Department of Biochemistry and Molecular Biology, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA.
Cells. 2022 Jan 19;11(3):330. doi: 10.3390/cells11030330.
Heterochromatin has historically been considered the dark side of the genome. In part, this reputation derives from its concentration near centromeres and telomeres, regions of the genome repressive to nuclear functions such as DNA replication and transcription. The repetitive nature of heterochromatic DNA has only added to its "darkness", as sequencing of these DNA regions has been only recently achieved. Despite such obstacles, research on heterochromatin blossomed over the past decades. Success in this area benefitted from efforts of Sergio Pimpinelli and colleagues who made landmark discoveries and promoted the growth of an international community of researchers. They discovered complexities of heterochromatin, demonstrating that a key component, Heterochromatin Protein 1a (HP1a), uses multiple mechanisms to associate with chromosomes and has positive and negative effects on gene expression, depending on the chromosome context. In addition, they updated the work of Carl Waddington using molecular tools that revealed how environmental stress promotes genome change due to transposable element movement. Collectively, their research and that of many others in the field have shined a bright light on the dark side of the genome and helped reveal many mysteries of heterochromatin.
异染色质在历史上一直被认为是基因组的阴暗面。部分原因是它集中在着丝粒和端粒附近，基因组的这些区域对核功能（如 DNA 复制和转录）具有抑制作用。异染色质 DNA 的重复性质只会增加其“黑暗”程度，因为这些 DNA 区域的测序直到最近才得以实现。尽管存在这些障碍，但过去几十年来，异染色质的研究蓬勃发展。该领域的成功得益于 Sergio Pimpinelli 及其同事的努力，他们取得了里程碑式的发现，并促进了一个国际研究人员社区的发展。他们发现了异染色质的复杂性，表明关键成分异染色质蛋白 1a（HP1a）使用多种机制与染色体结合，并根据染色体的上下文对基因表达产生正反两方面的影响。此外，他们使用分子工具更新了 Carl Waddington 的工作，揭示了环境压力如何通过转座元件的运动促进基因组变化。总的来说，他们的研究和该领域的许多其他研究都为基因组的阴暗面带来了光明，并帮助揭示了异染色质的许多奥秘。
