Chemically-induced DNA de-methylation alters the effectiveness of microspore embryogenesis in triticale. (October 2019)

• Record Type: Journal Article
• Authors: Nowicka, Anna; Juzoń, Katarzyna; Krzewska, Monika; Dziurka, Michał; Dubas, Ewa; Kopeć, Przemysław; Zieliński, Kamil; Żur, Iwona
• Is Part Of: Plant science. Volume 287(2019)
• Publication Date: 2019-10
• Subjects: AC 5-azacytidine -- AR albino regenerated plants -- a.u. arbitrary units -- DAC 2′-deoxy-5-azacytidine -- DAPI 4′6-diamidino-2-phenylindole -- DHs doubled haploids -- DM dead microspores -- ELSs embryo-like structures -- EM embryogenic microspores -- FDA fluorescein diacetate -- GR green regenerated plants -- ME microspore embryogenesis -- mcs microspores -- N-EM non-embryogenic microspores -- R regenerated plants -- RdDM RNA-directed DNA methylation -- SEM standard error of the mean -- TUNEL TdT-mediated dUTP nick end labelling -- 5-mdC 5-methyl-2′deoxycytidine; DNA methylation -- 5-azacytidine -- 2′-deoxy-5-azacytidine -- Cytotoxicity -- Double haploid -- ×Triticosecale Wittm; Botany -- Periodicals; Botanique -- Périodiques; 580
• DOI: 10.1016/j.plantsci.2019.110189
• Languages: English
• ISSNs: 0168-9452

Abstract

Highlights: Responsive and recalcitrance lines of triticale differ with respect to phenotypic, genetic and epigenetic features. There is a link between the formation of DNA damage and cytidine-analogs induced DNA de-methylation. The application of 5-azacytidine increases the efficiency of microspore embryogenesis in the highly-responsive line. Abstract: Microspores exposed to some stress factors may display cell totipotency and could be reprogrammed towards embryogenic development. Plant breeding and genetic engineering widely use haploids/doubled haploids (DHs) derived from in vitro -cultured microspores, but the mechanism of this process remains poorly understood. Recently published data suggest that microspore embryogenesis (ME) is accompanied by changes in DNA methylation and chromatin reorganization. Here, we used two triticale DH lines (DH19 and DH28), significantly different with respect to embryogenic potential. To change DNA methylation levels, we applied two cytosine-analogs: 5-azacytidine (AC) and 2′-deoxy-5-azacytidine (DAC) treatments. We found that chemically-induced DNA demethylation caused chromatin relaxation and dysregulation of marker genes ( TaTPD1-like, GSTF2, GSTA2, CHI3, Tad1, TaNF-YA7, SERK2, TaME1 ) related to ME. Both drugs showed significant cytotoxicity in a dose-dependent manner. We noticed that lines varied in terms of overall DNA methylation levels and responded in a different way to hypomethylation caused by the drugs. DH19 (low embryogenic) after inhibitors treatment, showed higher microspore viability, but its recalcitrancy was not overcome. For highly embryogenic DH28, we noted significantly higher effectiveness of embryo-like structure production and plant regeneration. In summary, our study provides new insight into the role of DNA methylation in ME initiation. They suggest potential benefits resulting from the utilization of epigenetic inhibitors to improve the process of DHs production.