摘要
Pumilio RNAbindingproteinsparticipateinmes-senger RNA(mRNA)degradation and t ranslational repression,but their roles in plant development are largely unclear.Here,we show that Arabidopsis PUMILIO PROTEIN24(APUM24),an atypical Pumiliohomology domaincontaining protein,plays an im-portant part in regulating seed maturation,a major stage of plant development.APUM24 is strongly expressed in maturing seeds.Reducing APUM24 expression resulted in abnormal seed maturation,wrinkled seeds,and lower seed oil contents,and APUM24 knockdown resulted in lower levels of WRINKLED 1(WRI1),a key transcription factor con-trolling seed oil accumulation,and lower expression of WRI1 target genes.APUM24 reduces the mRNA stability of BTB/POZMATH(BPM)family genes,thus decreasing BPM protein levels.BPM is responsible for the 26S proteasomemediated degradation of WRI1 and has important functions in plant growth and development.The 3′untranslated regions of BPM family genes contain putative Pumilio response elements(PREs),which are bound by APUM24.Re-duced BPM or increased WRI1 expression rescued the decient seed maturation of apum242 knock-down mutants,and APUM24 overexpression re-sulted in increased seed size and weight.Therefore,APUM24 is crucial to seed maturation through its action as a positive regulatornetuning the BPMWRI1 module,making APUM24 apromising target for breeding strategies to increase crop yields.
基金
supported by the National Natural Science Foundation of China(31870301,31370350 for S.Z.,31871222 for C.Y.)
the Guangdong Province Universities and Colleges Pearl River Scholar Funded Scheme(2016 for S.Z.)
the award from the Program for Changjiang Scholars(2017 for C.Y.).
