Abstract
BackgroundGrain 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.ResultsHere, 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.ConclusionsTaken 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.
Highlights
Grain size is one of the key agronomic traits that impact grain yield
OsCYP20–2 Regulates Grain Size and Inflorescence Architecture We previously reported that CYP20–2 regulated plant height and chilling tolerance in rice (Ge et al 2020)
We found that the mutation of OsCYP20–2 reduced grain length, while brown grain width and thickness were unchanged (Fig. 1a-c)
Summary
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. Genetic and molecular analyses have identified numerous quantitative trait loci (QTLs) and genes involved in multiple signaling pathways that regulate grain size. The prolyl cis-trans isomerization functions as a molecular switch to regulate protein conformation. This prolyl cis-trans conversion can be catalyzed by peptidyl prolyl cis-trans isomerase (PPIase). OsCYP20–2 functions with OsFSD2 to scavenge reactive oxygen species (ROS) in chloroplasts, and the nuclear-localized variant OsNuCYP20–2 targets SLENDER RICE1 to regulate GA signaling (Ge et al 2020). It remains unknown if CYPs regulate grain size by other mechanisms
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
