Arabidopsis WRKY Transcription Factors WRKY12 and WRKY13 Oppositely Regulate Flowering under Short-Day Conditions.
In plants, photoperiod is an important cue for determining flowering. The floral transition in Arabidopsis thaliana is earlier under long-day (LD) than under short-day (SD) conditions. Flowering of Arabidopsis plants under SD conditions is mainly regulated by the plant hormone gibberellin (GA). Here, we report two WRKY transcription factors function oppositely in controlling flowering time under SD conditions. Phenotypic analysis showed that disruption of WRKY12 caused a delay in flowering, while loss of WRKY13 function promoted flowering. WRKY12 and WRKY13 displayed negatively correlated expression profiles and function successively to regulate flowering. Molecular and genetic analyses demonstrated that FRUITFULL (FUL) is a direct downstream target gene of WRKY12 and WRKY13. Interestingly, we found that DELLA proteins GIBBERELLIN INSENSITIVE (GAI) and RGA-LIKE1 (RGL1) interacted with WRKY12 and WRKY13, and their interactions interfered with the transcriptional activity of the WRKY12 and WRKY13. Further studies suggested thatWRKY12 and WRKY13 partly mediated the effect of GA3on controlling flowering time. Taken together, our results indicate that WRKY12 and WRKY13 oppositely modulate flowering time under SD conditions, which at least partially involves the action of GA.
Key Laboratory of Tropical Plant Resource and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, Yunnan 650223, China; Department of Biological and Environmental Engineering, Hefei University, Hefei, Anhui 230022, China; School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, China.
Wei
W
Li
Key Laboratory of Tropical Plant Resource and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, Yunnan 650223, China; University of Chinese Academy of Sciences, Beijing 100049, China.
Houping
H
Wang
Key Laboratory of Tropical Plant Resource and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, Yunnan 650223, China. Electronic address: ydq@xtbg.ac.cn.
Diqiu
D
Yu
D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development / Q000378:metabolism* / Q000528:radiation effects; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D035264:Flowers / Q000254:growth & development* / Q000528:radiation effects; D018506:Gene Expression Regulation, Plant / Q000528:radiation effects; D026161:MADS Domain Proteins / Q000235:genetics; D017440:Photoperiod; D011401:Promoter Regions, Genetic / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic
D029681:Arabidopsis Proteins; D026161:MADS Domain Proteins; D012333:RNA, Messenger; D014157:Transcription Factors; C000624323:WRKY12 protein, Arabidopsis; C000605311:WRKY13 protein, Arabidopsis
DELLA proteins; FUL; WRKY transcription factor; flowering; gibberellin