2012年8月15日 訊 /生物谷BIOON/ --精子游動(dòng),，肺細(xì)胞掃除粘液,，女性輸卵管中的細(xì)胞將卵子從卵巢移動(dòng)到子宮。在這些現(xiàn)象的背后發(fā)揮作用的是鞭毛：纖細(xì)的發(fā)絲狀的結(jié)構(gòu),，是從細(xì)胞表面延伸出來(lái)的,，能夠有節(jié)奏地彎曲、跳動(dòng)或揮動(dòng),。根據(jù)一篇發(fā)表在Developmental Cell期刊上的論文,，來(lái)自葡萄牙古爾班基安科學(xué)研究所(Instituto Gulbenkian de Ciência, IGC)的研究人員仔細(xì)分析了果蠅精細(xì)胞如何構(gòu)建它們的鞭毛。這些發(fā)現(xiàn)為人們進(jìn)一步理解可能觸發(fā)包括不育癥,、呼吸道疾病和腦積水(hydrocephaly)在內(nèi)的一系列與鞭毛運(yùn)動(dòng)缺陷相關(guān)聯(lián)的人類(lèi)疾病的分子和過(guò)程,。
利用電子顯微鏡，Monica Bettencourt-Dias和她的研究小組首次描述了參與果蠅精細(xì)胞中游動(dòng)性鞭毛產(chǎn)生的不同步驟,。研究小組對(duì)一種被稱(chēng)作中心微管對(duì)(central microtubule pair)的關(guān)鍵性蛋白結(jié)構(gòu)如何形成特別感興趣。沒(méi)有這種中心微管對(duì)復(fù)合物,，精細(xì)胞上的鞭毛不能以一種協(xié)作的方式移動(dòng),。
博士后研究員Zita Carvalho-Santos解釋了他們的研究發(fā)現(xiàn)，“我們研究一種特定的果蠅基因Bld10,，發(fā)現(xiàn)這種基因失活的果蠅產(chǎn)生鞭毛不完整的精子,，因此它似乎表明Bld10蛋白是形成中心微管對(duì)所必需的。因此,，發(fā)生突變的精子不能移動(dòng),，雄性果蠅是不育的。人類(lèi)擁有一種類(lèi)似的基因,，它產(chǎn)生一種類(lèi)似的蛋白,，這種蛋白與男性不育癥相關(guān)聯(lián)。”
Monica Bettencourt-Dias補(bǔ)充道,，“我們發(fā)現(xiàn)精子發(fā)生過(guò)程要比我們期待中更加具有動(dòng)態(tài)性：首先第一個(gè)微管鏈形成,，然后第二個(gè)微管鏈形成。我們的研究雖然能夠提供幾個(gè)期待已久的答案,，但是也產(chǎn)生其他的問(wèn)題,，因此研究果蠅精子形成可能解決這些問(wèn)題。”(生物谷Bioon.com)
本文編譯自The ins and outs of building the sperm tail
doi: 10.1016/j.devcel.2012.06.001
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BLD10/CEP135 Is a Microtubule-Associated Protein that Controls the Formation of the Flagellum Central Microtubule Pair
Zita Carvalho-Santos, Pedro Machado, Inês Alvarez-Martins, Susana M. Gouveia, Swadhin C. Jana, Paulo Duarte, Tiago Amado, Pedro Branco, Micael C. Freitas, Sara T.N. Silva, Claude Antony, Tiago M. Bandeiras, Mónica Bettencourt-Dias
Cilia and flagella are involved in a variety of processes and human diseases, including ciliopathies and sterility. Their motility is often controlled by a central microtubule (MT) pair localized within the ciliary MT-based skeleton, the axoneme. We characterized the formation of the motility apparatus in detail in Drosophila spermatogenesis. We show that assembly of the central MT pair starts prior to the meiotic divisions, with nucleation of a singlet MT within the basal body of a small cilium, and that the second MT of the pair only assembles much later, upon flagella formation. BLD10/CEP135, a conserved player in centriole and flagella biogenesis, can bind and stabilize MTs and is required for the early steps of central MT pair formation. This work describes a genetically tractable system to study motile cilia formation and provides an explanation for BLD10/CEP135’s role in assembling highly stable MT-based structures, such as motile axonemes and centrioles.
