在內(nèi)布拉斯加的Sand Hill,，那里的鹿鼠（deer mice）已經(jīng)通過(guò)生長(zhǎng)出類似的淺色毛皮而適應(yīng)了它們的多塵且色淺的周圍環(huán)境。
資料來(lái)源: Emily Kay
據(jù)8月28日的《科學(xué)》雜志報(bào)道說(shuō),，在內(nèi)布拉斯加的Sand Hill,，那里的鹿鼠（deer mice）已經(jīng)通過(guò)生長(zhǎng)出類似的淺色毛皮而適應(yīng)了它們的多塵且色淺的周圍環(huán)境 – 據(jù)科研人員披露，這種特征來(lái)自某一基因突變,，而該突變?cè)赟and Hills形成之前尚未在該鼠中出現(xiàn),。 這一發(fā)現(xiàn)清楚地證明了，一種生物對(duì)某一新環(huán)境的快速適應(yīng)并不總是依賴于在它們?nèi)后w中的現(xiàn)有的基因變異,，而是可能牽涉到包括遺傳學(xué),、發(fā)育學(xué)和進(jìn)化學(xué)在內(nèi)的所有機(jī)制。
Catherine Linnen及其同僚對(duì)美國(guó)中西部的這些Sand Hills上的鹿鼠進(jìn)行了研究,，并將它們與附近的生活在土壤顏色較深地帶的長(zhǎng)著較深色毛皮的鹿鼠種群進(jìn)行了對(duì)比,。 研究人員在淺色鹿鼠中發(fā)現(xiàn)了一種以前不知道的毛皮顏色的模式，并發(fā)現(xiàn)它與某個(gè)特別基因（即Agouti基因）的突變有關(guān),。人們已知該基因?qū)Q定毛皮顏色起著作用,。 他們提示，這種Agouti的顏色變化的突變與該基因中的一個(gè)單一氨基酸的缺失有關(guān)聯(lián)（或是由其直接造成的）- 這種突變對(duì)Sand Hills上的鹿鼠帶來(lái)了裨益,。（生物谷Bioon.com）
生物谷推薦原始出處：
Science 28 August 2009:DOI: 10.1126/science.1175826
On the Origin and Spread of an Adaptive Allele in Deer Mice
Catherine R. Linnen,1,* Evan P. Kingsley,1 Jeffrey D. Jensen,2 Hopi E. Hoekstra1
Adaptation is a central focus of biology, although it can be difficult to identify both the strength and agent of selection and the underlying molecular mechanisms causing change. We studied cryptically colored deer mice living on the Nebraska Sand Hills and show that their light coloration stems from a novel banding pattern on individual hairs produced by an increase in Agouti expression caused by a cis-acting mutation (or mutations), which either is or is closely linked to a single amino acid deletion in Agouti that appears to be under selection. Furthermore, our data suggest that this derived Agouti allele arose de novo after the formation of the Sand Hills. These findings reveal one means by which genetic, developmental, and evolutionary mechanisms can drive rapid adaptation under ecological pressure.
1 Department of Organismic and Evolutionary Biology and the Museum of Comparative Zoology, Harvard University, 26 Oxford Street, Cambridge, MA 02138, USA.
2 Center for Theoretical Evolutionary Genomics, Department of Integrative Biology, University of California, Berkeley, 3060 Valley Life Sciences Building, Berkeley, CA 94720, USA.
