Hoxful Monsters

In the era of Genomics as new genes are always being discovered by virtue of complete genome sequences of various organisms,there is an ever increasing need for more tools for functional validation.In order to assign functions to the new genes discovered ,reverse genetics techniques are becoming increasingly attractive as they offer the opportunity to choose the gene of interest from database and in quick time one can assign a function to that gene.With the rise in demand for knocking down gene function in the field of developmental biology ,scientists were always looking for something really potent.This is where Morpholinos antisense oligos comes into picture, which was initially used as for clinical therapeutic applications.

Morpholino oligos are chains of about 25 Morpholino subunits. Each subunit is comprised of a nucleic acid base, a morpholine ring and a non-ionic phosphorodiamidate intersubunit linkage.They act by blocking translation by binding to 5′ UTR region and prevent the ribosomal initiation complex from binding to the cognate mRNA. Morpholinos can also enter the nucleus and base pair with a “pre-mRNA” before it has been post-transcriptionally modified. It can also modify splicing of mRNA or by inhibiting mRNA maturation and activity.Morpholinos beacuse of thier high affinity to bind mRNA and being very specific as well yields consistent results.They are very stable in cells and do not induce innate immune response.The other properties of high Solubility, Non-ionic and RNase-H Independent adds to its advantage as knock down tool.

Morpholinos are since then used by researchers in a range of model organisms,including sea urchin, Ciona,Xenopus laevis ,Xenopus tropicalis, zebrafish,Sea urchins,chick and mouse.It has got some disadvantages as well but these are part and parcel of any technique making Morpholinos as another great addition to the reverse genetics tool armory,which also includes powerful RNAi technology.
In the year 2001, an entire issue of the journal “Genesis” was dedicated to articles studying gene function in development using Morpholinos.
In true sense Morpholinos along with RNAi technology making Sense out of antisense in the field of Developmental biology.