Data_Sheet_1_Identification of Quantitative Trait Loci for Altitude Adaptation of Tree Leaf Shape With Populus szechuanica in the Qinghai-Tibetan Plateau.CSV

As an important functional organ of plants, leaves alter their shapes in response to a changing environment. The variation of leaf shape has long been an important evolutionary and developmental force in plants. Despite an increasing amount of investigations into the genetic controls of leaf morphology, few have systematically studied the genetic architecture controlling shape differences among distinct altitudes. Altitude denotes a comprehensive complex of environmental factors affecting plant growth in many aspects, e.g., UV-light radiation, temperature, and humidity. To reveal how plants alter ecological adaptation to altitude through genes, we used Populus szechuanica var. tibetica growing on the Qinghai-Tibetan plateau. FST between the low- and high- altitude population was 0.00748, QST for leaf width, length and area were 0.00924, 0.1108, 0.00964 respectively. With the Elliptic Fourier-based morphometric model, association study of leaf shape was allowed, the dissection of the pleiotropic expression of genes mediating altitude-derived leaf shape variation was performed. For high and low altitudes, 130 and 131 significant single-nucleotide polymorphisms (SNPs) were identified. QTLs that affected leaf axis length and leaf width were expressed in both-altitude population, while QTLs regulating “leaf tip” and “leaf base” were expressed in low-altitude population. Pkinase and PRR2 were common significant genes in both types of populations. Auxin-related and differentiation-related genes included PIN1, CDK-like, and CAK1AT at high altitude, whereas they included NAP5, PIN-LIKES, and SCL1 at low altitude. The presence of Stress-antifung gene, CIPK3 and CRPK1 in high-altitude population suggested an interaction between genes and harsh environment in mediating leaf shape, while the senescence repression-related genes (EIN2 and JMJ18) and JMT in jasmonic acid pathway in low-altitude population suggested their crucial roles in ecological adaptability. These data provide new information that strengthens the understanding of genetic control with respect to leaf shape and constitute an entirely novel perspective regarding leaf adaptation and development in plants.

作为植物重要的功能器官，叶片会响应多变的环境而改变自身形态。叶形变异长期以来都是植物演化与发育进程中的重要驱动力。尽管针对叶片形态的遗传调控机制已有日益增多的研究，但鲜有研究系统解析不同海拔梯度间叶形差异的遗传架构。海拔（Altitude）是一系列综合复杂的环境因子的集合，会从多维度影响植物生长，例如紫外（UV-light）辐射、温度与湿度。为揭示植物如何通过基因调控实现对海拔梯度的生态适应，本研究选取了生长于青藏高原的西藏杨（Populus szechuanica var. tibetica）作为实验材料。低海拔与高海拔种群间的遗传分化系数（FST）为0.00748；叶宽、叶长与叶面积的数量性状分化指数（QST）分别为0.00924、0.1108与0.00964。本研究采用基于椭圆傅里叶的形态计量模型（Elliptic Fourier-based morphometric model）开展叶形关联分析，对介导海拔驱动的叶形变异的基因多效性表达模式进行了解析。在高海拔与低海拔种群中，分别鉴定得到130个与131个显著单核苷酸多态性位点（single-nucleotide polymorphisms, SNPs）。调控叶轴长度与叶宽的数量性状基因座（Quantitative Trait Locus, QTL）在两类种群中均有表达，而调控"叶尖"与"叶基"的QTL仅在低海拔种群中被检测到。蛋白激酶（Pkinase）与PRR2是两类种群共有的显著关联基因。高海拔种群中，与生长素相关及分化相关的基因包括PIN1、类细胞周期蛋白依赖激酶（CDK-like）与CAK1AT；而低海拔种群中的此类基因则包含NAP5、PIN样蛋白（PIN-LIKES）与SCL1。高海拔种群中存在抗逆真菌基因（Stress-antifung gene）、CIPK3与CRPK1，这表明介导叶形变异的基因与严苛环境之间存在互作调控关系；而低海拔种群中的衰老抑制相关基因EIN2与JMJ18，以及茉莉酸途径中的JMT，则提示它们在植物生态适应性中发挥关键作用。本研究的数据为深化人们对叶形遗传调控机制的认知提供了新的科学依据，同时也为植物叶形适应与发育的研究构建了全新的视角。