Hanse Lectures in Neurosciences: “The role of tryptophan-rich basic protein (Wrb) in sensory hair cell exocytosis and hearing”

Dr. Tina Pangrsic Vilfan is Junior Research Group Leader of the Group "Synaptic physiology of mammalian vestibular hair cells", Institute for Auditory Neuroscience & Innerearlab at the University Medical Center Göttingen and a specialist in synaptic physiology of the auditory system.

She speaks about:
“The role of tryptophan-rich basic protein (Wrb) in sensory hair cell exocytosis and hearing”.
Abstract:
The transmembrane recognition complex (TRC40) pathway mediates the insertion of tail-anchored (TA) proteins into membranes of nucleus, endoplasmatic reticulum (ER), mitochondria and plasma membrane. Tryptophan-rich basic protein (WRB) was recently identified to act as a TRC40-receptor on the ER membrane. One of the TA is otoferlin, which is required for calcium-regulated neurotransmitter release at the inner hair cell (IHC) ribbon synapse. In the talk I will present a collaborative study investigating the impact of defective TA protein insertion on hearing. A selective deletion of the Wrb from hair cells led to progressive hearing impairment, which could not be ascribed to defective mechanotransduction, hair cell depolarization or presynaptic Ca2+ channels.  Wrb-deficient IHCs showed reduced otoferlin levels and fewer ribbon-associated vesicles. They displayed normal fast exocytosis but impaired synaptic vesicle replenishment as detected by in vitro patch-clamp membrane capacitance measurements. Auditory fatigue was further observed by in vivo recordings from postsynaptic spiral ganglion neurons. We conclude that the deletion of the Wrb gene perturbs the membrane insertion of otoferlin, thereby affecting IHC presynaptic function and sound encoding.

Lecture and discussion from 7:00 pm until approximately 8:00 pm followed by dinner and informal discussion in the HWK Bistro.

The lecture is open to everybody, but registration is required for this event (by replying to mdaniel@h-w-k.de).