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Expression of frequenin at the frog (Rana) neuromuscular junction, muscle spindle and nerve
M J Werle1, J Roder, A Jeromin
1Department of Anatomy and Cell Biology, The University of Kansas Medical Center, 3901 Rainbow Boulevard, Kansas City, 66160, Kansas, USA. mwerle@kumc.edu
Abstract:
Frequenin is a calcium binding protein previously implicated in the regulation of neurotransmission in Drosophila and Xenopus. We have used the frog (Rana pipiens) to study the localization and regulation of expression of frequenin-like molecules in the vertebrate peripheral nervous system. Affinity purified antibodies to frequenin recognize molecules in the neuromuscular junction, axons in the peripheral nerve, and neuronal processes in muscle spindles. Western blots of endplate regions, peripheral nerve, and brain, resulted in the labelling of a single 24 kDa band, which is the expected size for frequenin. These results suggest that frequenin expression is high in the frog peripheral nervous system, and may reflect a function for frequenin in synaptic transmission in vertebrates.
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