SPL3/4/5 Integrate Developmental Aging and Photoperiodic Signals into the FT-FD Module in Arabidopsis Flowering  

作　　者：Jae-Hoon Jung Hyo-Jun Lee Jae Yong Ryu Chung-Mo Park 

机构地区：[1]Sainsbury Laboratory, University of Cambridge, Cambridge CB2 1LR, UK [2]Department of Chemistry [3]plant Genomics and Breeding Institute Seoul National University, Seou1151-742, Korea [4]These authors contributed equally to this article

出　　处：《Molecular Plant》2016年第12期1647-1659,共13页分子植物（英文版）

摘　　要：Environmental sensitivity varies across developmental phases in flowering plants. In the juvenile phase, mi- croRNA156 （miR156）-mediated repression of SQUAMOSA PROMOTER-BINDING PROTEIN-LIKE （SPL） transcription factors renders Arabidopsis plants incompetent to floral inductive signals, including long- day （LD） photoperiod. During the vegetative phase transition, which accompanies a reduction of miR156 and a concomitant elevation of its targets, plants acquire reproductive competence such that LD signals promote flowering. However, it remains largely unknown how developmental signals are associated with photoperiodic flowering. Here, we show that SPL3, SPL4, and SPL5 （SPL3/4/5） potentiate the FLOWERING LOCUS T （FT）-FD module in photoperiodic flowering. SPL3/4/5 function as transcriptional activators through the interaction with FD, a basic leucine zipper transcription factor which plays a critical role in photoperiodic flowering. SPL3/4/5 can directly bind to the promoters of APETALA1, LEAFY, and FRUITFULL, thus mediating their activation by the FT-FD complex. Our findings demonstrate that SPL3/ 4/5 act synergistically with the FT-FD module to induce flowering under LDs, providing a long-sought mo- lecular knob that links developmental aging and photoperiodic flowering.Environmental sensitivity varies across developmental phases in flowering plants. In the juvenile phase, mi- croRNA156 （miR156）-mediated repression of SQUAMOSA PROMOTER-BINDING PROTEIN-LIKE （SPL） transcription factors renders Arabidopsis plants incompetent to floral inductive signals, including long- day （LD） photoperiod. During the vegetative phase transition, which accompanies a reduction of miR156 and a concomitant elevation of its targets, plants acquire reproductive competence such that LD signals promote flowering. However, it remains largely unknown how developmental signals are associated with photoperiodic flowering. Here, we show that SPL3, SPL4, and SPL5 （SPL3/4/5） potentiate the FLOWERING LOCUS T （FT）-FD module in photoperiodic flowering. SPL3/4/5 function as transcriptional activators through the interaction with FD, a basic leucine zipper transcription factor which plays a critical role in photoperiodic flowering. SPL3/4/5 can directly bind to the promoters of APETALA1, LEAFY, and FRUITFULL, thus mediating their activation by the FT-FD complex. Our findings demonstrate that SPL3/ 4/5 act synergistically with the FT-FD module to induce flowering under LDs, providing a long-sought mo- lecular knob that links developmental aging and photoperiodic flowering.

关 键 词：photoperiodic flowering developmental aging SPL transcription factors FT-FD complex 

分 类 号：Q11[生物学—普通生物学] S68[农业科学—观赏园艺]