The Caenorhabditis elegans heterochronic gene lin‐14 coordinates temporal progression and maturation in the egg‐laying system

Heterochronic genes function to ensure the timing of stage‐specific developmental events in C. elegans . Mutations in these genes cause certain developmental programs to be executed in a precocious or retarded manner. Canonical precocious (loss‐of‐function) and retarded (gain‐of‐function) mutations in the lin ‐ 14 gene lead to elimination or reiteration of larval stage‐specific cellular events. Here, we describe a hypomorphic, missense allele of lin ‐ 14 , sa485 . lin‐14(sa485 ) hermaphrodites pass through normal larval stages, but exhibit asynchrony between vulval and gonadal maturation in the L4 larval stage. We show that a subtly precocious morphogenetic event in the vulva disrupts tissue synchrony and is followed by retarded vulval eversion. Additionally, uterine uv1 cell differentiation is retarded in lin‐14(sa485 ) animals that exhibit delayed vulval eversion. Together, these experiments outline a function for LIN‐14 in coordinating the temporal progression of development, which is separable from its role in regulating stage‐specific events during C. elegans postembryonic development. Developmental Dynamics 238:394–404, 2009. © 2009 Wiley‐Liss, Inc.