The grapevine AINTEGUMENTA gene VvANT1 is associated with variation in berry and ovary size

ESTEFANIA EICHLER; CONSTANZA CHIALVA; CECILIA GRISSI; CLAUDIO MUÑOZ; SEBASTIAN GOMEZ TALQUENCA; DIEGO LIJAVETZKY

Foz do Iguazú

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

Fruit size is a highly important trait for most fruit and vegetable crops. Several regions within the grapevine genome have been identified influencing berry size, mainly those related to seedlessness, but also particular transcription factors affecting cell number and/or cell size of flowers or berries. In this sense, the control of the intrinsic organ size has been thoroughly studied in Arabidopsis after the analysis of the function of the AINTEGUMENTA (ANT) TF. ANT, together with the AINTEGUMENTA-LIKE proteins (AIL proteins) are members of the APETALA 2/ETHYLENE RESPONSE FACTOR (AP2/ERF) domain family of TFs and are required for integument initiation and promotion of growth within developing floral organs.In this study, we evaluate the gene expression of the grapevine ANT and the AINTEGUMENTA-LIKE family during flower development and Berry ripening from cultivar Muscat Hamburg, as well as the expression of ANT on 11 different cultivars on developmental stage ?G?. We also analyzed the relationship between the cell number of ovaries from different grapevine cultivars and final size of the flowers and berries of those cultivars.The results showed the existence of a clear association between the berry and ovary size, and that the ovary cell number is a main determinant of ovary size. We also identified VvANT1 as a putative TF associated with the determination of the final berry size through affecting cell division during the flower development. VvANT1 mRNAs accumulates predominantly in the inflorescences, while its expression patterns strongly correlates with number of cells per ovary, the ovary size and the final berry size.