Regulatory circuits involving bud dormancy factor PpeDAM6

Abstract

DORMANCY-ASSOCIATED MADS-BOX (DAM) genes have recently emerged as key potential regulators of the dormancy cycle and climate adaptation in perennial species. Particularly, PpeDAM6 has been proposed to act as a major repressor of bud dormancy release and bud break in peach (Prunus persica). PpeDAM6 expression is downregulated concomitantly with the perception of a given genotype-dependent accumulation of winter chilling time, and the coincident enrichment in H3K27me3 chromatin modification at a specific genomic region. We have identified three peach BASIC PENTACYSTEINE PROTEINs (PpeBPCs) interacting with two GA-repeat motifs present in this H3K27me3-enriched region. Moreover, PpeBPC1 represses PpeDAM6 promoter activity by transient expression experiments. On the other hand, the heterologous overexpression of PpeDAM6 in European plum (Prunus domestica) alters plant vegetative growth, resulting in dwarf plants tending toward shoot meristem collapse. These alterations in vegetative growth of transgenic lines associate with impaired hormone homeostasis due to the modulation of genes involved in jasmonic acid, cytokinin, abscisic acid, and gibberellin pathways, and the downregulation of shoot meristem factors, specifically in transgenic leaf and apical tissues. The expression of many of these genes is also modified in flower buds of peach concomitantly with PpeDAM6 downregulation, which suggests a role of hormone homeostasis mechanisms in PpeDAM6-dependent maintenance of floral bud dormancy and growth repression.

Evolutionary origin and functional specialization of Dormancy-Associated MADS box (DAM) proteins in perennial crops

“…6 ). Such transcriptional patterns truly support the growing hypothesis that DAM genes are not strictly associated with winter dormancy events, but instead are more general growth regulatory factors impinging on meristematic cell division and hormonal balances, with impact on the growth-stress survival trade-off, as suggested by recent studies [ 25 , 29 ].…”

“…Protein extraction, western blot and immunological detection was performed according to [ 29 ]. Briefly, Arabidopsis leaves were boiled in Laemmli buffer during 10 min at 95 °C.…”

“…A particular group of these SVP-like genes named DORMANCY-ASSOCI-ATED MADS-BOX (DAM) has been found deleted in the evergrowing (evg) mutant of peach (Prunus persica) showing no growth cessation during winter [13]. Since then, numerous molecular and functional approaches have provided plenty of evidences about the implication of DAM genes in regulating the dormancy cycle in Rosaceae species [14,15], namely in pear [16][17][18][19], apple [20][21][22], Japanese apricot [23][24][25], sweet cherry [26,27] and peach [28,29]. Also, DAM genes have been found transcriptionally associated with bud dormancy transitions in apricot [30], European plum [31], Chinese plum [32] and almond [33].…”

Male Meiosis as a Biomarker for Endo- to Ecodormancy Transition in Apricot

“…The limitations of the currently available methods, the increasing number of new releases in many fruit tree crops, as well as the decrease in winter chilling due to global warming have led to a number of recent research efforts focused on identifying suitable biomarkers to determine the transition from endo- to ecodormancy ( Martínez-Gómez et al, 2017 ; Lloret et al, 2018 ). These include starch accumulation within the ovary primordia cells ( Fadón et al, 2018a ) and hormone regulation ( Chmielewski et al, 2017 ; Vimont et al, 2019 ; Guillamón et al, 2020 ), as well as the expression of the DORMANCY-ASSOCIATED MAD-BOX (DAM) and other candidate genes in several Prunus species ( Bielenberg et al, 2004 ; Sánchez-Pérez et al, 2014 ; Rothkegel et al, 2017 ; Prudencio et al, 2018 , 2019 ; Balogh et al, 2019 ; Falavigna et al, 2019 ; Vimont et al, 2019 ; Quesada-Traver et al, 2020 ; Lloret et al, 2021 ). To deepen insights into the genetics of dormancy, transcriptomic studies have been performed by using flower buds at different dormant stages in apricot ( Yu et al, 2020 ; Canton et al, 2021 ), sweet cherry ( Vimont et al, 2019 ; Canton et al, 2021 ), almond ( Prudencio et al, 2020 ), or peach ( Yu et al, 2020 ; Canton et al, 2021 ).…”

Unravelling the Role of Epigenetic Modifications in Development and Reproduction of Angiosperms: A Critical Appraisal

“…Deletion in tandemly repeated sequences of MADS-box genes, i.e., DORMANCY-ASSOCIATED MADS-box gene (DAM1-6) leads to nondormant phenotype of evg mutant. DAM genes are expressed in buds and get affected by photoperiod and chilling temperatures, thereby affecting the developmental stages of plants ( Lloret et al, 2021 ). The concentration of DAM genes, i.e., DAM5 and DAM6, was found to be high in dormant buds, and after chilling treatment, the level fell and released the dormancy of buds ( Yamane et al, 2011 ).…”