Cas9-IAA9 Binary Vector Construct

Background

Seed lessness is a desired trait in elite cultivars intended for the fastidious consumers who find the seeds to impair the processing quality of the fruits. Seed lessness can be of advantage for processed tomato products because the energy invested in separating the seeds from the processed product can be saved. Thus parthenocarpy can be beneficial to seed companies as it assists in protecting their varieties. Auxin/indole-3-acetic acid (Aux/IAA) proteins are transcriptional regulators involved in auxin-regulated plant development, and a loss-of-function IAA9 mutant tomato formed parthenocarpy fruit (Wang et al. 2005), suggesting that IAA9 is also a negative regulator of auxin involved in regulating parthenocarpy fruit set. IAA9 protein prevents ovary development prior to pollination by acting as a negative regulator of auxin response pathways. Downregulation of IAA9 causes the release of early auxin-responsive genes, thus mimicking the burst of auxin produced in the ovary during pollination leading to parthenocarpy. The present innovation named "CRISPR/Cas9-IAA9 binary vector construct" was created to generate parthenocarpy tomato fruits.