Abstract
BackgroundFlowering time is a key trait for regional adaption and seed production in rice (Oryza sativa L.). Forward and reverse genetic studies have characterized a number of flowering-time genes. However, co-expression analysis has not been used to identify the flowering-time genes.ResultsWe predicted a G2-like family transcription factor, OsPHL3, by co-expression networks analysis with photoperiodic flowering pathway genes. OsPHL3 contains a MYB-CC domain, and was localized in the nucleus with transcriptional activation potential. OsPHL3 was mainly expressed in the leaves and exhibited a circadian rhythmic expression pattern. Rice lines overexpressing OsPHL3 showed a delayed flowering time in the genetic background of TP309 under both long-day (Beijing) and short-day (Hainan) conditions. By contrast, the knockout rice lines of OsPHL3 by CRISPR/Cas9 technology promoted flowering time regardless of genetic backgrounds (i.e. Nipponbare and TP309) or day length. Further analysis indicated that OsPHL3 delayed flowering time by down-regulating the expression of Hd3a and RFT1 through promoting Hd1 under long-day conditions (LDs), or suppressing Ehd1/Hd1 under short-day conditions (SDs).ConclusionsOur results suggested that co-expression analysis is a useful strategy for identifying novel flowering-time genes in rice.
Highlights
Flowering time is a key trait for regional adaption and seed production in rice (Oryza sativa L.)
For the Ghd7-Ehd1-Heading date 3a (Hd3a)/RICE FLOWERING LOCUS T 1 (RFT1) pathway that is unique to rice, Grain number, plant height, and heading date 7 (Ghd7) acts as upstream of Early heading date1 (Ehd1), which does not have an ortholog in Arabidopsis
Gene co-expression analysis identified G2-like family transcription factors involving in flowering time pathway in rice In plants, leaves perceive information of day-length and temperature changes, which was subsequently used to determine flowering time [31, 32]
Summary
Flowering time is a key trait for regional adaption and seed production in rice (Oryza sativa L.). Flowering time is one of the most important agronomic traits in determining grain yield and regional adaptation [1,2,3]. The first one is OsGI-Hd1-Hd3a pathway [4,5,6], which is conserved between Arabidopsis thaliana and rice [7]. The rice OsGI-Hd1-Hd3a pathway has a one to one correspondence with Arabidopsis GIGANTEA (GI) – CONSTANS (CO) - FLOWERING LOCUS T (FT) [7]. For the Ghd7-Ehd1-Hd3a/RFT1 pathway that is unique to rice, Grain number, plant height, and heading date 7 (Ghd7) acts as upstream of Early heading date (Ehd1), which does not have an ortholog in Arabidopsis
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.
