7月29日《細(xì)胞》（Cell）雜志上周刊登的一項(xiàng)研究提出了減緩甚至扭轉(zhuǎn)衰老過(guò)程的新可能性。
該研究顯示，動(dòng)物變老是由遺傳學(xué)原因而非組織受損造成的,。科學(xué)家們傳統(tǒng)上認(rèn)為,，老化是細(xì)胞和組織長(zhǎng)期磨損和破裂的必然結(jié)果，毒素,、電離輻射,、疾病和壓力都會(huì)促使動(dòng)物衰老和死亡,。
現(xiàn)在，由斯坦福大學(xué)的斯圖爾特·金帶領(lǐng)的一個(gè)小組,，正在對(duì)微小的線蟲(chóng)展開(kāi)研究,。他們發(fā)現(xiàn)，一種被稱為ELT-3的生物學(xué)開(kāi)關(guān)能夠啟動(dòng)數(shù)百個(gè)涉及老化過(guò)程的基因,，而當(dāng)線蟲(chóng)變老時(shí),，ELT-3變得更加豐富。
科學(xué)家們嘗試人為使這些線蟲(chóng)變老,。他們讓線蟲(chóng)受到熱和輻射等壓力,，但是這些都不能對(duì)涉及老化過(guò)程的基因產(chǎn)生影響。金因此得出結(jié)論：越老的動(dòng)物,，其ELT-3的豐富度越高,，而這是控制機(jī)制出錯(cuò)的結(jié)果。他稱這種現(xiàn)象為“發(fā)育漂變”,。
報(bào)道指出,，如果老化不是化學(xué)過(guò)程造成的災(zāi)難結(jié)果，而是由于控制它的基因發(fā)生了改變,，那么從理論上說(shuō),，在任何水平上，老化速度都可以被減緩甚至停止,。但是金還不能確定,，發(fā)育漂變是否也出現(xiàn)在人類身上。（生物谷Bioon.com）
生物谷推薦原始出處：
Cell,，Vol 134, 291-303,，Yelena V. Budovskaya，Stuart K. Kim
An elt-3/elt-5/elt-6 GATA Transcription Circuit Guides Aging in C. elegans
Yelena V. Budovskaya,1 Kendall Wu,1,3 Lucinda K. Southworth,2 Min Jiang,1 Patricia Tedesco,4 Thomas E. Johnson,4 and Stuart K. Kim1,2,
1 Department of Developmental Biology, Stanford University Medical Center, Stanford, CA 94305, USA
2 Stanford Medical Informatics, Stanford University Medical Center, Stanford, CA 94305, USA
3 Affymetrix, Inc., 3420 Central Expressway, Santa Clara, CA 95051, USA
4 Institute for Behavioral Genetics, Department of Integrative Physiology, University of Colorado, Boulder, Box 447, Boulder, CO 80309, USA
Corresponding author
Stuart K. Kim
[email protected]
Summary
To define the C. elegans aging process at the molecular level, we used DNA microarray experiments to identify a set of 1294 age-regulated genes and found that the GATA transcription factors ELT-3, ELT-5, and ELT-6 are responsible for age regulation of a large fraction of these genes. Expression of elt-5 and elt-6 increases during normal aging, and both of these GATA factors repress expression of elt-3, which shows a corresponding decrease in expression in old worms. elt-3 regulates a large number of downstream genes that change expression in old age, including ugt-9, col-144, and sod-3. elt-5(RNAi) and elt-6(RNAi) worms have extended longevity, indicating that elt-3, elt-5, and elt-6 play an important functional role in the aging process. These results identify a transcriptional circuit that guides the rapid aging process in C. elegans and indicate that this circuit is driven by drift of developmental pathways rather than accumulation of damage.
