The present address of Dr. S. Sato is Sugita Eye Hospital, Nagoya 460, Japan.
Transcription and Motoneuron Size
Article first published online: 23 NOV 2002
Journal of Neurochemistry
Volume 63, Issue 5, pages 1609–1615, November 1994
How to Cite
Sato, S., Burgess, S. B. and McIlwain, D. L. (1994), Transcription and Motoneuron Size. Journal of Neurochemistry, 63: 1609–1615. doi: 10.1046/j.1471-4159.1994.63051609.x
- Issue published online: 23 NOV 2002
- Article first published online: 23 NOV 2002
- Received June 7, 1993; revised manuscript received April 8, 1994; accepted April 12, 1994.
- Nuclear size;
- Spinal motoneuron;
- Motoneuron size;
Abstract: Nuclear size and total RNA synthesis were compared in single lumbar motoneurons isolated from the grass frog. Transcription was found to correlate significantly, but not exclusively, with nuclear area or volume over a wide range of nuclear size, the largest nuclei having the highest mean transcriptional activity. Flow cytometric analysis of propidium iodide-stained nuclei excluded polyploidy or polyteny as an explanation for the increased transcription, but left open the possibility of a small increase in DNA with increasing nuclear size. Alternatively, motoneurons may increase transcription and nuclear size without increasing their DNA content, possibly by increasing the proportion of dispersed chromatin (euchromatin). These two mechanisms for size-related changes in RNA synthesis in motoneurons present an interesting contrast to mechanisms used by many other large animal cells.