GG13: a candidate gene related to seed development and viability from apomictic Paspalum notatum

Abstract

One way to transfer apomixis (asexual reproduction through seeds) to major crops could be through genetic transformation, but for this a set of transgenes that triggers each of the involved processes should be generated. Although most angiosperms require an endospermic balance number (EBN) for normal endosperm development, tetraploid Paspalum notatum is EBN- insensitive. Here, a candidate gene (GG13) of Paspalum notatum associated with endosperm development in insensitive EBN crosses was analyzed by gene silencing in Arabidopsis thaliana. When comparing the silenced and control conditions, silenced condition evidenced less relative expression in RT-qPCR experiments, more abortions (6 vs. 1), fewer seeds (16 vs. 34), a more elongated shape (shape index 1.83 vs. 1.57), and lower germination (4 vs. 36 %) in phenotypic analyses. The above results were consistent with bioinformatically predicted functions for GG13 gene. Therefore, the importance of the GG13 gene in endosperm development in EBN-insensitive seeds was demonstrated, offering the possibility of incorporating apomixis into major crops.