当前位置: X-MOL 学术Genome Biol. Evol. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
The Influence of Chromosomal Environment on X-Linked Gene Expression in Drosophila melanogaster
Genome Biology and Evolution ( IF 3.3 ) Pub Date : 2020-10-26 , DOI: 10.1093/gbe/evaa227
Aleksei Belyi 1 , Eliza Argyridou 1 , John Parsch 1
Affiliation  

Sex chromosomes often differ from autosomes with respect to their gene expression and regulation. In Drosophila melanogaster, X-linked genes are dosage compensated by having their expression upregulated in the male soma, a process mediated by the X-chromosome-specific binding of the dosage compensation complex (DCC). Previous studies of X-linked gene expression found a negative correlation between a gene’s male-to-female expression ratio and its distance to the nearest DCC binding site in somatic tissues, including head and brain, which suggests that dosage compensation influences sex-biased gene expression. A limitation of the previous studies, however, was that they focused on endogenous X-linked genes and, thus, could not disentangle the effects of chromosomal position from those of gene-specific regulation. To overcome this limitation, we examined the expression of an exogenous reporter gene inserted at many locations spanning the X chromosome. We observed a negative correlation between the male-to-female expression ratio of the reporter gene and its distance to the nearest DCC binding site in somatic tissues, but not in gonads. A reporter gene’s location relative to a DCC binding site had greater influence on its expression than the local regulatory elements of neighboring endogenous genes, suggesting that intra-chromosomal variation in the strength of dosage compensation is a major determinant of sex-biased gene expression. Average levels of sex-biased expression did not differ between head and brain, but there was greater positional effect variation in the brain, which may explain the observed excess of endogenous sex-biased genes located on the X chromosome in this tissue.

中文翻译:

染色体环境对黑腹果蝇X连锁基因表达的影响

性染色体通常在基因表达和调控方面与常染色体不同。在果蝇中, X-连锁基因通过在雄性体细胞中的表达上调而得到剂量补偿,这是一个由剂量补偿复合物 (DCC) 的 X 染色体特异性结合介导的过程。先前对 X 连锁基因表达的研究发现,基因的男女表达比例与其与体细胞组织(包括头部和大脑)中最近的 DCC 结合位点的距离呈负相关,这表明剂量补偿会影响性别偏向基因表达。然而,先前研究的局限性在于,他们专注于内源性 X 连锁基因,因此无法将染色体位置的影响与基因特异性调控的影响分开。为了克服这一限制,我们检查了插入在 X 染色体许多位置的外源报告基因的表达。我们观察到报告基因的男女表达比率与其与体细胞组织中最近的 DCC 结合位点的距离之间呈负相关,但在性腺中没有。报告基因相对于 DCC 结合位点的位置对其表达的影响大于邻近内源基因的局部调节元件,这表明剂量补偿强度的染色体内变异是性别偏见基因表达的主要决定因素。头部和大脑之间性别偏见表达的平均水平没有差异,但大脑中存在更大的位置效应变异,这可能解释了观察到的位于该组织中 X 染色体上的内源性性别偏见基因过多。
更新日期:2020-12-06
down
wechat
bug