PUBLICATION

Design and Microinjection of Morpholino Antisense Oligonucleotides and mRNA into Zebrafish Embryos to Elucidate Specific Gene Function in Heart Development

Authors
Zakaria, Z.Z., Eisa-Beygi, S., Benslimane, F.M., Ramchandran, R., Yalcin, H.C.
ID
ZDB-PUB-220831-11
Date
2022
Source
Journal of visualized experiments : JoVE   (186): (Journal)
Registered Authors
Eisa-Beygi, Shahram, Ramchandran, Ramani
Keywords
none
MeSH Terms
  • Animals
  • Embryo, Nonmammalian
  • Gene Knockdown Techniques
  • Morpholinos/genetics
  • Morpholinos/pharmacology
  • Oligonucleotides, Antisense*/genetics
  • Phenotype
  • RNA, Messenger/genetics
  • Zebrafish*/genetics
  • Zebrafish Proteins/genetics
PubMed
36036621 Full text @ J. Vis. Exp.
Abstract
The morpholino oligomer-based knockdown system has been used to identify the function of various gene products through loss or reduced expression. Morpholinos (MOs) have the advantage in biological stability over DNA oligos because they are not susceptible to enzymatic degradation. For optimal effectiveness, MOs are injected into 1-4 cell stage embryos. The temporal efficacy of knockdown is variable, but MOs are believed to lose their effects due to dilution eventually. Morpholino dilution and injection amount should be closely controlled to minimize the occurrence of off-target effects while maintaining on-target efficacy. Additional complementary tools, such as CRISPR/Cas9 should be performed against the target gene of interest to generate mutant lines and to confirm the morphant phenotype with these lines. This article will demonstrate how to design, prepare, and microinject a translation-blocking morpholino against hand2 into the yolk of 1-4 cell stage zebrafish embryos to knockdown hand2 function and rescue these "morphants" by co-injection of mRNA encoding the corresponding cDNA. Subsequently, the efficacy of the morpholino microinjections is assessed by first verifying the presence of morpholino in the yolk (co-injected with phenol red) and then by phenotypic analysis. Moreover, cardiac functional analysis to test for knockdown efficacy will be discussed. Finally, assessing the effect of morpholino-induced blockage of gene translation via western blotting will be explained.
Genes / Markers
Figures
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping