Temporal and spatial expression of the auxin induced protein IAA30 and its possible association with apomixis in Paspalum notatum.

SIENA LORENA ADELINA; ORTIZ JAUN PABLO AMELIO; PODIO, MARICEL; AZZARO CELESTE ANTONELA; PESSINO SILVINA CLAUIDIA

Mendoza

Congreso; XVII Congreso Latinoamericano de Genética; 2019

Apomixis is an asexual mode of reproduction by seeds. The introgression of this trait into sexual crops would greatly contribute to expand the use of heterosis and increase food production. In Paspalum spp., apomixis behaves as a simple-dominant locus with distorted segregation, which is syntenic to a segment of rice chromosome 12. This segment (5.8 cM) likely includes key genes for apomixis control and expression. One of these positional candidates, Os12g0601300, encodes for the auxin induced protein IAA30. The objective of this work was to investigate the presence of Os12g0601300 orthologs in the floral transcriptome of P. notatum, and analyze their expression levels in apomictic (Q4117) and sexual (Q4188) accessions. BLASTx and BLASTn searches on a floral transcriptome database of P. notatum detected five putative orthologous sequences. One of them (isotig33023) showed differential representation (p < 0.01 y logFC > 3) between Q4117 and Q4188. qRT-PCR assays were carried out at four floral development stages (pre-meiosis, meiosis, post-meiosis and anthesis) using two reference genes (β-tubulin and G6PDH). Isotig33023 resulted significantly upregulated in Q4117 compare to Q4188 at meiosis, post meiosis and anthesis stages. Our results indicate that at least five genes expressed in the floral transcriptome are putative IAA30 orthologs. One of them showed higher expression in the apomictic genotype (Q4117) from meiosis to anthesis, which could indicate an association with the apomictic mode of reproduction. Further qRT-PCR analyses are being conducted on several apomictic and sexual individuals to confirm a correlation between differential expression and the reproductive mode.