Farah Ugbad A, Fisher Kirsten M
Division of Biological Sciences, University of California San Diego, 9500 Gilman Dr, La Jolla, CA, 92093, USA.
Department of Biological Sciences, California State University Los Angeles, 5151 State University Dr, Los Angeles, CA, 90032, USA.
Sci Rep. 2025 Jan 15;15(1):2064. doi: 10.1038/s41598-025-86305-3.
The moss Syntrichia caninervis Mitt. is distributed throughout drylands globally, and often anchors ecologically significant communities known as biological soil crusts (biocrusts). The species occupies a variety of dryland habitats with varying levels of drought and temperature stress, suggesting the potential for ecological specialization within S. caninervis. Here, we sampled S. caninervis from sites along two elevation gradients and used restriction site associated DNA sequencing to compare the relative impacts of environmental factors and geospatial distances on genetic differentiation in S. caninervis populations. While we found no evidence of isolation by distance in our data, one environmental variable, mean annual precipitation (MAP), was found to be a positive predictor of F. An ecological association analysis identified 32 SNP alleles that covary significantly with MAP, 15 of which fall within the exonic regions of genes with annotations suggesting diverse roles in response to dehydration stress. Understanding the degree to which genetic variation in S. caninervis is associated with environmental factors is key to predicting its potential for persistence in the face of global climate change, which is predicted to be especially detrimental to desert organisms already living at their physiological limits.
藓类植物犬齿藓（Syntrichia caninervis Mitt.）分布于全球旱地，常附着于具有重要生态意义的生物土壤结皮（生物结皮）群落。该物种占据了各种具有不同干旱和温度胁迫程度的旱地生境，这表明犬齿藓内部存在生态特化的潜力。在这里，我们从沿着两个海拔梯度的地点采集了犬齿藓样本，并使用限制性位点相关DNA测序来比较环境因素和地理空间距离对犬齿藓种群遗传分化的相对影响。虽然在我们的数据中没有发现距离隔离的证据，但发现一个环境变量，即年平均降水量（MAP），是F的正向预测因子。生态关联分析确定了32个与MAP显著共变的单核苷酸多态性（SNP）等位基因，其中15个位于基因的外显子区域，注释表明这些基因在应对脱水胁迫中具有多种作用。了解犬齿藓的遗传变异与环境因素的关联程度是预测其在全球气候变化面前的生存潜力的关键，预计全球气候变化对已经生活在生理极限的沙漠生物尤其有害。
