biostudies-literatureUnknownBrouilly NNEI NIH HHSNIDCD NIH HHSThe mammalian vestibular system has two types of sensory receptor hair cells (HCs), each with different neurotransmission mechanisms. Type II HCs use ribbon synapses to transmit neurotransmitters like glutamate to afferent neurons. On the other hand, type I HCs are nearly engulfed by a calyceal afferent ending and also form ribbon synapses. These HCs regulate afferent activity through non-quantal transmission (NQT), which is faster than classic neurotransmitter release and may play a key role in stabilizing vision and balance during rapid head movements. Here, we describe a novel striated contact, present between the mouse type I HC and its calyceal afferent ending, and intimately associated with atypical plasma membrane-apposed (PMA) mitochondria. This distinctive arrangement has the potebioRxiv : the preprint server for biology2025.03.21.644540https://www.ebi.ac.uk/biostudies/studies/S-EPMC11974672biostudies-literatureA novel membrane contact site in vestibular hair cells.PMC11974672R01 DC013771P30 EY001730Brouilly NPujol NEatock RACazevieille CPujol RStone JRichard FfalseA novel membrane contact site in vestibular hair cells.The mammalian vestibular system has two types of sensory receptor hair cells (HCs), each with different neurotransmission mechanisms. Type II HCs use ribbon synapses to transmit neurotransmitters like glutamate to afferent neurons. On the other hand, type I HCs are nearly engulfed by a calyceal afferent ending and also form ribbon synapses. These HCs regulate afferent activity through non-quantal transmission (NQT), which is faster than classic neurotransmitter release and may play a key role in stabilizing vision and balance during rapid head movements. Here, we describe a novel striated contact, present between the mouse type I HC and its calyceal afferent ending, and intimately associated with atypical plasma membrane-apposed (PMA) mitochondria. This distinctive arrangement has the pote2025-01-01T00:00:00Z2025 Mar2025-07-13T03:04:24.582Z2025-07-13T03:04:24.582ZS-EPMC119746724019665710.1101/2025.03.21.644540