Characterization of EcROS1-like, a putative gene indirectly involved in apomixis in Eragrostis curvula

JOSÉ CARBALLO; JIMENA GALLARDO; CRISTIAN ALEJANDRO CHEMIN GENOVA; JUAN PABLO SELVA; VIVIANA ECHENIQUE; DAMIR SIMÓN; DIEGO ZAPPACOSTA

Santa Fe

Congreso; XXXIII Argentinian meeting of Plant Physiology (RAFV2021); 2021

Eragrostis curvula is a forage grass native from southern Africa that has become a model species to understand apomictic mechanisms, especially diplosporous development. E. curvula presents mainly facultative genotypes that retain percentage of sexual pistils that increase under drought and other stressful situations, indicating that some regulators activated by stress could be affecting the apomixis/sexual switch. Water stress experiments were performed in order to associate the increase of sexual embryo sacs with the differential expression of genes in a facultative apomictic cultivar Don Walter (DW) using cytoembryology and RNA sequencing. Interestingly Repressor of Silencing 1 (ROS1) the gene involved in the demethylation, was found overexpressed in stressed plants, hence, demethylating certain genes and allowing the increase of sexuality in the facultative genotype DW The objective of this work was to assess the genomic structure of the gen and find out the differences between cultivars with different reproductive modes (Facultative DW, obligate apomictic Tanganyica USDA, and sexual genotypes Victoria and OTA-s USDA. Genomic and transcriptoma sequences information from previously reported works was used to model and compare the genomic structure of the gen and validated by cloning and sequence partial regions of the gene in the different cultivars. The genomic structure shows that EcROS1 is composed by a total of XXX bp, XX exons and XX introns, and five different isoforms were found in facultative cultivar DW and four isoforms in the obligate and sexual genotypes, these results will be useful for expression studies to differentiate the expression of different isoforms.