BR signal influences Arabidopsis ovule and seed number through regulating related genes expression by BZR1.
Ovule and seed developments are crucial processes during plant growth, which are affected by different signaling pathways. In this paper, we demonstrate that the brassinosteroid (BR) signal is involved in ovule initiation and development. Ovule and seed numbers are significantly different when comparing BR-related mutants to wild-type controls. Detailed observation indicates that BR regulates the expression level of genes related to ovule development, including HLL, ANT, and AP2, either directly by targeting the promoter sequences or indirectly via regulation by BR-induced transcription factor BZR1. Also, Western blot demonstrates that the dephosphorylation level of BZR1 is consistent with ovule and seed number. The intragenic bzr1-1D suppressors bzs247 and bzs248 have much fewer ovules and seeds than bzr1-1D, which are similar to wild-type, suggesting that the phenotype can be rescued. The molecular and genetic experiments confirm that BZR1 and AP2 probably affect Arabidopsis ovule number determination antagonistically.
Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
Hui-Ya
HY
Huang
Wen-Bo
WB
Jiang
Yu-Wei
YW
Hu
Ping
P
Wu
Jia-Ying
JY
Zhu
Wan-Qi
WQ
Liang
Zhi-Yong
ZY
Wang
Wen-Hui
WH
Lin
D017360:Arabidopsis / Q000166:cytology / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D060406:Brassinosteroids / Q000378:metabolism*; D004268:DNA-Binding Proteins; D018506:Gene Expression Regulation, Plant; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism; D009154:Mutation; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D056771:Ovule / Q000254:growth & development*; D010641:Phenotype; D010766:Phosphorylation; D012639:Seeds / Q000254:growth & development*; D015398:Signal Transduction
C499534:APETALA2 protein, Arabidopsis; D029681:Arabidopsis Proteins; C454444:BZR1 protein, Arabidopsis; D060406:Brassinosteroids; D004268:DNA-Binding Proteins; D018398:Homeodomain Proteins; D009687:Nuclear Proteins