來(lái)自澳大利亞,、美國(guó)、日本,、英國(guó)和德國(guó)的科學(xué)家已完成塔馬爾沙袋鼠的基因序列測(cè)定工作,，最新研究成果報(bào)告刊載于《基因組生物學(xué)》（Genome Biology ）雜志。
英國(guó)《每日電訊報(bào)》8月20日援引研究報(bào)告報(bào)道,，研究人員在塔馬爾沙袋鼠基因序列中發(fā)現(xiàn)一組基因,，名為HOX。正是這一組基因使袋鼠擁有異常強(qiáng)壯的后肢,，從而演化出極具特色的移動(dòng)方式,。
其實(shí)，有袋動(dòng)物和包括人類(lèi)在內(nèi)的有胎盤(pán)動(dòng)物大約在1.8億年前“是一家”,，由同一個(gè)哺乳動(dòng)物祖先分化進(jìn)化而來(lái),。而塔馬爾沙袋鼠是第三種接受基因序列測(cè)定的有袋動(dòng)物。
一些研究人員說(shuō),，這次測(cè)序工作有利于了解整個(gè)哺乳動(dòng)物的進(jìn)化史,。
“觀察一種與眾不同的有機(jī)體是有價(jià)值的，可以了解人類(lèi)和其他哺乳動(dòng)物的進(jìn)化過(guò)程,，”有袋動(dòng)物專(zhuān)家伊麗莎白·默奇森說(shuō)：“借助觀察在早期分化進(jìn)化的哺乳動(dòng)物,，例如袋鼠，可以給你一個(gè)看待哺乳動(dòng)物進(jìn)化的新視角,。”(生物谷 Bioon.com)
doi:10.1186/gb-2011-12-8-r81
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Genome sequence of an Australian kangaroo, Macropus eugenii, provides insight into the evolution of mammalian reproduction and development
Marilyn B Renfree, Anthony T Papenfuss, Janine E Deakin, James Lindsay, Thomas Heider, Katherine Belov, Willem Rens, Paul D Waters, Elizabeth A Pharo, Geoff Shaw, Emily SW Wong, Christophe M Lefevre, Kevin R Nicholas, Yoko Kuroki, Matthew J Wakefield, Kyall R Zenger, Chenwei Wang, Malcolm Ferguson-Smith, Frank W Nicholas, Danielle Hickford, Hongshi Yu, Kirsty R Short, Hannah V Siddle, Stephen R Frankenberg, Keng Yih Chew, Brandon R Menzies, Jessica M Stringer, Shunsuke Suzuki, Timothy A Hore, Ma
Background We present the genome sequence of the tammar wallaby, Macropus eugenii, which is a member of the kangaroo family and the first representative of the iconic hopping mammals that symbolize Australia to be sequenced. The tammar has many unusual biological characteristics, including the longest period of embryonic diapause of any mammal, extremely synchronized seasonal breeding and prolonged and sophisticated lactation within a well-defined pouch. Like other marsupials, it gives birth to highly altricial young, and has a small number of very large chromosomes, making it a valuable model for genomics, reproduction and development. Results The genome has been sequenced to 2x coverage using Sanger sequencing, enhanced with additional next generation sequencing and the integration of extensive physical and linkage maps to build the genome assembly. We also sequenced the tammar transcriptome across many tissues and developmental time points. Our analyses of these data shed light on mammalian reproduction, development and genome evolution: there is innovation in reproductive and lactational genes, rapid evolution of germ cell genes, and incomplete, locus-specific X inactivation. We also observe novel retrotransposons and a highly rearranged major histocompatibility complex, with many class I genes located outside the complex. Novel microRNAs in the tammar HOX clusters uncover new potential mammalian HOX regulatory elements. Conclusions Analyses of these resources enhance our understanding of marsupial gene evolution, identify marsupial-specific conserved non-coding elements and critical genes across a range of biological systems, including reproduction, development and immunity, and provide new insight into marsupial and mammalian biology and genome evolution.
