Distinctive Gene Expression Patterns Define Endodormancy to Ecodormancy Transition in Apricot and Peach

Jiali Yu; Anna O Conrad; Véronique Decroocq; Tetyana Zhebentyayeva; Daniel E Williams; Dennis Bennett; Guillaume Roch; Jean-Marc Audergon; Christopher Dardick; Zongrang Liu; Albert G Abbott; Margaret E Staton

doi:10.3389/fpls.2020.00180

Distinctive Gene Expression Patterns Define Endodormancy to Ecodormancy Transition in Apricot and Peach

Front Plant Sci. 2020 Feb 28:11:180. doi: 10.3389/fpls.2020.00180. eCollection 2020.

Authors

Affiliations

¹ Genome Science and Technology Program, University of Tennessee, Knoxville, TN, United States.
² Forest Health Research and Education Center, University of Kentucky, Lexington, KY, United States.
³ Department of Plant Pathology, The Ohio State University, Columbus, OH, United States.
⁴ UMR 1332 Biologie du Fruit et Pathologie, Equipe de Virologie, INRA, Universite de Bordeaux, Villenave d'Ornon, France.
⁵ Department of Ecosystem Science and Management, Schatz Center for Tree Molecular Genetics, the Pennsylvania State University, University Park, PA, United States.
⁶ Center for Environmental Biotechnology, University of Tennessee, Knoxville, TN, United States.
⁷ Appalachian Fruit Research Station, United States Department of Agriculture-Agriculture Research Service, Kearneysville, WV, United States.
⁸ GAFL Fruit and Vegetable Genetics and Breeding, INRA Centre PACA, Montfavet, France.
⁹ Department of Entomology and Plant Pathology, Institute of Agriculture, University of Tennessee, Knoxville, TN, United States.

Abstract

Dormancy is a physiological state that plants enter for winter hardiness. Environmental-induced dormancy onset and release in temperate perennials coordinate growth cessation and resumption, but how the entire process, especially chilling-dependent dormancy release and flowering, is regulated remains largely unclear. We utilized the transcriptome profiles of floral buds from fall to spring in apricot (Prunus armeniaca) genotypes with contrasting bloom dates and peach (Prunus persica) genotypes with contrasting chilling requirements (CR) to explore the genetic regulation of bud dormancy. We identified distinct gene expression programming patterns in endodormancy and ecodormancy that reproducibly occur between different genotypes and species. During the transition from endo- to eco-dormancy, 1,367 and 2,102 genes changed in expression in apricot and peach, respectively. Over 600 differentially expressed genes were shared in peach and apricot, including three DORMANCY ASSOCIATED MADS-box (DAM) genes (DAM4, DAM5, and DAM6). Of the shared genes, 99 are located within peach CR quantitative trait loci, suggesting these genes as candidates for dormancy regulation. Co-expression and functional analyses revealed that distinctive metabolic processes distinguish dormancy stages, with genes expressed during endodormancy involved in chromatin remodeling and reproduction, while the genes induced at ecodormancy were mainly related to pollen development and cell wall biosynthesis. Gene expression analyses between two Prunus species highlighted the conserved transcriptional control of physiological activities in endodormancy and ecodormancy and revealed genes that may be involved in the transition between the two stages.

Keywords: Prunus; RNASeq; bloom date; chill requirement; co-expression network; dormancy; floral buds; transcriptome.