Banks M A, Hedgecock D, Waters C
Bodega Marine Laboratory, University of Califorńia at Davis, Bodega Bay 94923.
Mol Mar Biol Biotechnol. 1993 Jun;2(3):129-36.
Mitochondrial DNA sequence variation was characterized for the large subunit rRNA-coding gene (16SrDNA) in two closely related Pacific oyster species (Crassostrea gigas and C. sikamea) and an out group, the Olympia oyster (Ostrea lurida). Although each species was shown to have a single, fixed haplotype for the DNA sequence under study, 7 nucleotide differences were found between C. gigas and C. sikamea, and these two species differed from the O. lurida haplotype at 62 and 60 nucleotide sites, respectively. Nucleotide differences for the two Crassostrea species showed a notable transition bias (85.7%) in contrast to the marginal transversion bias (54.5%) in nucleotide differences between Crassostrea haplotypes and the more distantly related O. lurida. Conservation of primary sequence in all three oyster species as well as other published 16SrDNA sequences was noted for regions with apparent functional significance. We developed DNA sequence-specific discrimination techniques and employed sequence-specific PCR primers, dot-blot hybridization, and restriction digests as alternate techniques for rapid diagnosis of Crassostrea oyster larvae.
对两个亲缘关系密切的太平洋牡蛎物种（太平洋牡蛎和西氏巨牡蛎）以及一个外类群奥林匹亚牡蛎（奥林匹亚牡蛎）的大亚基核糖体RNA编码基因（16S rDNA）的线粒体DNA序列变异进行了表征。尽管在所研究的DNA序列中，每个物种都显示有一个单一的、固定的单倍型，但在太平洋牡蛎和西氏巨牡蛎之间发现了7个核苷酸差异，这两个物种分别在62个和60个核苷酸位点上与奥林匹亚牡蛎的单倍型不同。与太平洋牡蛎单倍型和亲缘关系更远的奥林匹亚牡蛎之间核苷酸差异的轻微颠换偏向（54.5%）相比，这两种太平洋牡蛎物种的核苷酸差异显示出明显的转换偏向（85.7%）。在所有三种牡蛎物种以及其他已发表的16S rDNA序列中，在具有明显功能意义的区域注意到了一级序列的保守性。我们开发了DNA序列特异性鉴别技术，并采用序列特异性PCR引物、斑点杂交和限制性消化作为快速诊断太平洋牡蛎幼虫的替代技术。
