Burk N E, Messer L A, Ernst C W, Rothschild M F
Department of Animal Science, Iowa State University, Ames 50011, USA.
Anim Biotechnol. 1998;9(2):155-60. doi: 10.1080/10495399809525902.
To date, gene identification in elephants has essentially related to evolutionary studies. Further identification of genes in elephants could provide additional information for evolutionary studies and for evaluating genetic diversity in existing elephant populations. The objective of this project was to identify sequence tagged sites (STSs) in the Asian and the African elephant for the following genes: melatonin receptor 1a (MTNR1A), retinoic acid receptor beta (RARB), and leptin receptor (LEPR). These genes are highly conserved among mammals, and all may play a role in reproduction. Heterologous primers for PCR were designed from sequences available in other species. Fragments of size 141 base pairs (bp) for RARB and 327 bp for LEPR were obtained by amplifying genomic Asian and African elephant DNA. The LEPR fragment included an intron of 164 bp. Also, a 417 bp fragment for MTNR1A was obtained in the Asian elephant only. All PCR products were sequenced and comparison computations were made at the nucleotide and amino acid levels to sequence available in the GenBank database. Nucleotide sequence for RARB was identical for both Asian and African elephants and differed by only 3 bp for LEPR. Deduced amino acid sequence was identical for both STSs in both species. Elephants were relatively similar in comparison to other mammals and less similar to chickens.
迄今为止，大象基因的鉴定主要与进化研究相关。进一步鉴定大象的基因可为进化研究以及评估现有大象种群的遗传多样性提供更多信息。本项目的目的是鉴定亚洲象和非洲象中以下基因的序列标签位点（STS）：褪黑素受体1a（MTNR1A）、视黄酸受体β（RARB）和瘦素受体（LEPR）。这些基因在哺乳动物中高度保守，且都可能在生殖过程中发挥作用。用于PCR的异源引物是根据其他物种中可用的序列设计的。通过扩增亚洲象和非洲象的基因组DNA，获得了大小为141个碱基对（bp）的RARB片段和327 bp的LEPR片段。LEPR片段包含一个164 bp的内含子。此外，仅在亚洲象中获得了一个417 bp的MTNR1A片段。对所有PCR产物进行测序，并在核苷酸和氨基酸水平上与GenBank数据库中可用的序列进行比较计算。亚洲象和非洲象的RARB核苷酸序列相同，LEPR仅相差3 bp。两个物种中这两个STS的推导氨基酸序列相同。与其他哺乳动物相比，大象相对相似，与鸡的相似性较低。
