Seminars and Events

Past Events

Category Seminar
Date and Time 2009-04-24 16:00 - 17:00
Venue Seminar Room A7F
Speaker Miho Matsuda
Affiliation Section on Neural Developmental Dynamics, LMG, NICHD, NIH, USA
Title Notch signaling is essential for coordinating cell fate, morphogenesis and migration in the lateral line primordium
Poster click here to download(PDF)
Host Shigenobu Yonemura
abstract The lateral line is a sensory system designed to sense directional water movement. It is a model for understanding sensory hair cell development in vertebrates. The lateral line consists of hundreds of small cellular units, called neuromasts. In the zebrafish, the posterior lateral line primordium (pLLp) migrates caudally and periodically deposits neuromasts. Each neuromast, formed within the migrating pLLp, has a center-oriented epithelial rosette and a central atoh1-positive hair cell determined by Notch mediated-lateral inhibition. Previous studies suggest that morphogenesis, deposition of neuromasts and pLLp migration are coordinated by two mutually antagonistic signaling centers, a Wnt signaling center at the leading edge and a FGF signaling center in the adjacent domain. However, it is not fully understood how these signaling centers are maintained during the pLLp migration and neuromast depositions. In this study, we hypothesized that the single atoh1-positive cell at the center of each neuromast also might contribute to its coordinated morphogenesis. Live imaging of the pLLp in mib mutants, which have lost function of an E3 ubiquitin ligase essential for efficient Notch signaling, showed that mib pLLp deposited neuromasts irregularly, eventually stalled and dissociated into several small cell clusters. We analyzed FGF and Wnt activity in mib mutants. Our results suggest that Notch signaling-mediated lateral inhibition restricts FGF sources and helps maintain balanced FGF and Wnt signaling in the migrating pLL primordium.