Animals with temperature-dependent sex determination (TSD) respond to thermal cues during early embryonic development to trigger gonadal differentiation. TSD has primarily been studied using constant temperature incubations, where embryos are exposed to constant male- or female-producing temperatures, and these studies have identified genes that display sex-specific expression in response to incubation temperature. Kdm6b, a histone demethylase gene, has received specific attention as it is among the initial genes to respond to incubation temperature and is necessary for testis development. Interestingly, Kdm6b retains an intron when eggs are incubated at a constant male-producing temperature, but the role of thermal variability in this developmental process is relatively understudied. Species with TSD regularly experience thermal cues that fluctuate between male- and female-producing temperatures throughout development but it is unclear how Kdm6b responds to such variable temperatures. In this study, we investigate temperature-sensitive splicing in Kdm6b by exposing embryos to male- and female-producing thermal conditions. We show a rapid decrease in levels of the intron retaining transcript of Kdm6b upon exposure to female-producing conditions. These results demonstrate that, under ecologically relevant conditions, temperature-sensitive splicing can differentially regulate genes critical to TSD.

具有温度依赖性性别决定（TSD）的动物在早期胚胎发育过程中对热信号做出反应，从而引发性腺分化。 TSD 主要通过恒温孵化进行研究，其中胚胎暴露于恒定的雄性或雌性生产温度下，这些研究已经鉴定出响应孵化温度而表现出性别特异性表达的基因。 Kdm6b是一种组蛋白去甲基化酶基因，它受到了特别关注，因为它是对孵化温度做出反应的初始基因之一，并且是睾丸发育所必需的。有趣的是，当卵子在恒定的雄性生产温度下孵化时， Kdm6b保留了一个内含子，但热变异在这一发育过程中的作用相对而言还没有得到充分研究。患有 TSD 的物种在整个发育过程中经常会经历雄性和雌性产生温度之间波动的热信号，但目前尚不清楚Kdm6b如何响应这种变化的温度。在这项研究中，我们通过将胚胎暴露于产生雄性和雌性的热条件来研究Kdm6b中的温度敏感剪接。我们发现，当暴露于雌性产生条件时， Kdm6b内含子保留转录物的水平迅速下降。这些结果表明，在生态相关条件下，温度敏感剪接可以差异性地调节对 TSD 至关重要的基因。