Echinobase will be undergoing a hardware update June 13 and 14, 2023 and therefore will be unavailable those days.

We apologize for the inconvenience.

Click on this message to dismiss it.
Click here to close Hello! We notice that you are using Internet Explorer, which is not supported by Echinobase and may cause the site to display incorrectly. We suggest using a current version of Chrome, FireFox, or Safari.


Morpholino oligos (MOs) are short, antisense oligos made of modified nucleotides. MOs can knock down gene expression by inhibiting mRNA translation, blocking RNA splicing, or inhibiting miRNA activity and maturation. MOs are effective knockdown tools used in developmental biology experiments and RNA-blocking reagents for cells in culture. MOs do not degrade their RNA targets, but instead act via a steric blocking mechanism RNAse H-independent manner. They remain stable in cells and do not induce immune responses. Microinjection of MOs in early Xenopus embryos can suppress gene expression in a targeted manner.

Like all antisense approaches, different MOs can have different efficiencies and may cause off-target, non-specific effects. Often, several MOs need to be tested to find an effective target sequence. Rigorous controls are used to demonstrate specificity, including:

  • Phenocopy of genetic mutation
  • Verification of reduced protein by western or immunostaining
  • mRNA rescue by adding back a mRNA immune to the MO
  • use of 2 different MOs (translation blocking and splice blocking)