Cover image: Pictured is a composite image of the eyespots of a wild-type Painted Lady butterfly (Vanessa cardui) (bottom left) and an ivory CRISPR mutant (top right). Luca Livraghi et al. used CRISPR/Cas9 to explore the effects of ivory, a long noncoding RNA, on wing pigmentation patterns in five nymphalid butterfly species. The authors found that ivory plays a central role in regulating transitions between dark and light-colored scales during pupal butterfly wing development. The results could help provide insight into the evolution of adaptive variations in butterfly coloration, such as mimicry. See the article by Livraghi et al. e2403326121. Image credit: Luca Livraghi.
PLANT PHYSIOLOGY:合肥工业大学揭示H2S介导的对ABA降解的调控机制
Hydrogen sulfide (H2S)是调控植物生长发育的一种重要的气态分子。本研究发现H2S可以延缓暗条件下诱发的叶片衰老过程。 转录组及基因表达分析证实了一个Ethylene Response Factor ERF.D3受到H2S的诱导，并被过硫化修饰，修饰位点是 C115 and C118. 转基因及突变分析显示ERF.D3负调控叶片衰老以及果实成熟过程。
在该转录因子的过表达株系中，ABA的水平显著下降。 转录分析显示，ABA降解途径中的8'-hydroxylase-encoding gene CYP707A2可以直接被ERF.D3 结合并诱导表达。H2S对ERF.D3的过硫化修饰提高了该转录因子对靶基因的表达调控能力。而E3 ligase RNF217 可以将ERF.D3泛素化, 从而促进了果实成熟。
小结：本研究揭示了H2S-通过ERF.D3抑制叶片衰老以及果实成熟过程的分子机制。
A model of the regulatory module, H2S-ERF.D3-CYP707A2 in regulating tomato leave senescence and fruit ripening. In immature tomato fruit or un-senescent tomato leaf, or under H2S treatment, ERF.D3 is activated at transcription level and modified through persulfidation which activates the transcription of ABA 8'-hydroxylase CYP707A2, and leads to the degradation of ABA, thereby maintaining the immature state of tomato leaf and fruit. The orange arrow in up penal means increase in the expression of ERF.D3 and the blue down arrow means decrease in ABA content. In ripening fruit or senescent leaf, ERF.D3 is mainly ubiquitinated by RNF217 which is highly expressed in ripening fruit and causes attenuated expression of CYP707A2 and increased level of ABA. The orange arrow in lower penal means increase in the expression of RNF217 and the orange up arrow means increase in ABA
content.
原文：The H2S-responsive transcription factor ERF.D3 regulates tomato abscisic acid metabolism, leaf senescence, and fruit ripening
