摘要
【目的】明确镞果实蝇亚属(Zeugodacus)6种实蝇的形态、线粒体全基因组基本结构特征,果实蝇的系统发育和亲缘关系。【方法】采用形态描述和特征图片相结合比较方法,基于高通量测序、测定分析线粒体全基因组,使用DNA MAN软件、AT偏移率(AT skew)=(A–T)/(A+T)和GC偏移率(GC skew )=(G–C)/(G+C)计算线粒体全基因组碱基含量、偏移率,基于最大似然法(maximum likelihood, ML)构建系统发育树。【结果】探明了镞果实蝇6种实蝇头、胸、腹的主要形态特征及区别。头:颜带实蝇具2条黑色横带,异端黑实蝇具1条黑色宽横带,其余4种均具2个颜斑;胸部:瓜实蝇、异狭腹实蝇前缘带过R_(2+3),不达R_(4+5),翅端扩大,中肘横脉(dm-cu横脉)具褐色带;异端黑实蝇前缘带窄,稍过R_(2+3),全长几近等宽;颜带实蝇、黑漆实蝇、越南实蝇前缘带窄,达R_(2+3)端部;腹:颜带实蝇腹部黑色,其余5种腹部均为黄褐色具黑斑。线粒体全基因序列总长度为15 835~15 919bp,均包含13个蛋白质编码基因(protein-coding gene, PCGs)、22个tRNA基因、2个rRNA基因和1个非编码控制区,共37个典型线粒体基因。6种实蝇线粒体全基因组序列中A、 C、 G、 T的含量分别为38.3%~39.7%、15.9%~16.5%、9.8%~10.5%和34.3%~34.8%,A+T含量为72.9%~74.0%,存在AT偏好性;6种果实蝇的线粒体全基因组的AT Skew为0.051~0.074,均为正值;GC Skew为-0.252~-0.210,均为负值,全基因组核苷酸含量顺序为A>T>C>G;6种实蝇在蛋白质所有氨基酸的密码子中亮氨酸Leu(L)使用频率N及相对密码子使用频率(relative synonymous codon usage, RSCU)均最高,N为600~611、RSCU为15.98~16.69,占总氨基酸含量的33.1%~39.66%。通过对6种实蝇与其近缘种线粒体基因组的系统发育分析,6种实蝇均稳定地嵌入镞果实蝇亚属分支之中,确立了其归属于镞果实蝇亚属的分类地位和亲缘种关系。【结论】确定了6种实蝇的主要形态特征,测定和登录基因库(GenBank),揭示线粒体全基因组的基本结构,确定了6种实蝇的分类地位和亲缘关系,为果实蝇物种分类鉴定、分子标记和系统发育研究等提供参考依据。
【Objective】Morphological characteristics,complete mitochondrial genomes,and phylogenetic relationships of 6 important species in the subgenera of Bactrocera and Zeugodacus were studied.【Methods】A phylogenetic tree was constructed using the maximum likelihood(ML)method with an approach that compared 6 species in the subgenus of fruit flies using the combination of morphological description,characteristic images,and complete mitochondrial genome determined based on high-throughput sequencing.DNA MAN was employed along with formulas AT skew=(A-T)/(A+T)and GC skew=(G-C)/(G+C)to calculate the base content and skew rate of the complete mitochondrial genome.【Results】The major differential morphology on the head,thorax,and abdomen of the 6 species included the following.(A)Having two black transverse bands on B.cilifer,one broad band on B.maculaus,and two facial spots on the other 4 species on the head.(B)The costal band of B.cucurbitae and B.synnephes extended beyond vein R_(2+3) but not to R_(4+5),which expanded at the wing apex with a brown band on the dm-cu crossvein on the thorax.By contrast,the costal band of B.maculaus was narrow that extended slightly beyond R_(2+3) and remained nearly uniform in width throughout.For B.cilifer,B.scutellaris,and B.yoshimotoi,the costal band was narrow and terminated at R_(2+3).And(C)B.cilifer had an entirely black abdomen,whereas the other 5 species had a yellowish-brown abdomen with black maculae.The length of mitochondrial genome of the 6 species ranged from 15835 to 15919 base pairs(bp)that contained 37 typical mitochondrial genes that included 13 protein-coding genes(PCGs),22 transfer RNA(tRNA)genes,2 ribosomal RNA(rRNA)genes,and 1 non-coding control region.The nucleotides in the mitochondrial genomes were adenine(A),cytosine(C),guanine(G),and thymine(T)in the contents of 38.3%~39.7%,15.9%~16.5%,9.8%~10.5%,and 34.3%~34.8%,respectively.The combined A+T content reached 72.9%~74.0%,indicating a significant AT bias.The positive AT skew ranged 0.051~0.074,while the negative GC skew ranged from-0.252 to-0.210.The nucleotide contents in the entire genome were consistently A>T>C>G.The codon usage analysis showed that leucine(L)was the highest usage frequency(N)amino acid.The N value ranged 600~611,the relative synonymous codon usage(RSCU)value ranged 15.98~16.69,and L accounted for 33.1%~39.66%of the total amino acid.A phylogenetic analysis based on the mitochondrial genome data indicated that all 6 species were stably clustered within the Zeugodacus subgenus clade,which clarified the taxonomic affiliation within the subgenus and the phylogenetic relationships with closely related species.【Conclusion】Major morphological characteristics of the 6 fruit fly species were examined with the genes determined and the sequences deposited in GenBank,and the basic structure of the complete mitochondrial genome unveiled.Additionally,the taxonomy and phylogenetic relationships of the 6 species were clarified to provide a basis for species identification,molecular marker development,and phylogenetic research on fruit flies.
作者
黄振
余慧
白永华
郭琼霞
HUANG Zhen;YU Hui;BAI Yonghua;GUO Qiongxia(Fuzhou Changle Airport Customs,Fuzhou,Fujian 350209,China;Shanghai Municipal Agro-tech Extension and Service Centre,Shanghai 201103,China;Mengla Customs Comprehensive Technology Center,Xishuangbanna,Yunan 666300,China;Fuzhou Customs Technology Center,Fuzhou,Fujian 350001,China)
出处
《福建农业学报》
北大核心
2026年第1期105-117,共13页
Fujian Journal of Agricultural Sciences
基金
福建省自然科学基金项目(2011J01066、2012JO1061)
福州海关科研项目(fk2022-09)。
关键词
颜带实蝇
形态特征
线粒体全基因组
系统发育
亲缘关系
Bactrocera cilifer
morphological characteristics
complete mitochondrial genome
phylogeny
genetic relationship
