Histone Deacetylase Inhibitor SAHA Improves High Salinity Tolerance Associated with Hyperacetylation-Enhancing Expression of Ion Homeostasis-Related Genes in Cotton

Abstract

Histone acetylation plays an important role in regulation of chromatin structure and gene expression in terms of responding to abiotic stresses. Histone acetylation is modulated by histone deacetylases (HDACs) and histone acetyltransferases. Recently, the effectiveness of HDAC inhibitors (HDACis) for conferring plant salt tolerance has been reported. However, the role of HDACis in cotton has not been elucidated. In the present study, we assessed the effects of the HDACi suberoylanilide hydroxamic acid (SAHA) during high salinity stress in cotton. We demonstrated that 10 μM SAHA pretreatment could rescue of cotton from 250 mM NaCl stress, accompanied with reduced Na+ accumulation and a strong expression of the ion homeostasis-related genes. Western blotting and immunostaining results revealed that SAHA pretreatment could induce global hyperacetylation of histone H3 at lysine 9 (H3K9) and histone H4 at lysine 5 (H4K5) under 250 mM NaCl stress, indicating that SAHA could act as the HDACi in cotton. Chromatin immunoprecipitation and chromatin accessibility coupled with real time quantitative PCR analyses showed that the upregulation of the ion homeostasis-related genes was associated with the elevated acetylation levels of H3K9 and H4K5 and increased chromatin accessibility on the promoter regions of these genes. Our results could provide a theoretical basis for analyzing the mechanism of HDACi application on salt tolerance in plants.

A histone deacetylase inhibitor enhances rice immunity by derepressing the expression of defense-related genes

“…Several studies have shown that treatment of NaBT, TSA, SAHA can increase the acetylation level of histone H3 and H4 ( Chua et al., 2003 ; Ueda et al., 2017 ; He et al., 2020 ), and treatment of LBH-589 can increase the acetylation level of histone H3 ( Ueda et al., 2017 ). In order to investigate the effect of these four HDACis on the level of histone acetylation in rice, we treated rice seedlings with 10 mM NaBT, 1 mM SAHA, 1 mM LBH-589, and 1 mM TSA using the same method as described above.…”

“…For example, TSA treatment increases H4ac, H3K9ac, and H4K5ac levels in maize ( Hu et al., 2011 ), H3ac and H4ac levels in tobacco ( Chua et al., 2003 ), H3ac, H4ac, H3K14ac, H3K9ac, and H4K5ac levels in Arabidopsis ( Mengel et al., 2017 ). SAHA treatment increases H3ac and H4ac levels in cassava ( Patanun et al., 2016 ), H3K9ac and H4K5ac levels in cotton ( He et al., 2020 ). LBH-589 and NaBT treatment increases H3ac levels in Arabidopsis ( Ueda et al., 2017 ).…”

“…HDAC inhibitors (HDACis) can specifically inhibit the activity of HDAC, and are widely used to clarify the function of these enzymes. A variety of HDACis with different selectivity to HDAC proteins have been developed ( Waterborg, 2011 ; Patanun et al., 2016 ; Ueda et al., 2017 ; He et al., 2020 ). The research on application of HDACis in plants are also increasing.…”

Histone modifications and chromatin remodelling in plants in response to salt stress

“…In line with the A. thaliana study, another HDAC inhibitor, suberoylanilide hydroxamic acid (SAHA), enhanced the H3ac (acetylated H3) and H4ac levels in the roots of cassava and led to the upregulation of MeSOS1 expression, whereby conferring salt tolerance (Patanun et al, 2016). The SAHA application to cotton also led to a similar phenotype and consistent changes in the expressions of genes related to ion homeostasis, including those along the SOS pathway (He et al, 2020). Together with the findings from the mutants with altered H2Bub1 levels, these studies revealed that histone ubiquitination and acetylation might target different components in the SOS pathway to coordinate the regulation of salt tolerance in plants.…”

“…Such changes have been reported in several plant species. According to previous reports, salt stress led to an increase in the global level of at least one type of histone acetylation marks in A. thaliana, cassava, cotton, maise, rice and tobacco (He et al, 2020;Patanun et al, 2016;Sokol et al, 2007;Zhao, Wang, et al, 2014;. As histone acetylation is considered to be an activation mark, it was believed that its increase was important for facilitating the transcriptional responses to salt stress.…”