Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
University of Chinese Academy of Sciences, Beijing 100049, China.
Plant Cell. 2018 Oct;30(10):2286-2307. doi: 10.1105/tpc.18.00313. Epub 2018 Oct 11.
Sorghum () is the fifth most popular crop worldwide and a C model plant. Domesticated sorghum comes in many forms, including sweet cultivars with juicy stems and grain sorghum with dry, pithy stems at maturity. The locus, which controls the pithy/juicy stem trait, was discovered over a century ago. Here, we found that gene encodes a plant-specific NAC transcription factor. was either deleted or acquired loss-of-function mutations in sweet sorghum, resulting in cell collapse and altered secondary cell wall composition in the stem. Twenty-three ancestral haplotypes, all with dry, pithy stems, were found among wild sorghum and wild sorghum relatives. Two of the haplotypes were detected in domesticated landraces, with four additional haplotypes with juicy stems detected in improved lines. These results imply that selection for gene mutations was a major step leading to the origin of sweet sorghum. The gene is conserved in major cereals; fine-tuning its regulatory network could provide a molecular tool to control crop stem texture.
高粱（Sorghum）是全球第五大受欢迎的作物，也是 C 模式植物。栽培高粱有多种形式，包括多汁茎的甜品种和成熟时干燥、多髓的粮食高粱。控制髓质/多汁茎特性的 基因座在一个多世纪前就被发现了。在这里，我们发现 基因编码一个植物特异性的 NAC 转录因子。在甜高粱中，要么缺失，要么获得了失去功能的突变，导致茎中的细胞崩溃和次生细胞壁组成发生改变。在野生高粱和野生高粱亲缘种中发现了 23 个 祖先单倍型，所有这些单倍型都具有干燥、多髓的茎。在驯化的地方品种中检测到了两个单倍型，在改良系中还检测到了四个具有多汁茎的额外 单倍型。这些结果表明，对 基因突变的选择是导致甜高粱起源的主要步骤。 基因在主要谷物中保守；精细调整其调控网络可以为控制作物茎质地提供分子工具。
