依據(jù)以往的認識,,不同物種交配即使生產(chǎn),,下一代也沒辦法繼續(xù)繁殖,。臺灣“中研院”呂俊毅博士團隊透過觀察酵母菌“種化”基因,,解開了不同物種之間交配卻無法繁殖的進化密碼,。
“種”是生物分類最基本的單位,早在八十年前,,就有進化大師提出假說,,可能是特定基因不兼容的關(guān)系,造成不同物種之間的個體,,即使交配,,生出來的下一代,也不具有繁殖能力。
多年來,,全球?qū)W者都試圖找出這個無法演化的基因密碼,。臺灣“中研院”呂俊毅博士團隊利用大量、快速繁殖的酵母菌,,清楚完整地呈現(xiàn)出“種化”機制,,其中關(guān)鍵就是跟細胞內(nèi)的粒線體功能有關(guān)。
臺“中研院”分子生物研究所助研究員呂俊毅博士說:“在我們研究中發(fā)現(xiàn)類似的現(xiàn)象,,就是他們的粒線體之所以不一樣,,是因為它們使用能源方式不一樣,很顯然有一個物種像是柴油引擎,,另一個像是汽油引擎,,所以說把兩個引擎互換的時候,當然就會發(fā)現(xiàn)兩個功率完全變的不一樣,。”
研究顯示,,“種化”的問題關(guān)鍵在于細胞內(nèi)的粒線體與細胞核不兼容,粒線體可能在演化上,,為了適應(yīng)不同營養(yǎng)環(huán)境,,偏向不同的代謝方式,導(dǎo)致了兩個種的分離,。
研究成果對于未來進化研究邁進一大步,,受到國際高度矚目,在生物學(xué)術(shù)界最頂尖期刊《細胞》(Cell)上發(fā)表,。這項成果對于未來醫(yī)學(xué)應(yīng)用有也幫助,,可以持續(xù)觀察粒線體扮演的角色,為癌癥與老化方面的研究提供參考,。(生物谷Bioon.com)
生物谷推薦原始出處:
Cell,,Volume 135, Issue 6, 1065-1073,Hsin-Yi Lee,,Jun-Yi Leu
Incompatibility of Nuclear and Mitochondrial Genomes Causes Hybrid Sterility between Two Yeast Species
Hsin-Yi Lee1,3,Jui-Yu Chou1,2,3,Liplee Cheong1,Nai-Hsin Chang1,Shi-Yow Yang1andJun-Yi Leu1,,
1 Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
2 Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei, Taiwan
3 These authors contributed equally to this work
Hybrids between species are usually unviable or sterile. One possible mechanism causing reproductive isolation is incompatibility between genes from different species. These 'speciation'genes are interacting components that cannot function properly when mixed with alleles from other species. To test whether such genes exist in two closely related yeast species, we constructed hybrid lines in which one or two chromosomes were derived from Saccharomyces bayanus, and the rest were from Saccharomyces cerevisiae. We found that the hybrid line with Chromosome 13 substitution was completely sterile and identified Aep2, a mitochondrial protein encoded on Chromosome 13, to cause the sporulation defect as S. bayanus AEP2 is incompatible with S. cerevisiae mitochondria. This is caused by the inability of S. bayanus Aep2 protein to regulate the translation of the S. cerevisiae OLI1 mRNA. We speculate that AEP2and OLI1 have evolved during the adaptation of S. bayanus to nonfermentable carbon sources, thereby driving speciation.