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

He Zhang; Siyang Gao; Tianye Wang; Mingyang Xu; Xinyue Li; Guodong Du

doi:10.3389/fpls.2022.976977

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

Front Plant Sci. 2022 Aug 24:13:976977. doi: 10.3389/fpls.2022.976977. eCollection 2022.

Authors

He Zhang¹, Siyang Gao¹, Tianye Wang², Mingyang Xu¹, Xinyue Li¹, Guodong Du¹

Affiliations

¹ Key Laboratory of Fruit Postharvest Biology, Liaoning Province, College of Horticulture, Shenyang Agricultural University, Shenyang, China.
² General Station of Agricultural Technology Extension, Xinjiang Production and Construction Corps, Urumqi, China.

Abstract

Stone cells are sclerenchyma cells formed by deposition of lignin, which is the most significant factor limiting the quality of pears. Ca²⁺ was known to inhibit stone cells in pear fruits, but the underlying molecular mechanism remains unclear. Our study revealed that exogenous CaCl₂ (Ca²⁺) 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 CaCl₂-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 Ca²⁺ modulated the key lignin biosynthetic transcription factor PuDof2.5 to suppress stone cell production in pear fruits.

Keywords: Ca2+; PuDof2.5; PuPRX42-like; lignin; pear; stone cell.