Hindered tomato reproductive development by altered brassinosteroid sensitivity1 mutant

The extracellular domain of bri1 perceives brassinosteroids (BRs), and its signal transduction mediates the kinase signal transduction pathway. Disruption in this signaling kinase leads to significant alterations in regulatory pathways. However the regulatory mechanism of BR mediated reproductive development still remains elusive in plants. The expression pattern of BR-signaling components at different floral stages revealed that BR-signaling actively participates in various floral developmental stages, indicating its essential role in flower development. In this study, altered brassinosteroid sensitivity1 ( abs1 ) mutant was used to discover the regulatory roles of BR signaling in floral organ development. The abs1 mutant exhibited reduced expression of BR and Gibberellin (GA) related genes suggesting an essential role of BR and GA crosstalk during flower development. Furthermore, the abs1 mutant had a range of morphological abnormalities, notably altered flower structure and impaired male fertility. In addition, the tomato floral development and associated-pollen development were inhibited in the abs1 mutant. Our data reveals that curl3 might impact floral organs and pollen development via regulating BR and GA signaling in tomato. Overall, these findings provide a deeper understanding of morphological and transcriptional changes during flower development in response to BR-insensitivity. These insights may enhance efforts to improve fruit crop productivity through genetic engineering of curl3 via precise control of BR-signaling.