The involvement of papaya CpSBP1 in modulating fruit softening and carotenoid accumulation by repressing CpPME1/2 and CpPDS4
The involvement of papaya CpSBP1 in modulating fruit softening and carotenoid accumulation by repressing CpPME1/2 and CpPDS4
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DOI：
10.1016/j.scienta.2019.108582
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发表时间：
2019-10-15
影响因子：
4.3
通讯作者：
Fu, Changchun
中科院分区：
文献类型：
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作者：
Han, Yanchao;Gao, Haiyan;Fu, Changchun
SQUAMOSA启动子结合蛋白（SBP）在果实成熟、花序分枝、赤霉素信号转导和花发育等许多重要的生物学过程中起着重要的作用。然而，SBPs参与番木瓜果实软化和类胡萝卜素积累的转录调控机制仍不清楚。本研究从番木瓜果实中克隆了一个SBP基因，命名为CpSBP 1。CpSBP 1在果实成熟过程中表达下调，表明其可能在转录水平上与番木瓜果实成熟有关。CpSBP 1是一个核蛋白，可与软化相关基因CpPME 1/2的启动子以及类胡萝卜素生物合成基因CpPDS 4结合。更重要的是，CpSBP 1是一种转录抑制因子，在体内可抑制CpPME 1/2和CpPDS 4的转录活性。这些结果表明，CpSBP 1可能通过调控CpPME 1/2和CpPDS 4参与番木瓜果实软化和类胡萝卜素积累，为进一步研究SBP转录因子在果实成熟中的调控机制奠定了基础。
SQUAMOSA promoter binding protein (SBP) plays important roles in many important biological processes, including fruit ripening, inflorescence branching, gibberellins signaling and flower development. Nevertheless, the transcriptional regulation mechanisms of SBPs involved in papaya fruit softening and carotenoid accumulation are still unknown. In this present study, a SBP gene, named as CpSBP1, was identified from papaya fruit. CpSBP1 was down-regulated during fruit ripening, indicating that it may be related to papaya fruit ripening at the transcriptional level. CpSBP1 was a nuclear protein and could bind to the promoters of soften-related genes CpPME1/2, as well as carotenoid biosynthesis gene CpPDS4. More importantly, CpSBP1 was a transcriptional repressor and could repress the transcriptional activities of CpPME1/2 and CpPDS4 in vivo. Collectively, these results suggest that CpSBP1 is involved in papaya fruit softening and carotenoid accumulation possibly through regulating CpPME1/2 and CpPDS4, expanding the knowledge of the regulation mechanisms of SBP transcription factor in fruit ripening.