The impact of cold and Trichostatin A treatment on the transcriptome of wheat microspores

Abstract

Obtaining doubled haploids plants from isolated microspores is valuable for plant breeders. Microspores generally require stress treatment to enter androgenesis and produce doubled haploids. RNA-seq analysis was performed on cultured microspores that have been subjected to a three-week cold treatment and exposure to the histone deacetylase inhibitor Trichostatin A. Results point to dramatic transcriptional reprogramming after cold pre-treatment; upregulation in transcription, cytoplasmic turn over, signal transduction through kinase cascades, and chromatin remodelling supporting a change in cell fate. Cold-stressed microspores are then able to respond to TSA treatment with transient genome-wide upregulation of several thousand genes, not seen in unstressed microspores. Pathways upregulated include mitotic cell cycle phase transition genes, transcription, and DNA recombination and repair. These pathways may explain the increase in androgenesis seen after application of TSA. Results shed light on the behavior of wheat microspores in culture and pave the way for improved androgenesis and DH production.