Posttranslational regulation of Ca(2+)-activated K+ currents by a target-derived factor in developing parasympathetic neurons.
Macroscopic IK[Ca is not expressed in normal levels in chick ciliary ganglion (CG) neurons prior to synapse formation with target tissues, or in neurons developing in vitro or in situ in the absence of target tissues. Here, two chick CG slo partial cDNAs encoding IK[Ca channels were isolated, cloned, and sequenced. Both slo transcripts were readily detected in developing CG neurons prior to or in the absence of target tissue interactions. When CG neurons developed in vitro in the presence of target tissue (iris) extracts, a normal whole-cell IK[Ca was expressed. These effects did not require protein synthesis, and the activity was detectable throughout the stages of synapse formation in the iris. The active component has an apparent molecular weight of 40-60 kDa.
Subramony
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Programs in Neuroscience and Molecular Biophysics, Florida State University, Tallahassee 32306, USA.
Raucher
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Dryer
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Dryer
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D000595:Amino Acid Sequence; D000818:Animals; D002118:Calcium / Q000502:physiology*; D016922:Cellular Senescence; D002642:Chick Embryo; D018076:DNA, Complementary / Q000235:genetics; D004553:Electric Conductivity; D005726:Ganglia, Parasympathetic / Q000166:cytology / Q000196:embryology / Q000502:physiology*; D007498:Iris / Q000737:chemistry / Q000196:embryology; D008969:Molecular Sequence Data; D009474:Neurons / Q000187:drug effects / Q000502:physiology*; D011188:Potassium / Q000502:physiology*; D015221:Potassium Channels / Q000235:genetics; D011499:Protein Processing, Post-Translational; D014020:Tissue Extracts / Q000494:pharmacology; D014158:Transcription, Genetic
D018076:DNA, Complementary; D015221:Potassium Channels; D014020:Tissue Extracts; D011188:Potassium; D002118:Calcium