QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

HOME  |   SEARCH  |   ARCHIVE  |   SUBSCRIBE  |   CONTACT  |   HELP

This Article Full Text (PDF) Submit an eLetter Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Jones, S. M. Articles by Ribera, A. B. Search for Related Content PubMed PubMed Citation Articles by Jones, S. M. Articles by Ribera, A. B.

 Previous Article  |  Next Article 

Journal of Neuroscience, Vol 15, 2867-2874, Copyright © 1995 by Society for Neuroscience

ARTICLE

Overexpression of potassium channel RNA: in vivo development rescues neurons from suppression of morphological differentiation in vitro

SM Jones, AD Hofmann, JL Lieber and AB Ribera
Department of Physiology, University of Colorado Health Sciences Center, Denver 80262, USA.

Neuronal differentiation often proceeds differently in vitro than it does in vivo. Previous work demonstrated that overexpression of potassium channel RNA reduces the number of morphologically identifiable neurons that appear in cultures prepared from neural plate stage (17-1/2 hr) embryos (Jones and Ribera, 1994). Here, we report that morphological differentiation of neurons in situ is only slightly affected by overexpression of potassium channels. Endogenous factors appear to compensate for the effect of channel overexpression. Consistent with this view, when cultures are prepared from older neural tube embryos (22-24 hr), more neurons containing excess potassium channel RNA differentiate morphologically in vitro. Exposure in situ to a rapid intracellular calcium chelator, but not to tetrodotoxin, omega- conotoxin or a slow calcium chelator, prevents the compensation provided by extended development in vivo. Typically, RNA overexpression is limited to half of the embryo in order to provide an internal control. However, when potassium channel RNA is overexpressed throughout the embryo, few neurons differentiate morphologically in vitro, even if cultures are prepared from older neural tube embryos. Thus, recovery is possible if a minimum of 5 hr of further development in vivo is allowed under conditions in which rapid elevations of intracellular calcium are permitted and half of the nervous system has normal levels of potassium channel RNA. These results suggest that different or additional mechanisms operate in situ than in vitro to promote morphological differentiation of neurons.

This article has been cited by other articles:

				M. N. Nitabach, Y. Wu, V. Sheeba, W. C. Lemon, J. Strumbos, P. K. Zelensky, B. H. White, and T. C. Holmes Electrical Hyperexcitation of Lateral Ventral Pacemaker Neurons Desynchronizes Downstream Circadian Oscillators in the Fly Circadian Circuit and Induces Multiple Behavioral Periods J. Neurosci., January 11, 2006; 26(2): 479 - 489. [Abstract] [Full Text] [PDF]

				W. J. Moody and M. M. Bosma Ion Channel Development, Spontaneous Activity, and Activity-Dependent Development in Nerve and Muscle Cells Physiol Rev, July 1, 2005; 85(3): 883 - 941. [Abstract] [Full Text] [PDF]

				J. S. Smith, C. A. Iannotti, P. Dargis, E. P. Christian, and J. Aiyar Differential Expression of KCNQ2 Splice Variants: Implications to M Current Function during Neuronal Development J. Neurosci., February 15, 2001; 21(4): 1096 - 1103. [Abstract] [Full Text] [PDF]

Home  |   Search  |   Archive  |   Subscribe  |   Contact  |   Help