Histone acetyltransferase general control non‐repressed protein 5 (GCN5) affects the fatty acid composition of Arabidopsis thaliana seeds by acetylating fatty acid desaturase3 (FAD3)

Abstract

Seed oils are important natural resources used in the processing and preparation of food. Histone modifications represent key epigenetic mechanisms that regulate gene expression, plant growth and development. However, histone modification events during fatty acid (FA) biosynthesis are not well understood. Here, we demonstrate that a mutation of the histone acetyltransferase GCN5 can decrease the ratio of α-linolenic acid (ALA) to linoleic acid (LA) in seed oil. Using RNA-Seq and ChIP assays, we identified FAD3, LACS2, LPP3 and PLAIIIβ as the targets of GCN5. Notably, the GCN5-dependent H3K9/14 acetylation of FAD3 determined the expression levels of FAD3 in Arabidopsis thaliana seeds, and the ratio of ALA/LA in the gcn5 mutant was rescued to the wild-type levels through the overexpression of FAD3. The results of this study indicated that GCN5 modulated FA biosynthesis by affecting the acetylation levels of FAD3. We provide evidence that histone acetylation is involved in FA biosynthesis in Arabidopsis seeds and might contribute to the optimization of the nutritional structure of edible oils through epigenetic engineering.

Enhancing microRNA167A expression in seed decreases the α‐linolenic acid content and increases seed size in Camelina sativa

“…However, there is limited information on transcriptional regulation of CsFAD3 in camelina. Previously it has been shown that in Arabidopsis FAD3 expression may be subject to various regulatory mechanisms including ones at the transcriptional level controlled by epigenetics (Wang et al ., ) and TFs (Mendes et al ., ). Here we demonstrate that microRNAs, which act as post‐transcriptional gene regulators of suites of genes, can be used to decipher a transcriptional mechanism that controls CsFAD3 in camelina.…”

Accelerating gene function discovery by rapid phenotyping of fatty acid composition and oil content of single transgenic T1 Arabidopsis and camelina seeds

“…Our T 1 results show that the frequency of co-suppression is the same as that identified in higher generation (Figures 5a and 2b of Du et al, 2018); (f) This strategy can also be useful to exclude some indirect effects. For instance, oil content is affected by maternal pod photosynthesis efficiency (Wei et al, 2011), and histone acetylation is involved in fatty acid biosynthesis in Arabidopsis seeds (Wang et al, 2016). Many maternal effects can be obviously avoided with this strategy, because both T 1 seeds and non-transgenic control seeds are from the same maternal plants.…”

Genome Wide Analysis of Fatty Acid Desaturation and Its Response to Temperature

“…Zhu et al (2012) reported that FAD2 expression is enhanced by low temperatures in the developing seeds of oilseed rape. Interestingly, Wang et al (2016) recently reported that Arabidopsis mutants in a number of histone deacetylases exhibit changes in seed fatty acid composition and that H3K9/14 acetylation of FAD3 influences its expression level (Wang et al, 2016). DNA acetylation in Arabidopsis has been implicated in heat stress-responsive gene expression (Hu et al, 2015).…”