Department of Biomedical Science, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Aichi, Japan.
Department of Comparative and Experimental Medicine, Graduate School of Medical Sciences, Nagoya City University, 1 Kawasumi Mizuho-cho, Mizuho-ku, Nagoya, Aichi, Japan.
Mol Cell Neurosci. 2019 Oct;100:103401. doi: 10.1016/j.mcn.2019.103401. Epub 2019 Sep 3.
Reelin plays important roles in regulating neuronal development, modulating synaptic function, and counteracting amyloid β toxicity. A specific proteolytic cleavage (N-t cleavage) of Reelin abolishes its biological activity. We recently identified ADAMTS-3 (a disintegrin and metalloproteinase with thrombospondin motifs 3) as the major N-t cleavage enzyme in the embryonic and early postnatal brain. The contribution of other proteases, particularly in the postnatal brain, has not been demonstrated in vivo. ADAMTS-2, -3 and -14 share similar domain structures and substrate specificity, raising the possibility that ADAMTS-2 and -14 may cleave Reelin. We found that recombinant ADAMTS-2 protein expressed in cultured cell lines cleaves Reelin at the N-t site as efficiently as ADAMTS-3 while recombinant ADAMTS-14 hardly cleaves Reelin. The disintegrin domain is necessary for the Reelin-cleaving activity of ADAMTS-2 and -3. ADAMTS-2 is expressed in the adult brain at approximately the same level as ADAMTS-3. We generated ADAMTS-2 knockout (KO) mice and found that ADAMTS-2 significantly contributes to the N-t cleavage and inactivation of Reelin in the postnatal cerebral cortex and hippocampus, but much less in the cerebellum. Therefore, it was suggested that ADAMTS-2 can be a therapeutic target for adult brain disorders such as schizophrenia and Alzheimer's disease.
Reelin 在调节神经元发育、调节突触功能和对抗淀粉样 β 毒性方面发挥着重要作用。 Reelin 的特定蛋白水解切割(N 端切割)会使其丧失生物学活性。我们最近发现 ADAMTS-3(含血栓反应蛋白基序的解整合素和金属蛋白酶 3)是胚胎和新生后脑中主要的 N 端切割酶。其他蛋白酶的作用,特别是在出生后的大脑中,尚未在体内得到证明。ADAMTS-2、-3 和 -14 具有相似的结构域结构和底物特异性,这使得 ADAMTS-2 和 -14 可能切割 Reelin。我们发现,在培养的细胞系中表达的重组 ADAMTS-2 蛋白可像 ADAMTS-3 一样有效地在 N 端切割 Reelin,而重组 ADAMTS-14 几乎不切割 Reelin。解整合素结构域是 ADAMTS-2 和 -3 切割 Reelin 的必需结构域。ADAMTS-2 在成年脑中的表达水平与 ADAMTS-3 大致相同。我们生成了 ADAMTS-2 敲除(KO)小鼠,并发现 ADAMTS-2 显著促进了出生后大脑皮质和海马体中 Reelin 的 N 端切割和失活,但在小脑体中作用较小。因此,ADAMTS-2 可能成为精神分裂症和阿尔茨海默病等成人脑部疾病的治疗靶点。