Glycine max histone demethylase-LDL2 regulates flowering time via FERONIA for regional adaptation (PRJCA031230)

Flowering at the appropriate time is one of the critical traits to determine regional adaptation, yield, and quality of crops including soybean. Although several genes of flowering time regulation have been identified in soybeans, the epigenetic regulators are still largely unknown. Here, we performed a forward genetic screen to identify a soybean mutant with an early flowering phenotype (ef1). We further cloned the gene (designated as GmLDL2) that encodes an ortholog of the lysine-specific demethylase like 2 (LDL2) in Arabidopsis. In vitro and in vivo enzymatic activity analysis demonstrated that GmLDL2 has a demethylase activity towards H3K4me1 and H3K4me2. Integrative ChIP-seq and RNA-seq analyses identified a GmLDL2-mediated gene GmFER, an ortholog of FERONIA in Arabidopsis by modification of histone level at the locus. Consistently, genetic analyses provide evidence that GmFER is a positive regulator of flowering in soybeans.