A Cyclophilin OsCYP20–2 Interacts with OsSYF2 to Regulate Grain Length by Pre-mRNA Splicing

Abstract

Background Grain size is one of the key agronomic traits that impact grain yield. Several regulatory pathways had been reported to participate in grain size determination via cell expansion or proliferation in rice. However, little is known about cyclophilin and spliceosome participation in grain shape regulation. Results Here, we identified OsCYP20–2, a cyclophilin that influences spliceosome assembly to determine grain length. oscyp20–2 t1, a knock out mutant of OsCYP20–2 caused by T-DNA insertion, produced shorter grains with deficient cell elongation. Through yeast two-hybrid screening and pull-down assays, OsSYF2, a pre-mRNA splicing factor, was identified as an interacting protein of OsCYP20–2. The phenotypes of transgenic lines indicated that OsSYF2 positively regulates grain length via its influence on cell expansion. Transcriptomic analysis showed that OsSYF2 controls the expression and pre-mRNA alternative splicing of genes involved in sugar metabolism. In addition, these two genes have similar effects on panicle architecture. Conclusions Taken together, OsSYF2, an interacting protein of OsCYP20–2, controls grain length and panicle architecture by regulating the alternative splicing of pre-mRNA involved in cell elongation and sugar metabolism.

OsCyp2‐P, an auxin‐responsive cyclophilin, regulates Ca2+ calmodulin interaction for an ion‐mediated stress response in rice

“…RNA seq analysis of Cyclophilin A/DIAGEOTROPICA (DGT) in tomato (Ivanchenko et al, 2020) revealed the interplay between DGT, auxin, and PIN proteins responsible for root formation at various stages. The cyclophilin also influences grain size, as recently reported with the role of OsCYP20‐2 , which influences spliceosome assembly to determine the grain length (Ge, Tang, Luo, et al, 2020c). The oscyp20‐2 mutant has shorter grains with deficient cell elongation patterns.…”

Genome-wide identification and stress response analysis of cyclophilin gene family in apple (Malus × domestica)

“…LATERAL ROOTLESS2 is a cyclophilin protein that regulates lateral root initiation and auxin signaling pathway in rice [ 24 ]. OsCYP20-2 interacts with OsSYF2, a pre-mRNA splicing factor, and controls grain length and panicle architecture by regulating the alternative splicing of pre-mRNA involved in cell elongation and sugar metabolism [ 25 ]. These proteins can also regulate transcription.…”