Expression analysis of auxin induced protein (Aux/IAA) and it possible association with apomixis control in Paspalum notatum.

AZZARO CELESTE ANTONELA; ORTIZ JAUN PABLO AMELIO; SIENA LORENA ADELINA; PESSINO SILVINA CLAUIDIA; STEIN JULIANA

Foz de Iguazú

Congreso; XXII International Congress of Genetics; 2018

Apomixis is a natural asexual mode of reproduction by seeds. The introgression of the character into sexual crops would greatly expand the current breeding and seed production capacity. In Paspalum notatum, apomixis segregates as a simple dominant locus (Apospory Controlling Locus) with a distorted segregation ratio. Comparative mapping analyses revealed that a segment of rice chromosome 12 is syntenic to the Paspalum ACL in at least four species of the genus. This chromosome segment, of about 5.8 cM, likely includes key apomixis governing genes. One of the candidates mapping at this area is LOC_Os12g40890 (Os12g0601300), which encodes an induce auxin protein (Aux/IAA). The objective of this work was to investigate the expression of genes orthologous to Os12g0601300 in the floral transcriptome of P. notatum and to determine the expression levels in the apomictic Q4117 and the sexual Q4188 accessions. Using Os12g0601300 cDNA sequence as query in BLASTx and BLASTn searches on a Roche 454 floral transcriptome database of P. notatum were detected five sequences. One of them (isotig33023) shows differential representation (p < 0.01 y logFC > 3) among accesions. The in vivo expression levels was evaluated by qRT-PCR experiments on a cDNA from four development floral stages (pre-meiosis, meiosis, post-meiosis and anthesis). The qRT-PCR amplifications showed significant differences expression between Q4117 and Q4188 at meiosis stage. Ours results indicate that at least five genes that encode Aux/IAA proteins are expressed during the floral development of P. notatum. One of them shows expression differences at meiosis stage possibly associated with the mode of reproduction.