HD2-type histone deacetylases: unique regulators of plant development and stress responses

Abstract

Plants have developed sophisticated and complex epigenetic regulation-based mechanisms to maintain stable growth and development under diverse environmental conditions. Histone deacetylases (HDACs) are important epigenetic regulators in eukaryotes that are involved in the deacetylation of lysine residues of histone H3 and H4 proteins. Plants have developed a unique HDAC family, HD2, in addition to the RPD3 and Sir2 families, which are also present in other eukaryotes. HD2s are well conserved plantspeci c HDACs, which were rst identi ed as nucleolar phosphoproteins in maize. The HD2 family plays important roles not only in fundamental developmental processes, including seed germination, root and leaf development, oral transition, and seed development, but also in regulating plant responses to biotic and abiotic stresses. Some of the HD2 members coordinate each other to function. The HD2 family proteins also show functional association with RPD3-type HDACs and other transcription factors as a part of repression complexes in gene regulatory networks involved in environmental stress responses. This review aims to analyse and summarise recent research progress in the HD2 family, and to describe their role in plant growth and development and in response to different environmental stresses.

Genome-Wide Analysis of the HDAC Gene Family and Its Functional Characterization at Low Temperatures in Tartary Buckwheat (Fagopyrum tataricum)

“…Additionally, flavonoids such as quercetin were found to fight against COVID-19 [ 3 ]. In recent years, the research of Tartary buckwheat has become increasingly popular, and the genome is constantly being sequenced and annotated [ 4 , 5 , 6 , 7 , 8 , 9 ]. More studies are being conducted on Tartary buckwheat, especially on the synthesis of bioactive flavonoids.…”

“…Histone deacetylases (HDACs) are important epigenetic regulators in eukaryotes and are involved in the deacetylation of histone lysine and arginine residues of the H3 and H4 histone. Furthermore, HDACs are highly conserved in many organisms [ 4 , 5 ]. In plants, histone deacetylation is carried out by three HDAC families: RPD3/HDA1, SIR2, and the plant-specific HD2 family [ 6 ].…”

HDACs Gene Family Analysis of Eight Rosaceae Genomes Reveals the Genomic Marker of Cold Stress in Prunus mume

“…The Arabidopsis HOS15, a WD40-repeat protein, interacts with HDACs to regulate the plant development process [ 56 , 57 ], particularly, functions as a repressor to control cold stress-regulated gene expression through chromatin modification [ 58 , 59 ]. HD2 proteins also play important roles in abiotic stress responses, including cold [ 41 , 59 , 60 , 61 ]. AtHD2C (AtHDT3) interacts with HOS15, associated with cold signaling gene COR (COLD RESPONSIVE) and CBF (C-REPEAT (CRT) BINDING FACTOR) in response to cold stress [ 58 ].…”

HD2A and HD2C co-regulate drought stress response by modulating stomatal closure and root growth in Arabidopsis

“…The N-terminal lysine residues of histone H3 and H4 allow for different post-translational histone modifications, inculding acetylation, phosphorylation, methylation, sumoylation and ubiquitination ( Kapazoglou and Tsaftaris, 2011 ; Zhou et al., 2013 ). These modifications of lysine residues act as a switch to activate or repress the expression of associated genes, and therefore offer a flexible mode of gene expression regulation in developmental programming and abiotic stress response ( Kurdistani et al., 2004 ; Kouzarides, 2007 ; Tahir and Tian, 2021 ). Histone acetylation and deacetylation are dynamic reversible processes and are catalysed by histone acetyltransferases (HATs) and histone deacetylases (HDACs), respectively.…”

“…The HD2 family HDACs share no sequence homology to yeast HDACs and are found only in plants and green algae ( Ma et al., 2013 ; Bourque et al., 2016 ). The HD2 family, being unique to plants, is emerging as an important regulator in different aspects of plant development and plant response to different biotic and abiotic stresses ( Tahir and Tian, 2021 ).…”