FERM domain –containing protein 6 identifies a subpopulation of varicose nerve fibers in different vertebrate species

AbstractFERM domain –containing protein 6 (FRMD6) is a member of the FERM protein superfamily, which is evolutionary highly conserved and has recently been identified as an upstream regulator of the conserved growth-promoting Hippo signaling pathway. In clinical studies, the FRMD6 gene is correlated with high signifi cance to Alzheimer’s disease and cognitive impairment implicating a wider role of this protein in the nervous system. Scare data are available on the localization of endogenous FRMD6 in neural tissues. Using a FRMD6-directed antiserum, we detected specific immunoreactivity in varicose nerve fibers in the rat central and peripheral nervous system. FRMD6-immunoreactive (-ir) neurons were found in the sensory ganglia of cranial nerves, which were marked by a pool of labeled cytoplasmic granules. Cross-species comparative studies detected a morphologically identical fiber population and a compar able fiber distribution in tissues from xenopus and human cranial nerves and ganglia. In the spinal cord, FRMD6-ir was detectable in the terminal endings of primary afferent neurons containing substance P (SP). In the rat diencephalon, FRMD6-ir was co-localized with either SP- or arginine vasopressi n–positive fibers in Broca’s diagonal band and the lateral septum. Dense fiber terminals containing both FRMD6-ir and growth hormone-releasing hormone were found in the median eminence. The intimate association of FRMD6 with secretory vesicles was investigated in vitro. In...
Source: Cell and Tissue Research - Category: Cytology Source Type: research