The readthrough of premature termination codon (PTC) by ribosome sometimes produces full-length proteins. We previously reported a readthrough of PTC of glycosyltransferase gene B4GALNT1 with hereditary spastic paraplegia (HSP). Here we featured the readthrough of B4GALNT1 of two mutants, M4 and M2 with PTC by immunoblotting and flow cytometry after transfection of B4GALNT1 cDNAs into cells. Immunoblotting showed a faint band of full-length mutant protein of M4 but not M2 at a similar position with that of wild-type B4GALNT1. AGC sequences at immediately before and after the PTC in M4 were critical for the readthrough. Treatment of cells transfected with mutant M4 cDNA with aminoglycosides resulted in increased readthrough of PTC. Furthermore, treatment of transfectants of mutant M2 cDNA with G418 also resulted in the induction of readthrough of PTC. Both M4 and M2 cDNA transfectants showed increased/induced bands in immunoblotting and GM2 expression in a dose-dependent manner of aminoglycosides. Results of mass spectrometry supported this effect. Here, we showed for the first time the induction and/or enhancement of the readthrough of PTCs of B4GALNT1 by aminoglycoside treatment, suggesting that aminoglycosides are efficient for patients with HSP caused by PTC of B4GALNT1, in which gradual neurological disorders emerged with aging.

中文翻译：

---

氨基糖苷类是诱导遗传性痉挛性截瘫家族中突变B4GALNT1基因中过早终止密码子通读的有效试剂。

核糖体对过早终止密码子（PTC）的读取有时会产生全长蛋白。我们先前报道了遗传性痉挛性截瘫（HSP）的糖基转移酶基因B4GALNT1 PTC的通读。在这里，我们介绍了通过转染B4GALNT1后通过免疫印迹和流式细胞术对两个突变体M4和M2的B4GALNT1进行PTC的通读cDNA进入细胞。免疫印迹显示，在与野生型B4GALNT1相似的位置上，M4全长突变蛋白的条带微弱，但没有M2。M4中PTC之前和之后的AGC序列对于通读至关重要。用氨基糖苷处理用突变M4 cDNA转染的细胞可提高PTC的通读率。此外，用G418处理突变体M2 cDNA的转染子也诱导了PTC的通读。M4和M2 cDNA转染子均以氨基糖苷类剂量依赖性方式在免疫印迹和GM2表达中显示增加/诱导的条带。质谱分析的结果支持了这种效果。在这里，我们首次展示了B4GALNT1的PTC的诱导和/或增强通读通过氨基糖苷治疗，表明氨基糖苷对由B4GALNT1 PTC引起的HSP患者有效，随着年龄的增长逐渐出现神经系统疾病。