PT - JOURNAL ARTICLE AU - Zhi Wang AU - Tianqing Zhu AU - Erqin Fan AU - Nan Lu AU - Fangqun Ouyang AU - Nan Wang AU - Guijuan Yang AU - Lisheng Kong AU - Guanzheng Qu AU - Shougong Zhang AU - Wenjun Ma AU - Junhui Wang TI - Potential function of <em>CbuSPL</em> and gene encoding its interacting protein during flowering in <em>Catalpa bungei</em> AID - 10.1101/803122 DP - 2019 Jan 01 TA - bioRxiv PG - 803122 4099 - http://biorxiv.org/content/early/2019/10/13/803122.short 4100 - http://biorxiv.org/content/early/2019/10/13/803122.full AB - “Bairihua”, a variety of the Catalpa bungei, has a large amount of flowers and a long flowering period which make it an excellent material for flowering researches in trees. SPL is one of the hub genes that regulate both flowering transition and development. Here, a SPL homologues CbuSPL9 was cloned using degenerate primers with RACE. Expression studies during flowering transition in Bairihua and ectopic expression in Arabidopsis showed that CbuSPL9 was functional similarly with its Arabidopsis homologues. In the next step, we used Y2H to identify the proteins that could interact with CbuSPL9. HMGA, an architectural transcriptional factor, was identified and cloned for further research. BiFC and BLI showed that CbuSPL9 could form a heterodimer with CbuHMGA in the nucleus. The expression analysis showed that CbuHMGA had a similar expression trend to that of CbuSPL9 during flowering in “Bairihua”. Intriguingly, ectopic expression of CbuHMGA in Arabidopsis would lead to aberrant flowers, but did not effect flowering time. Taken together, our results implied a novel pathway that ChuSPL9 regulated flowering development, but not flowering transition, with the participation of ChuHMGA. Further investments need to be done to verify the details of this pathway.