A novel missense creatine mutant of CaBP4, c.464G>A (p.G155D), associated with autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE), reduces the expression of CaBP4

作者：Guo, Yuxiong; Miao, Qinfei; Zhang, Yuxin; Wang, Chun; Liang, Mingjuan; Li, Xueping; Qiu, Weifeng; Shi, Gangan; Zhai, Qiongxiang; Chen, Zhihong^*

来源：Translational Pediatrics, 2022, 11(3): 396-402.

DOI：10.21037/tp-22-54

• Ca(2+-)binding protein 4 (CaBP4)
• epilepsy
• autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE)
• real-time polymerase chain reaction (RT-PCR)
• Western blot

Background: CaBP4 encodes Ca2+-binding protein 4, a neuronal Ca2+-binding protein that participates in many cellular processes by regulating the concentration of free Ca2+ ions. De novo CaBP4 variants have been identified as a cause of congenital stationary night blindness (CSNB). However, we recently reported a 4-generation pedigree with 11 individuals diagnosed with autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE) that were validated with only one novel missense mutation, c.464G>A (p.G155D), in CaBP4. De novo CaBP4 variants have never been reported to be related with ADNFLE. This study aimed to identify whether c.464G>A (p.G155D) in CaBP4 reduced the expression of CaBP4. @@@ Methods: In vitro experiments using recombinant protein expressed in human neuron cells were utilized in this study. Real-time polymerase chain reaction (RT-PCR) was performed to evaluate the effect of c.464G>A on CaBP4 mRNA expression. Western blot was performed to assess the effect of c.464G>A on CaBP4 protein expression. @@@ Results: According to the RT-PCR and Western blot results, c.464G>A (p.G155D) was associated with an increased expression of CaBP4 mRNA and a reduced expression of CaBP4 protein. @@@ Conclusions: These results reveal that c.464G>A (p.G155D) in CaBP4 reduced the expression of CaBP4 by reducing the stability of the CaBP4 protein. Mutations in the CaBP4 gene may be associated with ADNFLE.

• 单位
  汕头大学; 南方医科大学; 广东省人民医院