Genetic and molecular bases of cucumber (Cucumis sativus L.) sex determination

Abstract

Despite the importance of plant sex determination in genetic diversity, there is no clear picture of the regulation of this process. Cucumber has recently emerged as an excellent model system to explore sex determination. In this review, we describe the current state of sex determination in cucumber and propose a model to explain the regulation of the molecular processes controlling this phenomenon. Transcriptional profiling of hormonally controlled genes involved in sex-specific patterns of floral development has progressed from genetic-based studies to direct RNA analysis and from gene-by-gene examinations to genomic-scale analyses. Floral development comprises an orchestrated series of processes that are ordered in accordance with plant genetic background. Moreover, they are regulated at multiple levels by endogenous and environmental factors. Recent findings have contributed to a better understanding of sex expression and will undoubtedly inspire new applications and research into mechanisms underlying the development, function, and evolution of cucumber sex determination and floral morphogenesis. Intensive investigation of potential sex determination genes in model species is anticipated to aid the elucidation of the sex determination gene network and should have a significant impact on plant breeding.