title: The Banana Transcriptional Repressor MaDEAR1 Negatively Regulates Cell Wall-Modifying Genes Involved in Fruit Ripening.
abstract: Ethylene plays an essential role in many biological processes including fruit ripening via modulation of ethylene signaling pathway. Ethylene Response Factors (ERFs) are key transcription factors (TFs) involved in ethylene perception and are divided into AP2, RAV, ERF, and DREB sub-families. Although a number of studies have implicated the involvement of DREB sub-family genes in stress responses, little is known about their roles in fruit ripening. In this study, we identified a DREB TF with a EAR motif, designated as MaDEAR1, which is a nucleus-localized transcriptional repressor. Expression analysis indicated that MaDEAR1 expression was repressed by ethylene, with reduced levels of histone H3 and H4 acetylation at its regulatory regions during fruit ripening. In addition, MaDEAR1 promoter activity was also suppressed in response to ethylene treatment. More importantly, MaDEAR1 directly binds to the DRE/CRT motifs in promoters of several cell wall-modifying genes including MaEXP1/3, MaPG1, MaXTH10, MaPL3, and MaPME3 associated with fruit softening during ripening and represses their activities. These data suggest that MaDEAR1 acts as a transcriptional repressor of cell wall-modifying genes, and may be negatively involved in ethylene-mediated ripening of banana fruit. Our findings provide new insights into the involvement of DREB TFs in the regulation of fruit ripening.
authors.affiliation: State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Key Laboratory for Postharvest Science, College of Horticultural Science, South China Agricultural University Guangzhou, China.
authors.forename: Zhong-Qi
authors.initials: ZQ
authors.lastname: Fan
authors.affiliation: State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Key Laboratory for Postharvest Science, College of Horticultural Science, South China Agricultural University Guangzhou, China.
authors.forename: Jian-Fei
authors.initials: JF
authors.lastname: Kuang
authors.affiliation: State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Key Laboratory for Postharvest Science, College of Horticultural Science, South China Agricultural University Guangzhou, China.
authors.forename: Chang-Chun
authors.initials: CC
authors.lastname: Fu
authors.affiliation: State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Key Laboratory for Postharvest Science, College of Horticultural Science, South China Agricultural University Guangzhou, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Shan
authors.affiliation: State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Key Laboratory for Postharvest Science, College of Horticultural Science, South China Agricultural University Guangzhou, China.
authors.forename: Yan-Chao
authors.initials: YC
authors.lastname: Han
authors.affiliation: State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Key Laboratory for Postharvest Science, College of Horticultural Science, South China Agricultural University Guangzhou, China.
authors.forename: Yun-Yi
authors.initials: YY
authors.lastname: Xiao
authors.affiliation: State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Key Laboratory for Postharvest Science, College of Horticultural Science, South China Agricultural University Guangzhou, China.
authors.forename: Yu-Jie
authors.initials: YJ
authors.lastname: Ye
authors.affiliation: State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Key Laboratory for Postharvest Science, College of Horticultural Science, South China Agricultural University Guangzhou, China.
authors.forename: Wang-Jin
authors.initials: WJ
authors.lastname: Lu
authors.affiliation: Sugar Research Australia, Brisbane QLD, Australia.
authors.forename: Prakash
authors.initials: P
authors.lastname: Lakshmanan
authors.affiliation: Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences Guangzhou, China.
authors.forename: Xue-Wu
authors.initials: XW
authors.lastname: Duan
authors.affiliation: State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Key Laboratory for Postharvest Science, College of Horticultural Science, South China Agricultural University Guangzhou, China.
authors.forename: Jian-Ye
authors.initials: JY
authors.lastname: Chen
keywords: DREB; banana (Musa acuminata); cell wall modification; fruit ripening; transcriptional repression