Histone Acetyltransferase GCN5 Contributes to Stem Cuticular Wax Biosynthesis by Acetylating ECERIFERUM 3 (CER3) in Arabidopsis thaliana

Cuticular wax is a major composition of plant surface cuticle, which exerts crucial functions in optimizing plant growth. Histone acetylation regulates gene expression of diverse biological processes, but little is known about its role in cuticular wax synthesis. Here we observed that mutation of Arabidopsis histone acetyltransferase GCN5 gene impaired stem cuticular wax accumulation. Furthermore, three target genes of GCN5 (CER3, CER26 and CER1-L1) were identified by RNA-Seq and ChIP assays. Consistently, H3K9/14 acetylation levels in promoter regions of CER3, CER26 and CER1-L1 were significantly decreased in gcn5 as compared to wild type. Notably, overexpression of CER3 in the gcn5 mutant restored the stem cuticular wax accumulation. Collectively, these data demonstrate that Arabidopsis GCN5 is involved in stem cuticular wax accumulation by modulating CER3 expression via H3K9/14 acetylation, which present evidence that histone acetylation plays an important role in cuticular wax biosynthesis

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