is a histone acetyltransferase that affects bolting development in Chinese flowering cabbage.

Histone acetylation is an important posttranslational modification associated with gene activation. In Arabidopsis, histone acetyltransferase 1 (HAC1) can promote flowering by regulating the transcription of , a major floral repressor. The size of the full-length cDNA and genomic DNA sequences of the histone acetyltransferase 1 gene () in Chinese flowering cabbage ( syn. ssp. var. ) were 5846 bp and 7376 bp, with an open reading frame (ORF) coding for a peptide with 1689 amino acids. The expression levels of in different tissues and different developmental stages were as follows: flower>leaf>stem>root, and completed bolting and flowering stage>5th true leaf-stage>4th true leaf-stage>3rd true leaf-stage>2nd true leaf-stage>1st true leaf-stage. Silencing of resulted in slow growth, and delayed bolting and flowering time in Chinese flowering cabbage. Molecular analysis showed that the mRNA level of was increased, indicating that the delayed flowering phenomenon was mediated by in the silenced group. In contrast, the expression levels of the autonomous-pathway genes were not significantly affected in the silenced group. In addition, the histone modification of chromatin was also not affected in the silenced group. is not the direct target gene of . However, may affect the bolting and flowering time of Chinese flowering cabbage through the epigenetic modification of upstream factors of .