复制与转录的碱基配对，Phytol:OsbZIP72和OsMYBS2反向协同调控OsPsbS1在水稻中转录

小君 2023-01-30 15:08:16 89

复制与转录的碱基配对，Phytol:OsbZIP72和OsMYBS2反向协同调控OsPsbS1在水稻中转录https://nph.onlinelibrary.wiley.com/doi/abs/10.1111/nph.16877?af=RLinksHere we demonstrated that the expression of OsPsbS1 is directly up‐regulated by OsbZIP72 while repressed by OsMYBS2 in rice. We identified a new cis‐element GACAGGTG in japonica OsPsbS1 promoter to which OsbZIP72 could strongly bind and activate the expression of OsPsbS1. The new cis‐element CTAATC confers specific binding for

复制与转录的碱基配对，Phytol:OsbZIP72和OsMYBS2反向协同调控OsPsbS1在水稻中转录(1)

非光化学猝灭(NPQ)是一种复杂的光保护过程，在维持植物适应性方面起着重要作用。PsbS 蛋白是快速诱导 NPQ 所必需的，并且在叶片中以剂量依赖的方式发挥作用。然而，在陆地植物中，psb 的转录控制却鲜为人知。

这里我们证明 OsbZIP72直接上调 osspsbs1的表达，而 OsbZIP72则抑制 ossmybs2的表达。我们在粳稻 OsPsbS1启动子中发现了一个新的顺式元件 GACAGGTG，OsbZIP72能与其结合并激活 OsPsbS1的表达。新的顺式元件 CTAATC 在粳稻 OsPsbS1启动子中与 OsMYBS2特异性结合。OsbZIP72可被 SAPK1激活，并依赖 ABA 信号通路发挥作用。GF14A 蛋白通过调节核细胞穿梭来影响 OsMYBS2的阻遏活性，而 Ser53是 OsMYBS2保持在细胞质中的必要条件。OsbZIP72基因敲除系在强光条件下诱导 osspsbs1转录的能力受到很大的影响，而 ossmybs2基因敲除系在弱光条件下对 osspsbs1转录的抑制则明显减弱。这些结果揭示了 NPQ 过程、 ABA 信号转导途径和非生物胁迫信号转导途径之间的相互作用。这些复杂的机制可能有助于提高水稻的光保护作用和光合作用。

Nonphotochemical quenching (NPQ) an intricate photoprotective process plays fundamental roles in maintaining plant fitness. The PsbS protein is essential for the rapid induction of NPQ and acts in a dose‐dependent manner in leaves. However little is known on the transcriptional control of PsbS in land plants.

Here we demonstrated that the expression of OsPsbS1 is directly up‐regulated by OsbZIP72 while repressed by OsMYBS2 in rice. We identified a new cis‐element GACAGGTG in japonica OsPsbS1 promoter to which OsbZIP72 could strongly bind and activate the expression of OsPsbS1. The new cis‐element CTAATC confers specific binding for OsMYBS2 in japonica OsPsbS1 promoter.

OsbZIP72 can be activated by SAPK1 and acts depending on the ABA signaling pathway. GF14A protein affects the repression activity of OsMYBS2 by regulating its nucleocytoplasmic shuttling and the Ser53 is necessary for OsMYBS2 to be retained in the cytoplasm. The inducibility of OsPsbS1 transcription under high‐light condition in OsbZIP72 knockout lines was greatly impaired while the repression of OsPsbS1 transcription under low‐light environment in OsMYBS2 knockout lines was significantly alleviated.

These results reveal cross‐talks among NPQ process ABA signaling pathway and abiotic stress signaling. The elaborate mechanisms may help enhance photoprotection and improve photosynthesis in rice.

Links

https://nph.onlinelibrary.wiley.com/doi/abs/10.1111/nph.16877?af=R

复制与转录的碱基配对，Phytol:OsbZIP72和OsMYBS2反向协同调控OsPsbS1在水稻中转录(2)