Department of Biology, Center for Genomics and Systems Biology, New York University, New York, NY 10003, USA.
G3 (Bethesda). 2022 Jul 29;12(8). doi: 10.1093/g3journal/jkac151.
Isolation of copy number variations and chromosomal duplications at high frequency in the laboratory suggested that Caenorhabditis elegans tolerates increased gene dosage. Here, we addressed if a general dosage compensation mechanism acts at the level of mRNA expression in C. elegans. We characterized gene dosage and mRNA expression in 3 chromosomal duplications and a fosmid integration strain using DNA-seq and mRNA-seq. Our results show that on average, increased gene dosage leads to increased mRNA expression, pointing to a lack of genome-wide dosage compensation. Different genes within the same chromosomal duplication show variable levels of mRNA increase, suggesting feedback regulation of individual genes. Somatic dosage compensation and germline repression reduce the level of mRNA increase from X chromosomal duplications. Together, our results show a lack of genome-wide dosage compensation mechanism acting at the mRNA level in C. elegans and highlight the role of epigenetic and individual gene regulation contributing to the varied consequences of increased gene dosage.
在实验室中高频分离拷贝数变异和染色体重复表明，秀丽隐杆线虫能耐受基因剂量的增加。在这里，我们研究了在秀丽隐杆线虫中是否存在一种普遍的mRNA 表达水平上的剂量补偿机制。我们使用 DNA-seq 和 mRNA-seq 对 3 个染色体重复和一个 fosmid 整合株的基因剂量和 mRNA 表达进行了表征。我们的结果表明，平均而言，增加的基因剂量导致 mRNA 表达增加，这表明没有全基因组的剂量补偿。同一染色体重复内的不同基因表现出不同程度的 mRNA 增加，这表明单个基因的反馈调节。体细胞剂量补偿和生殖细胞抑制减少了来自 X 染色体重复的 mRNA 增加水平。总之，我们的结果表明，在秀丽隐杆线虫中，没有全基因组的剂量补偿机制作用于 mRNA 水平，并强调了表观遗传和单个基因调节在增加基因剂量的不同后果中的作用。
