The functional study of Wdhd1 in mouse early embryogenesis

• Main Authors: Kuo-Hung Lee, 李國宏
• Other Authors: You-Tzung Chen
• Format: Others
• Language: zh-TW
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/nh7fe8

碩士 === 國立臺灣大學 === 基因體暨蛋白體醫學研究所 === 107 === WD Repeat and HMG-Box DNA Binding Protein 1(WDHD1) is an evolutionary conserved protein in eukaryotes. Previous research indicates that WDHD1 plays a crucial role in initiation and elongation of DNA replication. WDHD1 acts as a hub to help the formation of DNA replication-related complexes (e.g., pre-replication complex and replication protein complex) and it also ensures efficient DNA replication. WDHD1 is required for gnome integrity maintenance. Phylogenetic analysis revealed that, compared to non-vertebrate eukaryotes, vertebrate WDHD1 not only possesses a WD40 domain and a SepB domain but also has an additional HMG-box domain at its C-terminus. WDHD1 deficiency in human cell causes cell cycle delays and abnormal chromosome segregations. In order to study its biological function in mammal in vivo, we use the CRISPR/Cas9 gene editing tool to generate Wdhd1 deficient mice. In addition, we are going to study the HMG-box domain of Wdhd1. A Wdhd1 exon1 frameshift mutation (c.13delinsTGAGA) in the mouse was generated and found that this mutant allele can cause embryonic lethality when it is bred to homozygosity and discovered abnormal phenotype of embryos at the stage of E7.5 and E8.5. Wdhd1 c.13delinsTGAGA homozygous mutant embryos showed apparently normal growth during the pre-implantation stage, but retarded growth at E7.5. Further investigation showed that the cell proliferation ratio decreased and also showed apoptosis signal at E7.5 homozygous mutant embryos. Taken together, these findings revealed that Wdhd1 is essential for mouse embryogenesis. Once Wdhd1 is defective, it causes abnormal growth of the embryo at E7.5-E10.5 and eventually leads to embryonic lethality.