Perisynaptic Schwann cells of the vertebrate motor endplate bear modified cilia

Abstract

Perisynaptic Schwann cells (PSCs), descendants of the myelinating Schwann cells, cover the axon terminal of the vertebrate motor endplate of the skeletal muscle fiber. PSCs are assumed to support the function of the axon terminal. This function suggests a net material transport in the direction of the axon terminal. Morphologically it is to be expected that these cells have a cytoskeleton aligned to the axon terminal. Investigations clarifying this statement have not yet been undertaken. From previous investigations we know, however, that the PSCs have a microtubule-organizing center, which is a part of this cytoskeleton. The centrioles of the organizing center may also participate in the formation of a modified cilium structure whose function is unknown. In the present investigation, characteristic ultrastructural features of the modified cilium structure and its relationship to the Golgi apparatus and the axon terminal are presented. A function for the modified cilium structure is discussed.

Primary Postnatal Dorsal Root Ganglion Culture from Conventionally Slaughtered Calves

“…The majority of cells had long slender bipolar cytoplasmic processes and a central oval nucleus that expressed S100 protein, GFAP and vimentin indicating Satellite/Schwann cell origin. Additionally, TEM revealed the presence of cilia, exhibiting a characteristic microtubular cytoskeleton and extending from a ciliary pocket [26], confirming neuroectodermal origin (S6D Fig) [27, 28]. These cells followed the course of neurites and enclosed them.…”

Slow or fast: Implications of myofibre type and associated differences for manifestation of neuromuscular disorders

“…291 Primary cilia are present on quiescent and activated satellite cells 292 and Schwann cells, 293 with modified cilia on perisynaptic Schwann cells. 294 Insight into the neuromuscular roles for crosstalk of cilia and EV signalling related to slow and fast motoneurons and myofibres is likely to rapidly expand.…”

“…These muscle and nerve cellular interactions may involve the primary cilia since it is well‐documented that cilia interact with the local environment for mechanosensing and can also modulate the ECM environment, with cilia attracting increasing attention as a key signalling hub in the peripheral nervous system for neuronal regulation and regeneration 291 . Primary cilia are present on quiescent and activated satellite cells 292 and Schwann cells, 293 with modified cilia on perisynaptic Schwann cells 294 . Insight into the neuromuscular roles for cross‐talk of cilia and EV signalling related to slow and fast motoneurons and myofibres is likely to rapidly expand.…”