Ballen Cissy, Healey Mo, Wilson Mark, Tobler Michael, Olsson Mats
School of Biological Sciences, University of Sydney, Camperdown, Sydney, Australia.
Naturwissenschaften. 2012 Aug;99(8):661-4. doi: 10.1007/s00114-012-0941-1. Epub 2012 Jul 8.
Telomeres shorten as a consequence of DNA replication, in particular in cells with low production of telomerase and perhaps in response to physiological stress from exposure to reactive oxygen species, such as superoxide. This process of telomere attrition is countered by innate antioxidation, such as via the production of superoxide dismutase. We studied the inheritance of telomere length in the Australian painted dragon lizard (Ctenophorus pictus) and the extent to which telomere length covaries with mass-corrected maternal reproductive investment, which reflects the level of circulating yolk precursor and antioxidant, vitellogenin. Our predictors of offspring telomere length explained 72 % of telomere variation (including interstitial telomeres if such are present). Maternal telomere length and reproductive investment were positively influencing offspring telomere length in our analyses, whereas flow cytometry-estimated superoxide level was negatively impacting offspring telomere length. We suggest that the effects of superoxide on hatchling telomere shortening may be partly balanced by transgenerational effects of vitellogenin antioxidation.
端粒会因DNA复制而缩短，尤其是在端粒酶产量低的细胞中，可能还会因暴露于活性氧（如超氧化物）所产生的生理应激而缩短。端粒磨损的这一过程会被天然抗氧化作用抵消，比如通过超氧化物歧化酶的产生。我们研究了澳大利亚彩绘石龙子（Ctenophorus pictus）中端粒长度的遗传情况，以及端粒长度与经体重校正的母体生殖投资共变的程度，后者反映了循环卵黄前体和抗氧化剂卵黄蛋白原的水平。我们对后代端粒长度的预测因子解释了72%的端粒变异（如果存在间质性端粒，则包括间质性端粒）。在我们的分析中，母体端粒长度和生殖投资对后代端粒长度有正向影响，而流式细胞术估计的超氧化物水平对后代端粒长度有负向影响。我们认为，超氧化物对幼体端粒缩短的影响可能会因卵黄蛋白原抗氧化作用的跨代效应而得到部分平衡。
