Alternative splicing of POUM2 regulates embryonic cuticular formation and tanning in Bombyx mori
Alternative splicing of POUM2 regulates embryonic cuticular formation and tanning in Bombyx mori
复制标题
POUM2 的选择性剪接调节家蚕胚胎角质层的形成和晒黑
DOI：
10.1111/1744-7917.13164
复制
发表时间：
2023-02-08
期刊：
影响因子：
4
通讯作者：
Deng，Huimin
中科院分区：
文献类型：
--
作者：
Tong，Chunmei;Zhang，Kang;Deng，Huimin
昆虫角质层是一种顶端的细胞外基质，在胚胎发生时由表皮、气管、后肠和前肠上皮产生，并在蜕皮和变态过程中更新。然而，胚胎角质层形成的潜在调控机制在很大程度上仍不清楚。本文研究了转录因子poum2在鳞翅目昆虫家蚕胚胎表皮形成中的作用。聚集规律间隔的回转录重复序列(CRISPR)/CRISPR相关蛋白- 9介导的poum2基因敲除导致胚胎表皮沉积、色素沉着和硬化的缺陷。7 d龄胚胎的差异表达转录物分析发现，poum2−/−胚胎中有174个表皮蛋白转录物上调或下调，8个几丁质降解转录物上调，2个几丁质合成转录物下调，48个转录因子转录物上调或下调。在poum2−/−胚胎中，酪氨酸代谢途径的关键因子，如天冬氨酸羟化酶（Th）、多巴脱羧酶（DDC）和芳基烷基胺N -乙酰转移酶（aaNAT）的表达水平显著降低。POUM2异构体POUM2‐L特异性结合tho启动子中的POUcis调控元件（CRE）并增加th的转录，而POUM2‐S不能结合POU CRE，尽管它也增加了th的转录。异质核核糖核蛋白Squid‐1直接结合poum2 - LtoPOUM2 - SmRNA（信使RNA），抑制poum2 - LtoPOUM2 - SmRNA的选择性剪接。这些结果表明，在胚胎发生过程中，POUM2通过调节几丁质和角质层蛋白的合成和代谢参与角质层的形成，并通过调节酪氨酸代谢参与角质层的色素沉着和硬化。该研究为POUM2在胚胎发生中的新功能提供了新的见解。
Insect cuticle is an apical extracellular matrix produced by the epidermis, tracheal, hind‐ and foregut epithelia during embryogenesis and renewed during molting and metamorphosis. However, the underlying regulatory mechanism for embryonic cuticle formation remains largely unclear. Here, we investigate the function of the transcription factorPOUM2in the embryonic cuticular formation inBombyx mori, a model lepidopteran insect. Clustered regularly interspaced palindromic repeats (CRISPR)/CRISPR‐associated protein‐9‐mediated knockout ofPOUM2resulted in the defect of cuticular deposition, pigmentation, and sclerotization in the embryos. Differentially expressed transcripts analysis of 7‐d‐old embryos identified 174 up‐ or downregulated cuticular protein transcripts, 8 upregulated chitin degradation transcripts, 2 downregulated chitin synthesis transcripts and 48 up‐ or downregulated transcription factor transcripts in thePOUM2−/−embryos. The expression levels of the key factors of the tyrosine metabolic pathway, such astyrosine hydroxylase(Th),Dopa decarboxylase(DDC), andarylalkylamine N‐acetyltransferase(aaNAT), were significantly decreased in thePOUM2−/−embryos. POUM2 isoform POUM2‐L specifically bound the POUcis‐regulatory element (CRE) in theThpromoter and increased the transcription ofTh, whereas POUM2‐S could not bind the POU CRE, although it also increased the transcription ofTh. Heterogeneous nuclear ribonucleoprotein Squid‐1 directly bound thePOUM2pre‐mRNA (messenger RNA) and inhibited the alternative splicing ofPOUM2‐LtoPOUM2‐SmRNA. These results suggest that POUM2 participates in the cuticular formation by regulating the chitin and cuticular protein synthesis and metabolism, and the cuticular pigmentation and sclerotization by regulating tyrosine metabolism during embryogenesis. This study provides new insights into novel function of POUM2 in embryogenesis.