Meeting Abstract
The lateral line (LL) is a hair cell-based sensory system that is important for swimming coordination, schooling, rheotaxis, and predator/prey detection in aquatic vertebrates. Previous behavioral studies have often relied on acute disruption of LL function by ototoxic compounds, but a genetic model is preferable to better understand the long-term contribution of the LL to fish behavior and learning. However, since inner ear and LL hair cells share many core functional components, it has been challenging to find a genetic mutant which specifically disrupts LL function. This work describes the first genetic model for the congenital loss of LL function in adult fish. We have found zebrafish ohnologs of a gene required for hair cell function whose mRNA expression patterns are cleanly partitioned between inner ear and LL hair cell populations. Genetic disruption of each ohnolog results in specific loss of either auditory/vestibular function or LL function. Since the LL mutants are adult-viable and exhibit normal auditory and vestibular behaviors, we can investigate LL-mediated behaviors and learning in adult fish. We have begun our analysis of these “lateral line-less” fish by evaluating their growth, survivability, and rheotactic behavior. We also characterize a novel swim bladder over-inflation phenotype associated with the LL mutants. In summary, this novel genetic mutant provides a unique opportunity to study lateral line function and to examine the long-term contributions of the lateral line input to fish development and behavior.
