The ripening of fleshy fruits is a complex, genetically programmed process that impacts fruit nutritional quality and shelf life. Based on the different ripening mechanisms, fruits are classified into two groups: climacteric (e.g. tomato, apple and banana) and non-climacteric (e.g. strawberry, grape, and citrus). Phytohormone ethylene is essential for the ripening of climacteric fruits, while the ripening of non-climacteric fruits is thought to be abscisic acid (ABA)-dependent.
A previous study has shown that mRNA mA methylation, which is considered as an mRNA “epitranscriptome”, participates in the ripening control of climacteric fruit tomato. However, whether mA is evolutionarily conserved among different types of fruits has not been defined. Moreover, the regulatory function of mA in ripening of non-climacteric fruits remains elusive.
In a study published in Genome Biology, the same research group led by Dr. QIN Guozheng from Institute of Botany, Chinese Academy of Sciences (IBCAS) demonstrated that mA methylation regulates the ripening of strawberry, a classical non-climacteric fruit, by targeting ABA pathway.
The researchers found that mA methylation displays a dramatic change at ripening onset of strawberry. The mA modification in the coding sequence (CDS) regions appears to be ripening-specific and tends to stabilize the mRNAs, whereas mA around the stop codons and within the 3’ untranslated regions is generally negatively correlated with the abundance of the mRNAs.
Researchers identified thousands of transcripts with mA hypermethylation in the CDS regions, including those of NCED5, ABAR, and AREB1 in the abscisic acid (ABA) biosynthesis and signaling pathway.
Further analysis demonstrated that the methyltransferases MTA and MTB are indispensable for normal ripening of strawberry fruit, and MTA-mediated mA modification promotes mRNA stability of NCED5 and AREB1, while facilitates translation of ABAR.
“This work reveals a regulatory role of mA methylation on the ripening of the non-climacteric strawberry fruit. These findings provide new insights into understanding the regulatory networks controlling fruit ripening,” said Prof. QIN Guozheng, the correspondence author.
This study was funded by the National Key Research and Development Program of China and the National Natural Science Foundation of China.
Representative images of octoploid cultivated strawberry fruit at various developmental stages (Image by IBCAS)
Article link: https://rdcu.be/clPZr
Contact:
Email: gzqin@ibcas.ac.cn
Institute of Botany, Chinese Academy of Sciences
The ripening of fleshy fruits is a complex, genetically programmed process that impacts fruit nutritional quality and shelf life. Based on the different ripening mechanisms, fruits are classified into two groups: climacteric (e.g. tomato, apple and banana) and non-climacteric (e.g. strawberry, grape, and citrus). Phytohormone ethylene is essential for the ripening of climacteric fruits, while the ripening of non-climacteric fruits is thought to be abscisic acid (ABA)-dependent.
A previous study has shown that mRNA mA methylation, which is considered as an mRNA “epitranscriptome”, participates in the ripening control of climacteric fruit tomato. However, whether mA is evolutionarily conserved among different types of fruits has not been defined. Moreover, the regulatory function of mA in ripening of non-climacteric fruits remains elusive.
In a study published in Genome Biology, the same research group led by Dr. QIN Guozheng from Institute of Botany, Chinese Academy of Sciences (IBCAS) demonstrated that mA methylation regulates the ripening of strawberry, a classical non-climacteric fruit, by targeting ABA pathway.
The researchers found that mA methylation displays a dramatic change at ripening onset of strawberry. The mA modification in the coding sequence (CDS) regions appears to be ripening-specific and tends to stabilize the mRNAs, whereas mA around the stop codons and within the 3’ untranslated regions is generally negatively correlated with the abundance of the mRNAs.
Researchers identified thousands of transcripts with mA hypermethylation in the CDS regions, including those of NCED5, ABAR, and AREB1 in the abscisic acid (ABA) biosynthesis and signaling pathway.
Further analysis demonstrated that the methyltransferases MTA and MTB are indispensable for normal ripening of strawberry fruit, and MTA-mediated mA modification promotes mRNA stability of NCED5 and AREB1, while facilitates translation of ABAR.
“This work reveals a regulatory role of mA methylation on the ripening of the non-climacteric strawberry fruit. These findings provide new insights into understanding the regulatory networks controlling fruit ripening,” said Prof. QIN Guozheng, the correspondence author.
This study was funded by the National Key Research and Development Program of China and the National Natural Science Foundation of China.
Representative images of octoploid cultivated strawberry fruit at various developmental stages (Image by IBCAS)
Article link: https://rdcu.be/clPZr
Contact:
Email: gzqin@ibcas.ac.cn
Institute of Botany, Chinese Academy of Sciences