Yu Hao-Yue, Zhang You-Huan, Li Hang, Feng Hong
Sichuan Key Laboratory of Molecular Biology and Biotechnology, College of Life Sciences, Sichuan University, Chengdu, 610064, P. R. China.
BMC Genomics. 2025 Jul 21;26(1):681. doi: 10.1186/s12864-025-11856-8.
Highland barley (Hordeum vulgare L. var. nudum) is a key crop of the Qinghai-Tibet Plateau, renowned for its nutritional value and exceptional adaptability to high-altitude environments. Induced mutagenesis offers a powerful approach to developing new crop varieties and elucidating the genetic basis of functional traits.
In this study, nitrogen ion beam implantation was employed to induce mutations in the highland barley cultivar Kunlun 14 (K14), generating 71 novel mutation materials and enriching the genetic resources for barley breeding. Phenotypic trait correlation analysis identified two mutation lines exhibiting significant variations: E8-38 with highly increased 1000-grain weight, and D7-67 displaying a two-row spike phenotype. Comparative transcriptomic analysis was applied to the above two mutation materials. It was revealed that the high 1000-grain weight of E8-38 was driven by synergistic regulation of phytohormone signaling, metabolic pathways, and epigenetic modifications, particularly the upregulation of the cytokinins signaling pathway and starch metabolism genes. In D7-67, the two-rowed spike phenotype was underpinned by the upregulation of VRS1 genes. Adaptive mechanisms to high-altitude environments were investigated, revealing upregulation of PAL and 4CL genes in phenylpropanoid biosynthesis, which enhances UV resistance and antioxidant capacity. Additionally, optimization of the photosynthetic pathway may contribute to acclimation under harsh stress conditions. Through PPI analysis, BZIP transcription factors were found to regulate downstream genes, facilitating adaptation to light changes and oxidative stress.
Nitrogen ion beam implantation was demonstrated to be an efficiency method to introduce mutation on the highland barley, generating a set of mutation materials with a wide range of genetic variations. Through comparative transcriptomic analysis, this study elucidates the molecular basis underlying the 1000-grain weight and spike-type mutants, as well as the adaptive mechanisms enabling highland barley to thrive in high-altitude environments. These findings provide critical insights into the genetic and molecular mechanisms driving high-yield and stress-resilient traits in highland barley.
青稞（裸大麦）是青藏高原的一种关键作物，以其营养价值和对高海拔环境的卓越适应性而闻名。诱变是培育新作物品种和阐明功能性状遗传基础的有力方法。
在本研究中，采用氮离子束注入法对青稞品种昆仑14（K14）进行诱变，获得71份新的突变材料，丰富了大麦育种的遗传资源。表型性状相关性分析鉴定出两个表现出显著变异的突变系：千粒重显著增加的E8 - 38和具有二棱穗表型的D7 - 67。对上述两个突变材料进行了比较转录组分析。结果表明，E8 - 38的高千粒重是由植物激素信号传导、代谢途径和表观遗传修饰的协同调控驱动的，特别是细胞分裂素信号传导途径和淀粉代谢基因的上调。在D7 - 67中，二棱穗表型是由VRS1基因的上调所支撑。研究了对高海拔环境的适应机制，发现苯丙烷生物合成中PAL和4CL基因的上调增强了紫外线抗性和抗氧化能力。此外，光合途径的优化可能有助于在恶劣胁迫条件下的适应。通过蛋白质 - 蛋白质相互作用分析，发现BZIP转录因子调节下游基因，促进对光照变化和氧化应激的适应。
氮离子束注入被证明是一种在青稞上引入突变的有效方法，产生了一组具有广泛遗传变异的突变材料。通过比较转录组分析，本研究阐明了千粒重和穗型突变体的分子基础，以及青稞在高海拔环境中茁壮成长的适应机制。这些发现为驱动青稞高产和抗逆性状的遗传和分子机制提供了关键见解。
