SPATULA and ALCATRAZ confer fruit cavity and female sterility via mediating transmitting tract development in cucumber

The successful fusion of sperms and eggs need firstly the reception of pollens by stigmatic papillae, and then the unobstructed transmitting tract (TT) providing an extension channel for pollen tubes carrying with sperm cells. However, the genes involved in transmitting tract specification and cavity formation in cucumber remained largely unknown. Here, we characterized the bHLH gene, Cucumis sativus SPATULA (CsSPT) and its redundant function with Cucumis sativus ALCATRAZ (CsALC) in TT development and stigma convergence in cucumber. Overall design: Stigmas of wild type and Csspt, Csalc, Csspt Csalc mutants at athesis were collected for RNA-seq analysis. Three biological replicates were performed.