Using pea as our model crop, we sought to understand the regulatory control over the import of sugars and amino acids into the developing seeds and its importance for seed yield and quality. Transgenic peas simultaneously overexpressing a sucrose transporter and an amino acid transporter were developed. Pod walls, seed coats, and cotyledons were analysed separately, as well as leaves subtending developing pods. Sucrose, starch, protein, free amino acids, and endogenous cytokinins were measured during development. Temporal gene expression analyses (RT-qPCR) of amino acid (AAP), sucrose (SUT), and SWEET transporter family members, and those from cell wall invertase, cytokinin biosynthetic (IPT) and degradation (CKX) gene families indicated a strong effect of the transgenes on gene expression. In seed coats of the double transgenics, increased content and prolonged presence of cytokinin was particularly noticeable. The transgenes effectively promoted transition of young sink leaves into source leaves. We suggest the increased flux of sucrose and amino acids from source to sink, along with increased interaction between cytokinin and cell wall invertase in developing seed coats led to enhanced sink activity, resulting in higher cotyledon sucrose at process pea harvest, and increased seed number and protein content at maturity.

使用豌豆作为我们的模型作物，我们试图了解对正在发育的种子中糖和氨基酸的进口的监管控制及其对种子产量和质量的重要性。开发了同时过表达蔗糖转运蛋白和氨基酸转运蛋白的转基因豌豆。分别分析豆荚壁、种皮和子叶，以及包覆正在发育的豆荚的叶子。在发育过程中测量蔗糖、淀粉、蛋白质、游离氨基酸和内源细胞分裂素。氨基酸 ( AAP )、蔗糖 ( SUT ) 和SWEET转运蛋白家族成员以及细胞壁转化酶、细胞分裂素生物合成 ( IPT ) 和降解 ( CKX ) 基因家族的时间基因表达分析 (RT-qPCR) 表明具有很强的作用转基因对基因表达的影响。在双转基因的种皮中，细胞分裂素的含量增加和存在时间延长尤其明显。转基因有效地促进了幼小的库叶向源叶的转变。我们认为，蔗糖和氨基酸从源到库的流量增加，以及种皮发育中细胞分裂素和细胞壁转化酶之间相互作用的增加，导致库活性增强，导致加工豌豆收获时子叶蔗糖含量更高，种子数量和种子数量增加。成熟时的蛋白质含量。