Sala C, Francolini M, Di Mauro D, Fumagalli G
CNR Center of Cellular and Molecular Pharmacology, Department of Medical Pharmacology, University of Milano, Milan, Italy.
Neurosci Lett. 1998 Oct 30;256(1):1-4. doi: 10.1016/s0304-3940(98)00752-6.
During neuromuscular junction maturation, the rapidly degrading receptors (Rr; t1/2 approximately equal to 1 day) are replaced by metabolically stable molecules (Rs; t1/2 approximately equal to 10 days). Rr and Rs do not interconvert, are differently regulated after denervation in adult muscle and are endowed of unique responses to stabilizing agents. In cultured rat myotubes all the epsilon subunit-containing acetylcholine receptors (epsilon-AchRs) are of the Rs type. In the present study we show that Rs exist also in absence of epsilon-AChR and that nonepsilon-(presumably gamma-)AChRs can be included in the Rs pool when epsilon-AChR expression is low. The data indicate that Rs metabolic properties are independent of AChR subunit composition and that epsilon subunit is a signal to efficiently sort AChR molecules to the Rs pool.
在神经肌肉接头成熟过程中，快速降解的受体（Rr；半衰期约为1天）被代谢稳定的分子（Rs；半衰期约为10天）所取代。Rr和Rs不能相互转化，在成年肌肉去神经支配后受到不同的调节，并且对稳定剂有独特的反应。在培养的大鼠肌管中，所有含ε亚基的乙酰胆碱受体（ε-AchRs）都是Rs型。在本研究中，我们表明在没有ε-AChR的情况下Rs也存在，并且当ε-AChR表达较低时，非ε-（可能是γ-）AChRs可以包含在Rs池中。数据表明Rs的代谢特性与AChR亚基组成无关，并且ε亚基是将AChR分子有效分选到Rs池的信号。
