Institute for Behavioral Genetics, University of Colorado, Boulder, CO 80303, USA.
J Gerontol A Biol Sci Med Sci. 2011 Aug;66(8):842-54. doi: 10.1093/gerona/glr089. Epub 2011 May 28.
The large post-reproductive life span reported for the free-living hermaphroditic nematode, Caenorhabditis elegans, which lives for about 10 days after its 5-day period of self-reproduction, seems at odds with evolutionary theory. Species with long post-reproductive life spans such as mammals are sometimes explained by a need for parental care or transfer of information. This does not seem a suitable explanation for C elegans. Previous reports have shown that C elegans can regain fertility when mated after the self-fertile period but did not report the functional limits. Here, we report the functional life span of the C elegans germ line when mating with males. We show that C elegans can regain fertility late in life (significantly later than in previous reports) and that the end of this period corresponds quite well to its 3-week total life span. Genetic analysis reveals that late-life fertility is controlled by conserved pathways involved with aging and dietary restriction.
自由生活的雌雄同体线虫秀丽隐杆线虫在完成 5 天的自我繁殖后,还能再存活约 10 天,这一现象与进化理论似乎相悖。有些物种,如哺乳动物,其繁殖后期的寿命较长,这有时可以用需要亲代照顾或信息传递来解释。但这似乎并不是秀丽隐杆线虫的合适解释。先前的报告表明,秀丽隐杆线虫在完成自我繁殖后与雄性交配可以恢复生育能力,但没有报告其功能极限。在这里,我们报告了秀丽隐杆线虫与雄性交配时生殖系的功能寿命。我们发现,秀丽隐杆线虫在生命后期(比以前的报告晚得多)可以恢复生育能力,而这个时期的结束与它的 3 周总寿命相当吻合。遗传分析表明,晚期生育能力受与衰老和饮食限制有关的保守途径控制。