| Autor: |
Jaramillo, Fernàn, Vicini, Stefano, Schuetze, Stephen M. |
| Zdroj: |
Nature; September 1988, Vol. 335 Issue: 6185 p66-68, 3p |
| Abstrakt: |
Many proteins are expressed in distinct embryonic and adult forms1,2. However, in most cases we do not know why the embryonic form of proteins is required. This question can be readily addressed for the acetylcholine receptor (AChR) because developmentally specified modifications of this ligand-gated ion channel can be directly related to changes in membrane currents. In developing rat soleus muscle, spontaneous transmitter release causes miniature end-plate currents (m.e.p.cs) to flow into the muscle cell. We show here that these m.e.p.cs in neonatal soleus trigger spontaneous contractions. By injecting m.e.p.cs into young fibres, we showed that only embryonic m.e.p.cs can trigger such contractions; adult m.e.p.cs do not last long enough. Developing muscle fibres must be active for synapse and muscle differentiation. Our experiments indicate that the embryonic form of the AChR is essential for spontaneous contractile activity and may therefore be required for normal neuromuscular development. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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