Reelin signaling during dendritic initiation

Reelin is secreted by Cajal-Retzius neurons and activates a signaling pathway that orchestrates cellular positioning and dendritogenesis in the developing cortex. We have found that the that reelin triggers rapid orientation and dendritogenesis of layer 6 neurons (Nichols & Olson 2010; O’Dell et al., 2012). Direct visualization of the reelin response deep layer neurons revealed a fundamental defect in oriented dendritic growth in the reeler mutant. Absent reelin, neurons are tangentially oriented and unstable. Addition of reelin protein causes the tangential neurites to retract and the elaboration of a radially-directed apical dendrite (checkout the movie page). Collaboration with Dr. Warren Zipfel, Department of Bioengineering, Cornell University. Support NINDS R01NS066071

Paxillin and Hic5 focal adhesion adaptors in cortical development

Paxillin family members, Paxillin, Hic5 and Leupaxin are focal adhesion adaptors that work closely with Src and Fak kinases and link the cell to the extracellular matrix. We find that Paxillin and Hic5 are highly expressed during preplate splitting. Mamunur Rashid in the laboratory has found that deficiency in Paxillin delays cortical migration and disrupts normal migrating neuron morphology. Collaboration with Dr. Christopher Turner, Department of Cell and Developmental Biology, SUNY Upstate Medical University.Support NINDS R01NS066071

Ethanol disruption of dendritic initiation and growth

The Developmental Exposure to Alcohol Research Center (DEARC) is a multi-institutional center directed by Drs. Linda Spear, Terry Deak and David Jentsch at SUNY Binghamton University. As part of the DEARC, our lab is exploring the consequence of early ethanol exposure on neurite dynamics in the developing cortex. We have found that ethanol interferes with the dendritic filopodial targeting and dendritic organization. This work suggests that dendritic filopodia are extraordinarily sensitive to their local environment (and to toxic insult). Support NIAAA P50AA015850-01 RC#1.

  • We are supported by P50AA017823, an NIH funded center for the study of developmental exposure to alcohol.

  • We are grateful for additional support from a Clark Pediatric Research Award and prior support from a grant NINDS R01NS066071