Morpholino

Morpholino oligos or short morpholinos are nucleic acid analogs that are used as tools in molecular biology to achieve a knockdown of genes. The synthetic molecules, which are synthesized by structurally modified nucleic acid building blocks are also referred to as PMOS ( phosphorodiamidate morpholino oligo). They are used in anti-sense RNA experiments and inhibited by binding to complementary mRNA, either the translation or splicing of pre-mRNA and hence the formation of a protein.

Their effect is thus comparable to the siRNAs, but morpholinos have a higher stability and longer half-life, because they are not RNase substrates and are therefore degraded less rapidly than antisense RNA. Disadvantage is that transfection of morpholinos is difficult, therefore, is usually resorted to injection. Especially in the zebrafish model system morpholinos are frequently used to analyze the function of genes in the early embryonic development.

The synthetic oligos were developed in 1997 by James E. Summerton (Gene Tools, LLC ) and Dwight D. Weller (AVI BioPharma Inc.).