title: Trapping cardiac recessive mutants via expression-based insertional mutagenesis screening.
abstract: BACKGROUND
  Mutagenesis screening is a powerful genetic tool for probing biological mechanisms underlying vertebrate development and human diseases. However, the increased colony management efforts in vertebrates impose a significant challenge for identifying genes affecting a particular organ, such as the heart, especially those exhibiting adult phenotypes on depletion.
  
  
  OBJECTIVE
  We aim to develop a facile approach that streamlines colony management efforts via enriching cardiac mutants, which enables us to screen for adult phenotypes.
  
  
  RESULTS
  The transparency of the zebrafish embryos enabled us to score 67 stable transgenic lines generated from an insertional mutagenesis screen using a transposon-based protein trapping vector. Fifteen lines with cardiac monomeric red fluorescent protein reporter expression were identified. We defined the molecular nature for 10 lines and bred them to homozygosity, which led to the identification of 1 embryonic lethal, 1 larval lethal, and 1 adult recessive mutant exhibiting cardiac hypertrophy at 1 year of age. Further characterization of these mutants uncovered an essential function of methionine adenosyltransferase II, α a (mat2aa) in cardiogenesis, an essential function of mitochondrial ribosomal protein S18B (mrps18b) in cardiac mitochondrial homeostasis, as well as a function of DnaJ (Hsp40) homolog, subfamily B, member 6b (dnajb6b) in adult cardiac hypertrophy.
  
  
  CONCLUSIONS
  We demonstrate that transposon-based gene trapping is an efficient approach for identifying both embryonic and adult recessive mutants with cardiac expression. The generation of a zebrafish insertional cardiac mutant collection shall facilitate the annotation of a vertebrate cardiac genome, as well as enable heart-based adult screens.
authors.affiliation: Department of Biochemistry and Molecular Biology, Mayo Clinic College of Medicine, Rochester, MN 55905, USA.
authors.forename: Yonghe
authors.initials: Y
authors.lastname: Ding
authors.forename: Weibin
authors.initials: W
authors.lastname: Liu
authors.forename: Yun
authors.initials: Y
authors.lastname: Deng
authors.forename: Beninio
authors.initials: B
authors.lastname: Jomok
authors.forename: Jingchun
authors.initials: J
authors.lastname: Yang
authors.forename: Wei
authors.initials: W
authors.lastname: Huang
authors.forename: Karl J
authors.initials: KJ
authors.lastname: Clark
authors.forename: Tao P
authors.initials: TP
authors.lastname: Zhong
authors.forename: Xueying
authors.initials: X
authors.lastname: Lin
authors.forename: Stephen C
authors.initials: SC
authors.lastname: Ekker
authors.forename: Xiaolei
authors.initials: X
authors.lastname: Xu
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D001947:Breeding; D006332:Cardiomegaly / Q000235:genetics*; D004251:DNA Transposable Elements / Q000235:genetics; D004625:Embryo, Nonmammalian / Q000378:metabolism / Q000473:pathology; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D055785:Gene Knockdown Techniques; D005804:Genes, Lethal; D005808:Genes, Recessive; D017930:Genes, Reporter; D005820:Genetic Testing / Q000379:methods*; D005822:Genetic Vectors / Q000235:genetics; D005838:Genotype; D006321:Heart / Q000196:embryology; D008164:Luminescent Proteins / Q000032:analysis / Q000235:genetics; D016254:Mutagenesis, Insertional; D009928:Organ Specificity; D010641:Phenotype; D015027:Zebrafish / Q000196:embryology / Q000235:genetics* / Q000254:growth & development; D029961:Zebrafish Proteins / Q000235:genetics* / Q000502:physiology; D000097573:Red Fluorescent Protein
chemical_list: D004251:DNA Transposable Elements; D008164:Luminescent Proteins; D029961:Zebrafish Proteins; D000097573:Red Fluorescent Protein