Zhou Rong, Yao Wenye, Xie Chundi, Zhang Leixia, Pei Yangli, Li Hua, Feng Zheng, Yang Yalan, Li Kui
Guangdong Provincial Key Laboratory of Animal Molecular Design and Precise Breeding, Key Laboratory of Animal Molecular Design and Precise Breeding of Guangdong Higher Education Institutes, School of Life Science and Engineering, Foshan University, Foshan, 528231 Guangdong China.
State Key Laboratory of Animal Nutrition; Key Laboratory of Animal Genetics Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, 100193 China.
J Anim Sci Biotechnol. 2020 Sep 7;11:90. doi: 10.1186/s40104-020-00495-6. eCollection 2020.
RNA editing is a widespread post-transcriptional modification mechanism in mammalian genomes. Although many editing sites have been identified in domestic pigs (), little is known about the characteristics and dynamic regulation of RNA editing in the pineal gland (PG), a small neuroendocrine gland that synthesizes and secretes melatonin, which is primarily responsible to modulate sleep patterns.
This study analyzed the expression of adenosine-to-inosine (A-to-I) editing regulators and profiled the first dynamic A-to-I RNA editome during postnatal PG development. The results identified as the most abundantly expressed ADAR enzyme, which was down-regulated during postnatal PG development. Furthermore, 47,284 high-confidence RNA editing sites were identified, the majority of which (93.6%) were of the canonical A-to-I editing type, followed by C-to-T editing. Analysis of its characteristics showed that the A-to-I editing sites mostly localized in SINE retrotransposons PRE-1/Pre0_SS. Moreover, a strong deficiency and preference for guanine nucleotides at positions of one base upstream or downstream were found, respectively. The overall editing level at the puberty stage was higher than at both infancy and adulthood stages. Additionally, genome-wide RNA editing was found to exhibit a dynamic stage-specific fashion (postnatally). Genes that underwent developmental changes in RNA editing were associated with catabolic processes as well as protein localization and transport functions, implying that RNA editing might be responsible for the molecular machineries of the postnatal developing PG. Remarkably, RNA editing in 3'-UTRs might regulate gene expression by influencing miRNA binding during PG development.
This study profiles the first comprehensive developmental RNA editome in the pig PG, which contributes to the understanding of the importance of post-transcriptionally mediated regulation during mammalian postnatal PG development. Moreover, this study widely extends RNA editome resources in mammals.
RNA编辑是哺乳动物基因组中一种广泛存在的转录后修饰机制。尽管在家猪中已鉴定出许多编辑位点，但对于松果体（PG）中RNA编辑的特征和动态调控知之甚少。松果体是一个小型神经内分泌腺，可合成和分泌褪黑素，主要负责调节睡眠模式。
本研究分析了腺苷到肌苷（A到I）编辑调节因子的表达，并描绘了出生后PG发育过程中的首个动态A到I RNA编辑组。结果确定[具体酶名未给出]为表达最丰富的ADAR酶，其在出生后PG发育过程中表达下调。此外，鉴定出47284个高可信度的RNA编辑位点，其中大多数（93.6%）为典型的A到I编辑类型，其次是C到T编辑。对其特征的分析表明，A到I编辑位点大多位于SINE反转录转座子PRE-1/Pre0_SS中。此外，分别在编辑位点上游或下游一个碱基位置发现了对鸟嘌呤核苷酸的强烈缺失和偏好。青春期的整体编辑水平高于婴儿期和成年期。此外，发现全基因组RNA编辑呈现出动态的阶段特异性模式（出生后）。经历RNA编辑发育变化的基因与分解代谢过程以及蛋白质定位和运输功能相关，这意味着RNA编辑可能负责出生后发育中的PG的分子机制。值得注意的是，3'-UTR中的RNA编辑可能通过影响PG发育过程中的miRNA结合来调节基因表达。
本研究描绘了猪PG中首个全面的发育RNA编辑组，这有助于理解转录后介导的调控在哺乳动物出生后PG发育中的重要性。此外，本研究广泛扩展了哺乳动物中的RNA编辑组资源。
