生物谷報(bào)道:時(shí)序和其它生理節(jié)奏內(nèi)在周期性控制著人體蘇醒與睡眠的循環(huán)生物鐘,,科學(xué)家們認(rèn)為這種生理周期性也許已經(jīng)進(jìn)化到了能預(yù)見環(huán)境內(nèi)的調(diào)控性短暫變化,但是有關(guān)生理周期性的兩個(gè)方面:24小時(shí)的日夜周期以及每年季節(jié)變化的周期之間的關(guān)系,,目前了解的并不太多,。
在本期的Science(6月29日)雜志上,兩個(gè)研究小組獲得了突破性的發(fā)現(xiàn):他們發(fā)現(xiàn)果蠅的一種變異能幫助這種果蠅進(jìn)入一個(gè)名為“滯育”的類似冬眠的生長(zhǎng)停止?fàn)顟B(tài),,這一發(fā)現(xiàn)連接了生理周期性的日夜周期和季節(jié)變化的周期,。
在第一篇文章中,來(lái)自英國(guó)的萊斯特大學(xué)(University of Leicester)遺傳學(xué)和生物學(xué)系的研究人員發(fā)現(xiàn)黑腹果蠅中有一個(gè)生理節(jié)律基因變異:timeless,,攜帶這一變異的果蠅比野生型果蠅能更好地響應(yīng)環(huán)境的變化,。
通過進(jìn)一步的將timeless基因引入不同的遺傳背景,,研究人員還發(fā)現(xiàn)timeless基因天然的和人工的等位基因都會(huì)影響果蠅對(duì)外部光度和溫度作出反應(yīng)。這一變異通過自然選擇傳遍了歐洲,,這種變化改變了一個(gè)重要的生活史,,從而也許增加了果蠅對(duì)季節(jié)條件變化的適應(yīng)能力。
英文原文:
Science 29 June 2007:
Vol. 316. no. 5833, pp. 1895 - 1898
DOI: 10.1126/science.1138412
Natural Selection Favors a Newly Derived timeless Allele in Drosophila melanogaster
Eran Tauber,1* Mauro Zordan,2* Federica Sandrelli,2* Mirko Pegoraro,1,2 Nicolò Osterwalder,2 Carlo Breda,1,2 Andrea Daga,2 Alessandro Selmin,1,2 Karen Monger,1 Clara Benna,2 Ezio Rosato,1 Charalambos P. Kyriacou,1 Rodolfo Costa2
Circadian and other natural clock-like endogenous rhythms may have evolved to anticipate regular temporal changes in the environment. We report that a mutation in the circadian clock gene timeless in Drosophila melanogaster has arisen and spread by natural selection relatively recently in Europe. We found that, when introduced into different genetic backgrounds, natural and artificial alleles of the timeless gene affect the incidence of diapause in response to changes in light and temperature. The natural mutant allele alters an important life history trait that may enhance the fly's adaptation to seasonal conditions.
1 Department of Genetics, University of Leicester, Leicester LE1 7RH, UK.
2 Department of Biology, University of Padova, 35131 Padova, Italy.
* These authors contributed equally to this work.
Present address: Department of Pharmacology, University of Padova, Largo Meneghetti 2, 35131 Padova, Italy.
To whom correspondence should be addressed. E-mail: [email protected]
在第二篇文章中,,來(lái)自意大利帕多瓦大學(xué)(University of Padova),,英國(guó)萊斯特大學(xué)(University of Leicester),德國(guó)雷根斯堡大學(xué)(University of Regensburg)的研究人員在上一個(gè)研究的基礎(chǔ)上進(jìn)行了延伸研究,,發(fā)現(xiàn)這一變異導(dǎo)致身體時(shí)鐘機(jī)制中更穩(wěn)定的蛋白質(zhì)-蛋白質(zhì)相互作用,。