Vulval development in C. elegans is dependent on the response of some of the central epidermal progenitor cells in the region of the developing vulva to a chemical signal from the gonad. Signaling from the gonad is blocked by action of the vulvaless mutant let-23 so that none of the central progenitor cells form vulval structures. In the vulvaless mutant, n300, the central progenitor cells do not form.

Which gene is likely to act earlier in the vulval developmental pathway?

Key Concepts

Vulval Development in C. elegans

Vulval development in C. elegans is a well-studied model of cell signaling and differentiation. It involves a series of interactions between the gonad and epidermal progenitor cells, which respond to specific signals to form vulval structures. Understanding this process is crucial for identifying the roles of various genes in development and how mutations can disrupt normal signaling pathways.

Gene Function and Mutations

Genes play specific roles in developmental pathways, and mutations can lead to altered functions or complete loss of function. In the context of the vulvaless mutant let-23, the mutation prevents the central progenitor cells from responding to gonadal signals, highlighting the importance of gene function in developmental processes. Identifying which gene acts earlier can provide insights into the hierarchy of signaling events.

Signaling Pathways

Signaling pathways are critical for cellular communication and development, involving ligands, receptors, and downstream effectors. In C. elegans vulval development, the signaling from the gonad is essential for the proper formation of vulval structures. Understanding the timing and interactions within these pathways helps in determining which genes are involved at various stages of development, particularly in mutants like n300.