Comparative analysis of LTR retrotransposons populations inhabiting potato, tomato and pepper genomes.

ROSALÍA C. PAZ ; ANAHÍ YAÑEZ; NATALIA P. ANDINO; PAULA B. PAZ; M. VIRGINIA SANCHEZ-PUERTA

Fos Iguazu

Congreso; 11 The International Congress of Plant Molecular Biology; 2015

Comité Organizador IPMB2015: Silvina Pessino (UNR), Fernando Carrari (IB-INTA, CONICET, FAUBA), Viviana Etchenique, (UNS, representante de RedBio), Pablo Cerdán, Marcelo Yanovsky, Santiago Mora García (Fundación Instituto Leloir, FIL), Sebastián Asurmendi

Potato (Solanum tuberosum, genome size ~0.84Gb), tomato (Solanum lycopersicum, ~0.95Gb) and pepper (Capsicum annum, ~3.20 Gb) are species of high economic value for its agronomical importance. Those species belong to Solanacea family, being the divergence between pepper and tomato-potato ancestor and between tomato and potato ancestor estimated in 19.6 mya and 7.3 mya respectively. Recently, the genome of those species (in the case of potato, the related double monoploid S. Phureja) were sequenced reveling there are considerable colinearity among them, being differences in genome size attributed to the accumulation of LTR retroelements. Several estimations of retroelement density were conducted within the genome of those species; however, those studies focuses mainly on the analysis of LTR portion. We performed a genome-wide LTR retroelement annotation based on structural and functional selection for the identification of potentially active retroelements. We identified numerical differences and Copia:Gypsy (C:G) ratios between the genomes, containing potato, tomato and pepper 229 (C:G=3.5), 737 (C:G=0.8) and 1339 (C:G=2.3) retroelements respectively. We also identified differences in phylogenetic clade radiation within each species, being the expansion attributed to Retrofit, Del and Athila clades for potato, tomato and pepper respectively. Some phylogenetic clades are absent in species, such as CRM in tomato and Tat in potato. Despite some families of known LTR retroelements are common for all the analyzed species (such as Tnt1, Tto1, Torl1), there are families exclusives within each specie. The application of this information for molecular marker design will be discussed. Funding: D-TEC 0008/13 (AGENCIA, MINCyT, Argentina).