Abstract: In Momordica charantia L. the soluble protein profile of flower bud at hermaphroditic stage and three early developmental stages (the 7th, 10th and 13th day after initial budding) of male and female flowers were analysed with capillary electrophoresis. Some specific proteins related to sex differentiation were detected. The 11 kD protein, which appeared at the 7th day of budding and existed through the three developmental stages of the female flowers with little change of content, might be an "essential protein" for the expression of female flower differentiation program. Similarly, the 30 kD protein might be an "essential protein" for the expression of the male flower differentiation.

Key words: Momordica charantia, Specific protein, Sex differentiation