title: NXT2 is required for embryonic heart development in zebrafish.
abstract: BACKGROUND
  NXT2 is a member of NXT family proteins that are generally involved in exporting nuclear RNA in eukaryotic cells. It is not known if NXT2 has any function in specific biological processes.
  
  
  RESULTS
  A zebrafish mutant exhibiting specific heart defects during embryogenesis was generated by animal cloning-mediated retroviral insertions. Molecular analysis indicated that the mutant phenotype was caused by a disruption of NXT2. Whole-mount RNA in situ hybridization showed that NXT2 transcripts were clearly detectable in embryonic heart as well as other tissues. Further analysis revealed that expression level of one form of alternative splicing NXT2 mRNA transcripts was significantly reduced, resulting in deficient myocardial cell differentiation and the malformation of cardiac valve at the atrioventricular boundary. The defects could be reproduced by morpholino anti-sense oligo knockdown of NXT2.
  
  
  CONCLUSIONS
  NXT2 has a critical role in maintaining morphogenetic integrity of embryonic heart in vertebrate species.
authors.affiliation: Department of Molecular, Cell, and Developmental Biology, University of California, Los Angeles, California 90095, USA. haigenh@ucla.edu
authors.forename: Haigen
authors.initials: H
authors.lastname: Huang
authors.forename: Bo
authors.initials: B
authors.lastname: Zhang
authors.forename: Parvana A
authors.initials: PA
authors.lastname: Hartenstein
authors.forename: Jau-nian
authors.initials: JN
authors.lastname: Chen
authors.forename: Shuo
authors.initials: S
authors.lastname: Lin
mesh_terms: D021581:Active Transport, Cell Nucleus; D017398:Alternative Splicing; D000818:Animals; D002454:Cell Differentiation / Q000235:genetics; D019976:Cloning, Organism; D004251:DNA Transposable Elements; D004489:Edema, Cardiac / Q000235:genetics / Q000473:pathology; D006321:Heart / Q000196:embryology* / Q000502:physiology; D006330:Heart Defects, Congenital / Q000235:genetics / Q000473:pathology; D006351:Heart Valves / Q000473:pathology; D009206:Myocardium / Q000737:chemistry / Q000166:cytology / Q000473:pathology; D049790:Nuclear Export Signals / Q000235:genetics / Q000502:physiology*; D010641:Phenotype; D016372:RNA, Antisense; D012333:RNA, Messenger / Q000032:analysis / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014158:Transcription, Genetic; D015027:Zebrafish / Q000196:embryology* / Q000235:genetics; D029961:Zebrafish Proteins / Q000235:genetics / Q000502:physiology
chemical_list: D004251:DNA Transposable Elements; C507610:NXT2 protein, zebrafish; D049790:Nuclear Export Signals; D016372:RNA, Antisense; D012333:RNA, Messenger; D029961:Zebrafish Proteins