Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada L8S 4K1.
Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada L8S 4K1
Genetics. 2020 Jun;215(2):483-495. doi: 10.1534/genetics.120.303125. Epub 2020 Mar 30.
The nematode is protected from the environment by the cuticle, an extracellular collagen-based matrix that encloses the animal. Over 170 cuticular collagens are predicted in the genome, but the role of each individual collagen is unclear. Stage-specific specialization of the cuticle explains the need for some collagens; however, the large number of collagens suggests that specialization of the cuticle may also occur in response to other environmental triggers. Missense mutations in many collagen genes can disrupt cuticle morphology, producing a helically twisted body causing the animal to move in a stereotypical pattern described as rolling. We find that environmental factors, including diet, early developmental arrest, and population density can differentially influence the penetrance of rolling in these mutants. These effects are in part due to changes in collagen gene expression that are mediated by the GATA family transcription factor ELT-3 We propose a model by which ELT-3 regulates collagen gene expression in response to environmental stimuli to promote the assembly of a cuticle specialized to a given environment.
线虫由角质层保护，角质层是一种细胞外胶原蛋白基质，包裹着动物。在 基因组中预测了超过 170 种角质层胶原蛋白，但每个胶原蛋白的作用尚不清楚。角质层的阶段特异性特化解释了某些胶原蛋白的必要性；然而，大量的胶原蛋白表明，角质层的特化也可能是对其他环境触发因素的反应。许多胶原蛋白基因中的错义突变会破坏角质层形态，导致身体产生螺旋扭曲，使动物以一种被描述为滚动的典型模式移动。我们发现，环境因素，包括饮食、早期发育停滞和种群密度，可以不同程度地影响这些突变体中滚动的外显率。这些影响部分归因于胶原蛋白基因表达的变化，这些变化是由 GATA 家族转录因子 ELT-3 介导的。我们提出了一个模型，即 ELT-3 响应环境刺激调节胶原蛋白基因表达，以促进专门针对特定环境的角质层的组装。
