Functional analyses of the flowering time gene OsMADS50, the putative SUPPRESSOR OF OVEREXPRESSION OF CO 1/AGAMOUS-LIKE 20 (SOC1/AGL20) ortholog in rice.
A late-flowering mutant was isolated from rice T-DNA-tagging lines. T-DNA had been integrated into the K-box region of Oryza sativa MADS50 (OsMADS50), which shares 50.6% amino acid identity with the Arabidopsis MADS-box gene SUPPRESSOR OF OVEREXPRESSION OF CO 1/AGAMOUS-LIKE 20 (SOC1/AGL20). While overexpression of OsMADS50 caused extremely early flowering at the callus stage, OsMADS50 RNAi plants exhibited phenotypes of late flowering and an increase in the number of elongated internodes. This confirmed that the phenotypes observed in the knockout (KO) plants are because of the mutation in OsMADS50. RT-PCR analyses of the OsMADS50 KO and ubiquitin (ubi):OsMADS50 plants showed that OsMADS50 is an upstream regulator of OsMADS1, OsMADS14, OsMADS15, OsMADS18, and Hd (Heading date)3a, but works either parallel with or downstream of Hd1 and O. sativa GIGANTEA (OsGI). These results suggest that OsMADS50 is an important flowering activator that controls various floral regulators in rice.
Lee
Shinyoung
S
National Research Laboratory of Plant Functional Genomics, Division of Molecular and Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang 790-784, Korea.
Kim
Joonyul
J
Han
Jong-Jin
JJ
Han
Min-Jung
MJ
An
Gynheung
G
D001483:Base Sequence; D017931:DNA Primers; D035264:Flowers / Q000235:genetics*; D017353:Gene Deletion; D026161:MADS Domain Proteins / Q000235:genetics*; D012275:Oryza / Q000235:genetics; D010940:Plant Proteins / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction
D017931:DNA Primers; D026161:MADS Domain Proteins; D010940:Plant Proteins