Ca2+ mediates transcription factor PuDof2.5 and suppresses stone cell production in pear fruits

• Published in: Frontiers in plant science Vol. 13; p. 976977
• Main Authors: Zhang, He, Gao, Siyang, Wang, Tianye, Xu, Mingyang, Li, Xinyue, Du, Guodong
• Format: Journal Article
• Language: English
• Published: Frontiers Media S.A 24.08.2022
• Subjects: Ca2; lignin; pear; Plant Science; PuDof2.5; PuPRX42-like; stone cell
• ISSN: 1664-462X; 1664-462X
• DOI: 10.3389/fpls.2022.976977

Stone cells are sclerenchyma cells formed by deposition of lignin, which is the most significant factor limiting the quality of pears. Ca 2+ was known to inhibit stone cells in pear fruits, but the underlying molecular mechanism remains unclear. Our study revealed that exogenous CaCl 2 (Ca 2+ ) treatment of “Nanguo” pear ( Pyrus ussuriensis ) suppressed the synthesis of lignin and stone cell production. We further analysed the transcriptomes using RNA-seq, identified a transcription factor, PuDof2.5 , and its targets gene PuPRX42-like (lignin polymerase gene) expression decreased in CaCl 2 -treated samples, which are involved in suppressing lignin biosynthesis in pear fruit. PuDof2.5 was found to bind directly to the PuPRX42-like promoter and induced its transcription. Taken together, our results revealed that Ca 2+ modulated the key lignin biosynthetic transcription factor PuDof2.5 to suppress stone cell production in pear fruits.