Overlander-Chen Megan, Fiedler Jason D, Zhong Shaobin, Yang Shengming
USDA-ARS Cereals Research Improvement Unit, Edward T. Schafer Agriculture Research Center, Fargo, ND, 58102, USA.
Department of Plant Sciences, North Dakota State University, Fargo, ND, 58102, USA.
BMC Plant Biol. 2025 Jul 2;25(1):797. doi: 10.1186/s12870-025-06790-6.
Stem development is crucial for plant lodging, nutrients and water transport, and structural support for other organs. Understanding stem development and growth is essential for ensuring global food security. Although numerous lodging-resilient and high-yielding crop varieties have been developed in the Green Revolution by controlling plant height, the molecular mechanism underlying stem development, particularly for cereals, is not fully understood. The allelic stem mutants in barley (Hordeum vulgare subsp. vulgare), single internode dwarf 1 (sid1), provide a model system for genetic studies on stem development.
We characterized and genetically analyzed the sid1.b mutation. To determine the precise position of Sid1, a high-resolution genetic map was constructed. Segregating F plants derived from a cross between wild type (WT) and the mutant were genotyped with the barley 50 k iSelect SNP Array, and the detected SNPs were converted to PCR-based markers for fine mapping. The Sid1 gene was mapped to a 429-kb region on chromosome 4H. Illumina sequencing of WT and sid1 identified a C → T transition in an epidermal pattern factor (EPF)-coding gene, which introduces a premature stop codon in the mutant allele.
In the present study, we genetically characterized and mapped the sid1.a mutation, which causes a dwarfed phenotype with single internode stems in barley. The EPF-encoding gene in the delimited region is a promising candidate for Sid1. Therefore, our study provides a foundation for cloning of Sid1, which will enhance our understanding of the molecular mechanisms underlying stem development, particularly in monocot plants.
茎的发育对于植物抗倒伏、养分和水分运输以及对其他器官的结构支撑至关重要。了解茎的发育和生长对于确保全球粮食安全至关重要。尽管在绿色革命中通过控制株高培育出了许多抗倒伏和高产的作物品种，但茎发育的分子机制，尤其是谷类作物的分子机制，尚未完全了解。大麦（Hordeum vulgare subsp. vulgare）中的等位茎突变体，单节间矮化1（sid1），为茎发育的遗传研究提供了一个模型系统。
我们对sid1.b突变进行了表征和遗传分析。为了确定Sid1的精确位置，构建了一个高分辨率遗传图谱。用大麦50k iSelect SNP阵列对野生型（WT）和突变体杂交产生的分离F植株进行基因分型，并将检测到的SNP转化为基于PCR的标记进行精细定位。Sid1基因被定位到4H染色体上一个429kb的区域。WT和sid1的Illumina测序在一个表皮模式因子（EPF）编码基因中鉴定出一个C→T转换，该转换在突变等位基因中引入了一个提前终止密码子。
在本研究中，我们对sid1.a突变进行了遗传表征和定位，该突变导致大麦出现单节间茎的矮化表型。限定区域内的EPF编码基因是Sid1的一个有希望的候选基因。因此，我们的研究为克隆Sid1奠定了基础，这将增进我们对茎发育分子机制的理解，特别是在单子叶植物中。
