Reverse Genetic Screening Reveals Poor Correlation between Morpholino-Induced and Mutant Phenotypes in Zebrafish

• DOI: 10.1016/j.devcel.2014.11.018
• Publication Date: 2014-12-19T20:51:08Z
• Authors: Fatma O. Kok; Masahiro Shin; Chih-Wen Ni; Ankit Gupta; Ann S. Grosse; Andreas van Impel; Bettina C. Kirchm...; Josi Peterson-Maduro; George Kourkoulis; Ira Male; Dana F. DeSantis; Sarah Sheppard-Ti...; Lwaki Ebarasi; Christer Betsholtz; Stefan Schulte-Me...; Scot A. Wolfe; Nathan D. Lawson
• Keywords: Messenger; Blotting, Western; Oligonucleotides; Embryonic Structures; Real-Time Polymerase Chain Reaction; Morpholinos; Molecular Genetics; 03 medical and health sciences; Research Support, N.I.H., Extramural; Journal Article; Animals; Developmental; RNA, Messenger; Antisense; Zebrafish; Cancer Biology; 0303 health sciences; Deoxyribonucleases; Blotting; Reverse Transcriptase Polymerase Chain Reaction; Research Support, Non-U.S. Gov't; Gene Expression Regulation, Developmental; Oligonucleotides, Antisense; Zebrafish Proteins; Phenotype; Gene Expression Regulation; Gene Knockdown Techniques; Mutation; RNA; Western; Developmental Biology

The widespread availability of programmable site-specific nucleases now enables targeted gene disruption in the zebrafish. In this study, we applied site-specific nucleases to generate zebrafish lines bearing individual mutations in more than 20 genes. We found that mutations in only a small proportion of genes caused defects in embryogenesis. Moreover, mutants for ten different genes failed to recapitulate published Morpholino-induced phenotypes (morphants). The absence of phenotypes in mutant embryos was not likely due to maternal effects or failure to eliminate gene function. Consistently, a comparison of published morphant defects with the Sanger Zebrafish Mutation Project revealed that approximately 80% of morphant phenotypes were not observed in mutant embryos, similar to our mutant collection. Based on these results, we suggest that mutant phenotypes become the standard metric to define gene function in zebrafish, after which Morpholinos that recapitulate respective phenotypes could be reliably applied for ancillary analyses.