Liu Qian, Liu Yang, Shi Qinghua, Su Handong, Wang Chunhui, Birchler James A, Han Fangpu
State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing, 100101, China.
University of Chinese Academy of Sciences, Beijing, 100049, China.
Genes Genomics. 2021 Mar;43(3):217-226. doi: 10.1007/s13258-021-01041-y. Epub 2021 Feb 1.
Centromeres are specialized chromosomal domains involved in kinetochore formation and faithful chromosome segregation. Despite a high level of functional conservation, centromeres are not identified by DNA sequences, but by epigenetic means. Universally, centromeres are typically formed on highly repetitive DNA, which were previously considered to be silent. However, recent studies have shown that transcription occurs in this region, known as centromeric-derived RNAs (cenRNAs). CenRNAs that contribute to fundamental aspects of centromere function have been recently investigated in detail. However, the distribution, behavior and contributions of centromeric transcripts are still poorly understood.
The aim of this article is to provide an overview of the roles of cenRNAs in centromere formation and function.
We describe the structure and DNA sequence of centromere from yeast to human. In addition, we briefly introduce the roles of cenRNAs in centromere formation and function, kinetochore structure, accurate chromosome segregation, and pericentromeric heterochromatin assembly. Centromeric circular RNAs (circRNAs) and R-loops are rising stars in centromere function. CircRNAs have been successfully identified in various species with the assistance of high-throughput sequencing and novel computational approaches for non-polyadenylated RNA transcripts. Centromeric R-loops can be identified by the single-strand DNA ligation-based library preparation technique. But the molecular features and function of these centromeric R-loops and circRNAs are still being investigated.
In this review, we summarize recent findings on the epigenetic regulation of cenRNAs across species, which would provide useful information about cenRNAs and interesting hints for further studies.
着丝粒是参与动粒形成和染色体忠实分离的特殊染色体结构域。尽管着丝粒具有高度的功能保守性，但它们不是由DNA序列来识别，而是通过表观遗传方式来识别。一般来说，着丝粒通常在高度重复的DNA上形成，这些DNA以前被认为是沉默的。然而，最近的研究表明，该区域会发生转录，产生着丝粒衍生RNA（cenRNAs）。最近已经详细研究了对着丝粒功能基本方面有贡献的cenRNAs。然而，着丝粒转录本的分布、行为和作用仍知之甚少。
本文旨在概述cenRNAs在着丝粒形成和功能中的作用。
我们描述了从酵母到人类的着丝粒的结构和DNA序列。此外，我们简要介绍了cenRNAs在着丝粒形成和功能、动粒结构、精确的染色体分离以及着丝粒周围异染色质组装中的作用。着丝粒环状RNA（circRNAs）和R环是着丝粒功能研究中的后起之秀。借助高通量测序和针对非聚腺苷酸化RNA转录本的新型计算方法，已在各种物种中成功鉴定出circRNAs。着丝粒R环可通过基于单链DNA连接的文库制备技术来鉴定。但这些着丝粒R环和circRNAs的分子特征和功能仍在研究中。
在本综述中，我们总结了近期关于跨物种cenRNAs表观遗传调控的研究发现，这将为cenRNAs提供有用信息，并为进一步研究提供有趣的线索。
