Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, NC, USA.
Integrative Program for Biological and Genome Sciences, University of North Carolina, Chapel Hill, NC, USA.
Nucleus. 2023 Dec;14(1):2293604. doi: 10.1080/19491034.2023.2293604. Epub 2023 Dec 14.
Histone locus bodies (HLBs) are biomolecular condensates that assemble at replication-dependent (RD) histone genes in animal cells. These genes produce unique mRNAs that are not polyadenylated and instead end in a conserved 3' stem loop critical for coordinated production of histone proteins during S phase of the cell cycle. Several evolutionarily conserved factors necessary for synthesis of RD histone mRNAs concentrate only in the HLB. Moreover, because HLBs are present throughout the cell cycle even though RD histone genes are only expressed during S phase, changes in HLB composition during cell cycle progression drive much of the cell cycle regulation of RD histone gene expression. Thus, HLBs provide a powerful opportunity to determine the cause-and-effect relationships between nuclear body formation and cell cycle regulated gene expression. In this review, we focus on progress during the last five years that has advanced our understanding of HLB biology.
组蛋白基因座体（HLB）是在动物细胞中复制依赖性（RD）组蛋白基因处组装的生物分子凝聚物。这些基因产生独特的非多聚腺苷酸化的 mRNA，其 3'端茎环结构保守，对于细胞周期 S 期组蛋白蛋白的协调产生至关重要。几种对于 RD 组蛋白 mRNA 合成所必需的进化上保守的因子仅集中在 HLB 中。此外，由于 HLBs 存在于整个细胞周期中，即使 RD 组蛋白基因仅在 S 期表达，因此在细胞周期进展过程中 HLB 组成的变化驱动了 RD 组蛋白基因表达的大部分细胞周期调控。因此，HLB 为确定核体形成与细胞周期调控基因表达之间的因果关系提供了有力的机会。在这篇综述中，我们重点介绍了过去五年中推进我们对 HLB 生物学理解的进展。
