Molecular Analyses of Gonad Differentiation and Function in Zebrafish

Abstract

Zebrafish is an important vertebrate model organism that has helped researchers to unveil many interesting biological questions, especially those related to early embryogenesis. However, our current knowledge on zebrafish gonad differentiation and function is limited. Juvenile hermaphroditism is the mode of gonad differentiation where both mature ovary and testis are developed from the bipotential `juvenile ovary¿. Oocyte apoptosis is thought to be involved in the gonadal transformation process. To investigate the role of apoptosis during testis development, we chemically suppressed apoptosis using a broad spectrum anti-apoptotic drug. In our study, when apoptosis was blocked during gonadal transformation, testis development was remarkably delayed. After one week of treatment, prospective individuals destined to be males underwent gonadal transformation, suggesting the necessity of oocyte apoptosis during testis formation in zebrafish. Moreover, expression profiling using Gonad Uniclo