If I am going to transform a plasmid into a bacterium, which will then be fed to a C. elegans, the expression vector needs to be bacterial correct? The other option is to have a worm expression vector, but I just wanted to make sure that I was correct in my thinking. Thank you.

  • 4
    $\begingroup$ Are you trying to express the plasmid's contents in C. elegans, so that its cells are producing the gene product, or do you want the bacteria to produce the gene product so that C. elegans can consume the protein? $\endgroup$
    – MattDMo
    Nov 3 '15 at 18:54
  • $\begingroup$ I am trying to express the plasmid's contents in c. Elegans so it's cells are producing the product $\endgroup$ Nov 4 '15 at 13:56
  • $\begingroup$ C. elegans do not express the genes of organisms they eat. To create transgenic worms you either need to microinject purified DNA, or use biolistic transformation (using microparticles coated with DNA). Ingestion does work if you are trying to use RNAi to knockdown expression of a C. elegans gene, but in that case the double-stranded RNA is expressed from a bacterial expression vector. You can also synthesize dsRNA in vitro and soak the worms in that, which I believe also enters when the worms "eat." $\endgroup$
    – mdperry
    Nov 5 '15 at 12:01

You are trying to express the plasmid in C. elegans, so it should be a worm expression vector and promoter. Otherwise, it will be expressed in the host bacteria, but not in the worm, so you won't get the phenotype you're looking for.

One thing you can do is add a bacterial origin of replication to the vector (if one isn't already present) so the bacteria produce multiple copies of the plasmid after transformation. Otherwise, the amount of plasmid consumed by the worms will be rather low.

  • $\begingroup$ Perfect, thanks a lot for your advice, I appreciate it. $\endgroup$ Nov 4 '15 at 15:59

Not the answer you're looking for? Browse other questions tagged or ask your own question.