SpMS1, a male sterility factor, interacts with SpAP1 to regulate unisexual flower development in dioecious spinach.

This article focuses on the identification and functional characterization of the spinach MALE STERILITY1 gene (SpMS1) as a key regulator of male fertility and unisexual flower development in dioecious spinach (Spinacia oleracea). SpMS1, an ortholog of Arabidopsis MS1, is expressed predominantly in the tapetum during specific pollen developmental stages and acts as a masculine factor; silencing SpMS1 causes male sterility and induces masculinization in female flowers, while its overexpression in Arabidopsis leads to male sterility and can partially rescue the Arabidopsis ms1 mutant phenotype. The study also demonstrates that SpMS1 interacts with the MADS-box transcription factor SpAP1, suggesting a protein complex that regulates sex differentiation and unisexual flower development in spinach. These findings provide insights into the molecular mechanisms of sex determination in dioecious plants and offer potential applications for manipulating male sterility in plant breeding.