Rayner Tracey, Moreau Carol, Ambrose Mike, Isaac Peter G, Ellis Noel, Domoney Claire
John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK.
IDna Genetics Ltd, Centrum, Norwich Research Park, Norwich NR4 7UG, UK.
Int J Mol Sci. 2017 Jun 6;18(6):1205. doi: 10.3390/ijms18061205.
One of the traits studied by Mendel in pea ( L.) was the wrinkled-seeded phenotype, and the molecular basis for a mutation underlying this phenotype was discovered in the 1990s. Although the starch-branching enzyme gene mutation identified at the genetic locus is most likely to be that in seeds available to Mendel in the mid-1800s, it has remained an open question as to whether or not additional natural mutations in this gene exist within germplasm collections. Here, we explore this question and show that all but two wrinkled-seeded variants in one such collection correspond to either the mutant allele described previously for the locus or a mutation at a second genetic locus, , affecting the gene encoding the large subunit of Adenosine diphosphoglucose (ADP-glucose) pyrophosphorylase; the molecular basis for the mutation is described here. The genetic basis for the phenotype of one (JI 2110) of the two lines which are neither nor has been studied in crosses with a round-seeded variant (JI 281); for which extensive genetic marker data were expected. In marked contrast to the trait studied by Mendel and the phenotype; the data suggest that the wrinkled-seeded phenotype in JI 2110 is maternally determined, controlled by two genetic loci, and the extent to which it is manifested is very sensitive to the environment. Metabolite analysis of the cotyledons of JI 2110 revealed a profile for sucrose and sucrose-derived compounds that was more similar to that of wild-type round-seeded, than that of wrinkled-seeded , pea lines. However, the metabolite profile of the seed coat (testa) of JI 2110 was distinct from that of other round-seeded genotypes tested which, together with analysis of recombinant inbred progeny lines, suggests an explanation for the seed phenotype.
孟德尔在豌豆（L.）中研究的性状之一是皱粒种子表型，20世纪90年代发现了该表型潜在突变的分子基础。尽管在遗传位点鉴定出的淀粉分支酶基因突变很可能就是19世纪中叶孟德尔所研究种子中的突变，但在种质资源库中该基因是否存在其他自然突变仍是一个悬而未决的问题。在此，我们探讨了这个问题，并表明在一个这样的种质资源库中，除了两个皱粒种子变体之外，其他所有变体要么对应于先前描述的该位点的突变等位基因，要么对应于第二个遗传位点的突变，该突变影响编码二磷酸腺苷葡萄糖（ADP - 葡萄糖）焦磷酸化酶大亚基的基因；本文描述了该突变的分子基础。对于既非该位点突变也非另一位点突变的两个品系之一（JI 2110）的表型遗传基础，已通过与一个圆粒种子变体（JI 281）杂交进行了研究；预计会得到大量的遗传标记数据。与孟德尔研究的性状和该位点突变的表型形成显著对比的是；数据表明JI 2110中的皱粒种子表型是母性决定的，由两个遗传位点控制，并且其表现程度对环境非常敏感。对JI 2110子叶的代谢物分析表明，蔗糖和蔗糖衍生化合物的谱型与野生型圆粒种子更相似，而与皱粒种子的豌豆品系不同。然而，JI 2110种皮（种 testa）的代谢物谱型与所测试的其他圆粒种子基因型不同，这与重组自交后代品系的分析一起，为种子表型提供了一种解释。
