Moya K L, Confaloni A M, Allinquant B
CNRS URA 1285, Orsay, France.
J Neurochem. 1994 Nov;63(5):1971-4. doi: 10.1046/j.1471-4159.1994.63051971.x.
We have shown previously that the amyloid precursor protein (APP) is synthesized in retinal ganglion cells and is rapidly transported down the axons, and that different molecular weight forms of the precursor have different developmental time courses. Some APP isoforms contain a Kunitz protease inhibitor (KPI) domain, and APP that lacks the KPI domain is considered the predominant isoform in neurons. We now show that, among the various rapidly transported APPs, a 140-kDa isoform contains the KPI domain. This APP isoform is highly expressed in rapidly growing retinal axons, and it is also prominent in adult axon endings. This 140-kDa KPI-containing APP is highly sulfated compared with other axonally transported isoforms. These results show that APP with the KPI domain is a prominent isoform synthesized in neurons in vivo, and they suggest that the regulation of protease activity may be an important factor during the establishment of neuronal connections.
我们先前已经表明，淀粉样前体蛋白（APP）在视网膜神经节细胞中合成，并迅速沿轴突运输，而且前体的不同分子量形式具有不同的发育时间进程。一些APP同工型含有一个库尼茨蛋白酶抑制剂（KPI）结构域，而缺乏KPI结构域的APP被认为是神经元中的主要同工型。我们现在表明，在各种快速运输的APP中，一种140 kDa的同工型含有KPI结构域。这种APP同工型在快速生长的视网膜轴突中高度表达，在成年轴突末端也很突出。与其他轴突运输的同工型相比，这种含有140 kDa KPI的APP高度硫酸化。这些结果表明，具有KPI结构域的APP是体内神经元中合成的一种突出同工型，并且表明蛋白酶活性的调节可能是神经元连接建立过程中的一个重要因素。
