signal peptide - (Jan/07/2006 )

hi,

please anyone help me..
what is signal peptide? its fucntions?
i tried to expressed recomb protein from SAG-1 gene (Toxoplasma Surface Antigen), which has no intron; but i failed. was it anything to do with signal proteins, for there is one in that gene.

thannk you very much
didi

Hello,

the function of signal peptide is to target the protein to where will be post-transcriptional modifications, to target the surface protein to the membrane, to target to enzymes for palmitoylation...

I use to work with bacterial proteins... but I would say that for non bacterial proteins, you cut yourself the signal peptide to let the bacteria synthetize the mature protein (because bacteria do not have same enzymes than eucaryote cells and would not cut it). I mean you insert the DNA corresponding to the mature protein, without the signal peptide.
but you may better check this information.

maybe your protein is not well refolded, and you will find it in the inclusion bodies?

good luck

laurence