Cheng Kun, Pan Yi-Fan, Liu Lü-Meng, Zhang Han-Qing, Zhang Yuan-Ming
Crop Information Center, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China.
Front Plant Sci. 2021 Oct 26;12:743680. doi: 10.3389/fpls.2021.743680. eCollection 2021.
The seed oil and starch content of soybean are significantly different from that of chickpea. However, there are limited studies on its molecular mechanisms. To address this issue, we conducted integrated transcriptomic and bioinformatics analyses for species-specific genes and acyl-lipid-, starch-, and carbon metabolism-related genes. Among seven expressional patterns of soybean-specific genes, four were highly expressed at the middle- and late oil accumulation stages; these genes significantly enriched fatty acid synthesis and carbon metabolism, and along with common acetyl CoA carboxylase (ACCase) highly expressed at soybean middle seed development stage, common starch-degrading enzyme beta-amylase-5 (BAM5) was highly expressed at soybean early seed development stage and oil synthesis-related genes , and () were co-expressed with , which may result in high seed oil content and low seed starch content in soybean. The common ADP-glucose pyrophosphorylase (AGPase) was highly expressed at chickpea middle seed development stage, along with more starch biosynthesis genes co-expressed with four-transcription-factor homologous genes in chickpea than in soybean, and the common WRI1 was not co-expressed with oil synthesis genes in chickpea, which may result in high seed starch content and low seed oil content in chickpea. The above results may be used to improve chickpea seed oil content in two ways. One is to edit to co-express with oil synthesis-related genes, which may increase carbon metabolites flowing to oil synthesis, and another is to increase the expression levels of miRNA159 and miRNA319 to inhibit the expression of , which may downregulate starch synthesis-related genes, making more carbon metabolites flow into oil synthesis. Our study will provide a basis for future breeding efforts to increase the oil content of chickpea seeds.
大豆的种子油和淀粉含量与鹰嘴豆有显著差异。然而，关于其分子机制的研究有限。为了解决这个问题，我们对物种特异性基因以及与酰基脂质、淀粉和碳代谢相关的基因进行了综合转录组学和生物信息学分析。在大豆特异性基因的七种表达模式中，有四种在油脂积累的中后期高度表达；这些基因显著富集脂肪酸合成和碳代谢，并且与在大豆种子发育中期高度表达的常见乙酰辅酶A羧化酶（ACCase）一起，常见的淀粉降解酶β-淀粉酶-5（BAM5）在大豆种子发育早期高度表达，且油脂合成相关基因（）与（）共表达，这可能导致大豆种子油含量高而种子淀粉含量低。常见的ADP-葡萄糖焦磷酸化酶（AGPase）在鹰嘴豆种子发育中期高度表达，与大豆相比，鹰嘴豆中有更多淀粉生物合成基因与四个转录因子同源基因共表达，并且常见的WRI1在鹰嘴豆中不与油脂合成基因共表达，这可能导致鹰嘴豆种子淀粉含量高而种子油含量低。上述结果可用于通过两种方式提高鹰嘴豆种子油含量。一种是编辑（）使其与油脂合成相关基因共表达，这可能会增加流向油脂合成的碳代谢物，另一种是提高miRNA159和miRNA319的表达水平以抑制（）的表达，这可能会下调淀粉合成相关基因，使更多碳代谢物流入油脂合成。我们的研究将为未来提高鹰嘴豆种子油含量的育种工作提供依据。
