Alexandre Cristina M, Bubb Kerry L, Schultz Karla M, Lempe Janne, Cuperus Josh T, Queitsch Christine
Department of Genome Sciences, University of Washington, Seattle WA 98195, USA.
Julius Kühn Institute (JKI) - Federal Research Centre for Cultivated Plants, Institute for Breeding Research on Fruit Crops, Dresden, Germany.
bioRxiv. 2023 Sep 20:2023.05.11.540469. doi: 10.1101/2023.05.11.540469.
Isogenic individuals can display seemingly stochastic phenotypic differences, limiting the accuracy of genotype-to-phenotype predictions. The extent of this phenotypic variation depends in part on genetic background, raising questions about the genes involved in controlling stochastic phenotypic variation. Focusing on early seedling traits in , we found that hypomorphs of the cuticle-related gene greatly increased variation in seedling phenotypes, including hypocotyl length, gravitropism and cuticle permeability. Many hypocotyls were significantly shorter than wild-type hypocotyls while others resembled the wild type. Differences in epidermal properties and gene expression between seedlings with long and short hypocotyls suggest a loss of cuticle integrity as the primary determinant of the observed phenotypic variation. We identified environmental conditions that reveal or mask the increased variation in hypomorphs, and found that increased expression of its closest paralog is necessary for phenotypes. Our results illustrate how decreased expression of a single gene can generate starkly increased phenotypic variation in isogenic individuals in response to an environmental challenge.
同基因个体可能表现出看似随机的表型差异，这限制了基因型到表型预测的准确性。这种表型变异的程度部分取决于遗传背景，这引发了关于控制随机表型变异所涉及基因的问题。以[具体植物名称]的早期幼苗性状为研究重点，我们发现角质层相关基因的亚效等位基因极大地增加了幼苗表型的变异，包括下胚轴长度、向重力性和角质层通透性。许多[植物名称]的下胚轴明显短于野生型下胚轴，而其他的则与野生型相似。长下胚轴和短下胚轴的[植物名称]幼苗在表皮特性和基因表达上的差异表明，角质层完整性的丧失是观察到的表型变异的主要决定因素。我们确定了揭示或掩盖[植物名称]亚效等位基因变异增加的环境条件，并发现其最接近的旁系同源基因的表达增加对[植物名称]的表型是必要的。我们的结果说明了单个基因表达的降低如何在同基因个体中因环境挑战而导致表型变异显著增加。
