Departamento de Genética, Escuela Técnica Superior de Ingeniería Agronómica y de Montes, Edificio Gregor Mendel, Campus de Rabanales, Universidad de Córdoba, CeiA3, ES-14071, Córdoba, Spain.
Plant Sci. 2021 Apr;305:110843. doi: 10.1016/j.plantsci.2021.110843. Epub 2021 Feb 6.
Wheat starch is composed of two glucose polymers, amylose and amylopectin. Although several starch synthases are responsible for its synthesis, only the waxy protein is associated with the amylose synthesis. The waxy protein composition of 45 Spanish common wheat landraces from Andalusia (southern Spain) was evaluated. Within these materials, five novel alleles for the Wx-A1 gene were detected. Four of them showed functional proteins (Wx-A1p, Wx-A1q, Wx-A1r and Wx-A1s), although some amino acid changes were found in the mature protein sequence. However, one of them (Wx-A1t) exhibited loss of the Wx-A1 protein, and its base sequence contained one large insert (1,073 bp) in the tenth exon, that interrupted the ORF of the Wx-A1 gene. This insert exhibited the characteristics of a Class II transposon of the Mutator superfamily, which had not been described previously, and has been named Baetica. The conservation of such inserts could be related to their low effect on vital properties of the plants, as occurs with most of the genes associated with technological quality. In conclusion, the evaluation of old wheat landraces showed that, in addition to their use as alternative crops, these materials could be a useful source of interesting genes in wheat quality improvement.
小麦淀粉由两种葡萄糖聚合物组成，直链淀粉和支链淀粉。尽管有几种淀粉合酶负责其合成，但只有蜡质蛋白与直链淀粉合成有关。评估了来自西班牙南部安达卢西亚（Andalusia）的 45 种西班牙普通小麦地方品种的蜡质蛋白组成。在这些材料中，检测到了 Wx-A1 基因的五个新等位基因。其中四个表现出功能性蛋白质（Wx-A1p、Wx-A1q、Wx-A1r 和 Wx-A1s），尽管在成熟蛋白质序列中发现了一些氨基酸变化。然而，其中一个（Wx-A1t）表现出 Wx-A1 蛋白的缺失，其碱基序列在第十个外显子中包含一个大插入（1073bp），该插入中断了 Wx-A1 基因的 ORF。该插入表现出 Mutator 超家族 II 类转座子的特征，以前尚未描述过，已将其命名为 Baetica。这种插入的保守性可能与其对植物重要特性的低影响有关，就像与技术质量相关的大多数基因一样。总之，对古老小麦地方品种的评估表明，除了作为替代作物的用途外，这些材料还可能是小麦品质改良中有趣基因的有用来源。
