Shams Mohamad Reza, Razvi Khadige, Rahnama Hassan, Dashchi Sahar, Mirzaii Hossein Hadavand
Agricultural Biotechnology Research Institute of Iran (ABRII), Agricultural Research Education and Extension Organization (AREEO), Karaj, Iran.
National Institute of Genetic Engineering and Biotechnology (NIGEB), Tehran, Iran.
Plant Cell Rep. 2025 Jul 1;44(7):163. doi: 10.1007/s00299-025-03554-2.
WRI1 and LPAAT gene overexpression enhances oil content and seed weight in tobacco plants, indicating potential candidate genes for enhancing seed oil in transgenic oil seed crops. The boosting triacylglycerols (TAG) assembly reactions (pull), the increasing fatty acid (FA) production (push), and the combination of these strategies were used to enhance seed oil content in transgenic tobacco plants. Three lines containing WRINKLED1 (WRI) (A1, A2, A7), two lines containing Lysophosphatidic Acid Acyltransferase (LPAAT) (B2, B3), and two lines containing WRI + LPAAT (AB1, AB2) transgenes were grown in greenhouse conditions and their T3 generations were used for further analysis. Total seed oil content in transgenic plants significantly increased within the range of 23.92-41%, respectively, in B3 and A7 lines than the non-transgenic tobacco plants. In addition, significantly elevated soluble sugar contents within 103.33-136.05 mg/g DW and 88.85-114.3 mg/g DW were observed, respectively, in the leaves and seeds of transgenic lines compared to control plants. We suggested that the enhanced accumulations of total soluble sugar in the seeds and leaves contribute to reallocation of the photosynthetic precursors for enhanced oil synthesis in transgenic plants. Expression analysis of WRI1 and LPAAT genes in transgenic plants showed a weak positive correlation with oil content (r ≈ 0.42). Overexpression of WRI1 and LPAAT increased seed size and weight, potentially explaining oil accumulation due to increased seed weight. Finally, no synergistic effect was observed in the simultaneous expression of WRI1 and LPAAT genes, suggesting potential limitations in the availability of oil biosynthesis precursors and interactions with other genes. Meanwhile, these findings show that WRI1 and LPAAT are reliable targets for genetic transformation of oil seed crops for improvement their seed oil yield.
WRI1和LPAAT基因的过表达提高了烟草植株的含油量和种子重量，表明它们是提高转基因油料作物种子油含量的潜在候选基因。通过促进三酰甘油（TAG）组装反应（拉动）、增加脂肪酸（FA）产量（推动）以及将这些策略相结合，来提高转基因烟草植株的种子油含量。将含有皱叶1（WRI）的三个株系（A1、A2、A7）、含有溶血磷脂酸酰基转移酶（LPAAT）的两个株系（B2、B3）以及含有WRI + LPAAT的两个株系（AB1、AB2）在温室条件下种植，并使用它们的T3代进行进一步分析。与非转基因烟草植株相比，转基因植株的总种子油含量在B3和A7株系中分别显著增加了23.92 - 41%。此外，与对照植株相比，在转基因株系的叶片和种子中分别观察到可溶性糖含量显著升高，范围分别为103.33 - 136.05毫克/克干重和88.85 - 114.3毫克/克干重。我们认为，种子和叶片中总可溶性糖积累的增加有助于光合前体的重新分配，从而增强转基因植物中的油脂合成。转基因植物中WRI1和LPAAT基因的表达分析显示与油含量呈弱正相关（r≈0.42）。WRI1和LPAAT的过表达增加了种子大小和重量，这可能解释了由于种子重量增加导致的油脂积累。最后，在WRI1和LPAAT基因同时表达时未观察到协同效应，这表明油脂生物合成前体的可用性以及与其他基因的相互作用可能存在潜在限制。同时，这些发现表明WRI1和LPAAT是用于遗传转化油料作物以提高其种子油产量的可靠靶点。
