title: The defective expression of gtpbp3 related to tRNA modification alters the mitochondrial function and development of zebrafish.
abstract: Human mitochondrial DNA (mtDNA) mutations have been associated with a wide spectrum of clinical abnormalities. However, nuclear modifier gene(s) modulate the phenotypic expression of pathogenic mtDNA mutations. In our previous investigation, we identified the human GTPBP3 related to mitochondrial tRNA modification, acting as a modifier to influence of deafness-associated mtDNA mutation. Mutations in GTPBP3 have been found to be associated with other human diseases. However, the pathophysiology of GTPBP3-associated disorders is still not fully understood. Here, we reported the generation and characterization of Gtpbp3 depletion zebrafish model using antisense morpholinos. Zebrafish gtpbp3 has three isoforms localized at mitochondria. Zebrafish gtpbp3 is expressed at various embryonic stages and in multiple tissues. In particular, the gtpbp3 was expressed more abundantly in adult zebrafish ovary and testis. The expression of zebrafish gtpbp3 can functionally restore the growth defects caused by the mss1/gtpbp3 mutation in yeast. A marked decrease of mitochondrial ATP generation accompanied by increased levels of apoptosis and reactive oxygen species were observed in gtpbp3 knockdown zebrafish embryos. The Gtpbp3 morphants exhibited defective in embryonic development including bleeding, melenin, oedema and curved tails within 5days post fertilization, as compared with uninjected controls. The co-injection of wild type gtpbp3 mRNA partially rescued these defects in Gtpbp3 morphants. These data suggest that zebrafish Gtpbp3 is a structural and functional homolog of human and yeast GTPBP3. The mitochondrial dysfunction caused by defective Gtpbp3 may alter the embryonic development in the zebrafish. In addition, this zebrafish model of mitochondrial disease may provide unique opportunities for studying defective tRNA modification, mitochondrial biogenesis, and pathophysiology of mitochondrial disorders.
authors.affiliation: Institute of Genetics, Zhejiang University and Department of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
authors.forename: Danni
authors.initials: D
authors.lastname: Chen
authors.affiliation: Institute of Genetics, Zhejiang University and Department of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Li
authors.affiliation: Institute of Genetics, Zhejiang University and Department of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
authors.forename: Qingxian
authors.initials: Q
authors.lastname: Yang
authors.affiliation: Institute of Genetics, Zhejiang University and Department of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
authors.forename: Miao
authors.initials: M
authors.lastname: Tian
authors.affiliation: Institute of Genetics, Zhejiang University and Department of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
authors.forename: Zengming
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Institute of Genetics, Zhejiang University and Department of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
authors.forename: Qinghai
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Institute of Genetics, Zhejiang University and Department of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China. Electronic address: yechency@zju.edu.cn.
authors.forename: Ye
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Institute of Genetics, Zhejiang University and Department of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China; Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Zhejiang University, Hangzhou 310058, China; Joining Institute of Genetics and Genomic Medicine between Zhejiang University and University of Toronto, Zhejiang University, Hangzhou, Zhejiang, China. Electronic address: gminxin88@zju.edu.cn.
authors.forename: Min-Xin
authors.initials: MX
authors.lastname: Guan
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D017124:Conserved Sequence; D019204:GTP-Binding Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D006160:Guanosine Triphosphate / Q000378:metabolism; D006801:Humans; D008928:Mitochondria / Q000378:metabolism*; D008958:Models, Molecular; D009928:Organ Specificity; D000072417:Protein Domains; D012343:RNA, Transfer / Q000235:genetics*; D015027:Zebrafish / Q000235:genetics* / Q000254:growth & development* / Q000378:metabolism; D029961:Zebrafish Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism
chemical_list: D029961:Zebrafish Proteins; D006160:Guanosine Triphosphate; D012343:RNA, Transfer; D019204:GTP-Binding Proteins; C000623197:Gtpbp3 protein, zebrafish
keywords: Antisense morpholinos; GTP binding protein 3; Mitochondrial deficiency; Zebrafish model