Maternal loading of a small heat shock protein increases embryo thermal tolerance in Drosophila melanogaster

Maternal investment is likely to have direct effects on offspring survival. In oviparous animals whose embryos are exposed to the external environment, maternal provisioning of molecular factors like mRNAs and proteins may help embryos cope with sudden changes in the environment. Here we sought to modify the maternal mRNA contribution to offspring embryos and test for maternal effects on acute thermal tolerance in early embryos of Drosophila melanogaster. We drove in vivo overexpression of a small heat shock protein gene (Hsp23) in female ovaries and measured the effects of acute thermal stress on offspring embryonic survival and larval development. We report that overexpression of the Hsp23 gene in female ovaries produced offspring embryos with increased thermal tolerance. We also found that brief heat stress in the early embryonic stage (0 to 1 hour-old) caused decreased larval performance later in life (5 to 10 days-old), as indexed by pupation height. Maternal overexpression of Hsp2...

母体投资大概率对子代存活存在直接影响。针对胚胎暴露于外部环境的卵生动物而言，母体提供的mRNA、蛋白质等分子因子，或可帮助胚胎应对环境的突发变化。本研究旨在调控母体对子代胚胎的mRNA贡献，并检验其对黑腹果蝇（Drosophila melanogaster）早期胚胎急性热耐受性的母体效应。我们在雌性卵巢中诱导了小型热休克蛋白基因（small heat shock protein gene，Hsp23）的体内过表达，并检测了急性热胁迫对子代胚胎存活与幼虫发育的影响。研究结果表明，在雌性卵巢中过表达Hsp23基因可使子代胚胎的热耐受性显著提升。此外本研究还发现，早期胚胎阶段（0至1小时龄）的短暂热胁迫，会在子代生命后期（5至10日龄）降低其幼虫表现，该效应可通过化蛹高度得以体现。母体Hsp23过表达……