An alternative splicing variant of PtRD26 delays leaf senescence by regulating multiple NAC transcription factors in Populus

编号 040030303

推送时间 20210809

研究领域 森林培育 

年份 2021 

类型 期刊 

语种 英语

标题 An alternative splicing variant of PtRD26 delays leaf senescence by regulating multiple NAC transcription factors in Populus

来源期刊 The Plant Cell

期 第303期

发表时间 20210206

关键词 Populus;  leaf senescence;  RNA;  Sen-NAC TFs;  PtRD26IR; 

摘要 During leaf senescence, the final stage of leaf development, nutrients are recycled from leaves to other organs, and therefore proper control of senescence is thus critical for plant fitness. Although substantial progress has been achieved in understanding leaf senescence in annual plants, the molecular factors that control leaf senescence in perennial woody plants are largely unknown. Using RNA sequencing, we obtained a high-resolution temporal profile of gene expression during autumn leaf senescence in poplar (Populus tomentosa). Identification of hub transcription factors (TFs) by co-expression network analysis of genes revealed that senescence-associated NAC family TFs (Sen-NAC TFs) regulate autumn leaf senescence. Age-dependent alternative splicing (AS) caused an intron retention (IR) event in the pre-mRNA encoding PtRD26, a NAC-TF. This produced a truncated protein PtRD26IR, which functions as a dominant-negative regulator of senescence by interacting with multiple hub Sen-NAC TFs, thereby repressing their DNA-binding activities. Functional analysis of senescence-associated splicing factors identified two U2 auxiliary factors that are involved in AS of PtRD26IR. Correspondingly, silencing of these factors decreased PtRD26IR transcript abundance and induced early senescence. We propose that an age-dependent increase of IR splice variants derived from Sen-NAC TFs is a regulatory program to fine tune the molecular mechanisms that regulate leaf senescence in trees.

服务人员 孙小满

服务院士 尹伟伦

PDF文件 浏览全文