+C含量（16S rRNA：30.10%、27.99%、25.34%；Cytb：36.39%、31.09%、28.35%），而在28S rDNA基因片段上的A+T含量（37.16%、36.74%、38.29%）明顯低于G+C含量（62.84%、63.26%、61.71%）。3種柔魚在28S rDNA基因片段上檢測到的覈苷痠替代率最低，為6.68%，而蛋白質編碼基因Cytb覈苷痠替代率最高，為20.93%，覈苷痠替代均髮生在密碼子第3位點上，而且未引起氨基痠替代。基于鄰接法、最大簡約法與最大似然法重建的繫統樹顯示，柔魚與莖柔魚的親緣關繫較近。根據 Cytb 基因片段序列分析，柔魚與莖柔魚和阿根廷滑柔魚的分歧時間分彆為653~790萬a和765~925萬a，種間分化事件髮生在中新世至上新世間。
위준학검측유어（Ommastrephes bartramii）、경유어（Dosidicus gigas）여아근정활유어（Illex argentinus）적충간유전차이，대선립체16S rRNA、세포색소b（Cytb）여편마핵당체대아기적기인（28S rDNA）편단서렬진행측정。경비대획득동원편단서렬적장도분별위444、430、464 bp，기중16S rRNA여28S rDNA기인편단상분별존재3처화47처감기삽입/결실。핵감산조성분석표명：3충유어재3개기인편단상적핵감산조성차이불현저，재선립체2개기인편단상적A+T함량（16S rRNA：69.90%、72.01%、74.66%；Cytb：63.61%、68.91%、71.65%）균명현고우G+C함량（16S rRNA：30.10%、27.99%、25.34%；Cytb：36.39%、31.09%、28.35%），이재28S rDNA기인편단상적A+T함량（37.16%、36.74%、38.29%）명현저우G+C함량（62.84%、63.26%、61.71%）。3충유어재28S rDNA기인편단상검측도적핵감산체대솔최저，위6.68%，이단백질편마기인Cytb핵감산체대솔최고，위20.93%，핵감산체대균발생재밀마자제3위점상，이차미인기안기산체대。기우린접법、최대간약법여최대사연법중건적계통수현시，유어여경유어적친연관계교근。근거 Cytb 기인편단서렬분석，유어여경유어화아근정활유어적분기시간분별위653~790만a화765~925만a，충간분화사건발생재중신세지상신세간。
Ommastrephes bartramii, Dosidicus gigas and Illex argentinus are major fishing objects for China pelagic squid fishing industry. To evaluate the genetic variance of the three species, partial sequence of 16S rRNA, Cytb and 28S rDNA genes were amplified and sequenced. Three homologous fragments of 444 bp for 16S rRNA, 430 bp for Cytb and 464 bp for 28S rDNA genes were obtained by sequences aligning, and 3 and 47 insert-delete (indel) loci were found in the 16S rRNA and 28S rDNA gene fragments respectively. Result of nucleotide composition analysis indicated that no signal difference was detected in three gene fragments, and the AT content (16S rRNA: 69.90%, 72.01%, 74.66%;Cytb:63.61%, 68.91%, 71.65%) was much higher than GC content (16S rRNA:30.10%, 27.99%, 25.34%;Cytb:36.39%, 31.09%, 28.35%) in two mitochondria DNA fragments. On the contrary, it has much lower AT content (37.16%, 36.74%, 38.29%) than GC content (62.84%, 63.26%, 61.71%) in 28S rDNA gene fragment whose nucleotide substitution rate was 6.68% in contrast to 20.93%in the protein coding gene of Cytb. All the nucleotide substitutions in Cytb gene fragment were occurred at the third codon positions without amino acid substitutions. Neighbor-Joining, Maximum-Parsimony and Maximum-likelihood phylogenetic trees all showed that the relationship between O. bartramii and D. gigas was closer. Based on sequence analysis of partial Cytb gene, the estimated divergence time between O. bartramii and D. gigas was 6.53-7.90 million years ago, while it was 7.65-9.25 million years ago between O. bartramii and I. argentinus, which might had occurred between Micene and Pliocene.
