PpyABF3 recruits the COMPASS‐like complex to regulate bud dormancy maintenance via integrating ABA signaling and GA catabolism

Abstract

Bud dormancy is essential for perennial trees that survive the cold winters and to flower on time in the following spring. Histone modifications have been reported to be involved in the control of the dormancy cycle and DAM/SVPs are considered targets. However, how the histone modification marks are added to the specific gene loci during bud dormancy cycle is still unknown.Using yeast-two hybrid library screening and co-immunoprecipitation assays, we found that PpyABF3, a key protein regulating bud dormancy, recruits Complex of Proteins Associated with Set1-like complex via interacting with PpyWDR5a, which increases the H3K4me3 deposition at DAM4 locus.Chromatin immunoprecipitation-quantitative polymerase chain reaction showed that Ppy-GA2OX1 was downstream gene of PpyABF3 and it was also activated by H3K4me3 deposition. Silencing of GA2OX1 in pear calli and pear buds resulted in a similar phenotype with silencing of ABF3. Furthermore, overexpression of PpyWDR5a increased H3K4me3 levels at DAM4 and GA2OX1 loci and inhibited the growth of pear calli, whereas silencing of PpyW-DR5a in pear buds resulted in a higher bud-break percentage.Our findings provide new insights into how H3K4me3 marks are added to dormancyrelated genes in perennial woody plants and reveal a novel mechanism by which ABF3 integrates abscisic acid signaling and gibberellic acid catabolism during bud dormancy maintenance.

Genetic and molecular regulation of chilling requirements in pear: breeding for climate change resilience

“…Functional studies of PpyWDR5a overexpression results in a higher level of histone modification in DAM4, leading to growth cessation of pear calli, whereas silencing PpyWDR5a (VIGS) increases budbreak percentage. These results suggest that PpyWDR5a regulates the expression of DAM4 (Guak and Fuchigami, 2001;Zheng et al, 2015;Wang et al, 2016;Yang et al, 2023).…”

Genomic basis of the distinct biosynthesis of β‐glucogallin, a biochemical marker for hydrolyzable tannin production, in three oak species

“…Phylogenetic and molecular evolutionary analyses were conducted using mafft (https://mafft.cbrc.jp/alignment/software/) and IQ‐TREE (Nguyen et al ., 2014). The maximum‐likelihood method was used with 1000 bootstrap values and the trees were visualized using i TOL (https://itol.embl.de/) (Letunic & Bork, 2021) as described in our previous study (Yang et al ., 2022). For the small phylogenetic tree of UGTs, the neighbor‐joining method was used in M ega 7 (Kumar et al ., 2016) with full‐length protein sequences.…”

Advancing tree genomics to future proof next generation orchard production

“…Transcriptomic studies in various other species including WT-717 poplar hybrid, Japanese pear and raspberry (Rubus idaeus) show that DAMs, as well as important genes involved in abscisic acid (ABA) and GA synthesis and catabolism differentially accumulate in buds transitioning from growth cessation through the different stages of dormancy to growth resumption in spring (Mazzitelli et al, 2007;Ruttink et al, 2007;Niu et al, 2016). ABA has been shown to control dormancy by inhibiting genes involved in cell proliferation and growth, and activating catabolism genes of other hormones such as GAs (Yang Q. et al, 2023). However, the exact signalling cascades by which DAMs trigger ABA and GA pathways in response to environment are still obscure.…”