State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agricultural University, Guangzhou, China.
College of Life Sciences, South China Agricultural University, Guangzhou, China.
Physiol Plant. 2022 May;174(3):e13692. doi: 10.1111/ppl.13692.
Improving the grain yield of rice is a central goal of basic and applied scientific research. Here, we identified an anion transporter, OsAT1, localized in the endoplasmic reticulum and Golgi. OsAT1 is highly expressed in flag, stem, and sheath as monitored using qRT-PCR and pOsAT1::GUS. Thousand-grain weight, grain weight per plant, and content of starch were significantly increased in OsAT1 knock-down mutants (OsAT1-Ri) but significantly decreased in OsAT1 overexpressed lines (OsAT1-OE). In addition, the grain weight per plant increased by 6.17% to 6.78% in OsAT1-RNAi lines, whereas it decreased by 45.93% to 46.76% in OsAT1-OE lines, compared to wild-type. Moreover, the copper content was noticeably reduced in flag leaf of OsAT1-Ri lines and increased in OsAT1-OE lines. RNA-sequencing analysis of OsAT1-OE lines revealed that the genes related to starch biosynthesis and metabolism pathway were enriched in the down-regulated category. Thus, our results suggest that knock-down of OsAT1 in rice possibly reduces copper accumulation and improves the accumulation of storage starch, hence, increasing the grain size and weight. OsAT1 may be a useful gene to consider for cereal breeding programs.
提高水稻的谷物产量是基础和应用科学研究的核心目标。在这里，我们鉴定了一个阴离子转运蛋白 OsAT1，其定位于内质网和高尔基体。通过 qRT-PCR 和 pOsAT1::GUS 监测，OsAT1 在旗叶、茎和叶鞘中高度表达。千粒重、每株粒重和淀粉含量在 OsAT1 敲低突变体（OsAT1-Ri）中显著增加，但在 OsAT1 过表达系（OsAT1-OE）中显著降低。此外，与野生型相比，OsAT1-RNAi 系的每株粒重增加了 6.17%至 6.78%，而 OsAT1-OE 系的每株粒重降低了 45.93%至 46.76%。此外，OsAT1-Ri 系旗叶中的铜含量明显降低，而 OsAT1-OE 系中的铜含量增加。OsAT1-OE 系的 RNA 测序分析表明，与淀粉生物合成和代谢途径相关的基因在下调类别中富集。因此，我们的结果表明，水稻中 OsAT1 的敲低可能会减少铜的积累并提高贮藏淀粉的积累，从而增加粒大小和重量。OsAT1 可能是谷物育种计划中一个有用的基因。
