Germ line PolIII promoters

I’m trying to express some small RNAs in the germline and have been unsuccessfully trying to find a heterologous PolIII regulated promoter for this purpose. Essentially something similar to the mammalian U1, U6, or H promoters. I’ve tried to look into the C. elegans U1 and U6 genes, but they don’t seem to be very well characterized. Does anyone have any suggestions?

thanks in advance,


We have used the U2-3 promoter to express SL RNAs (about 100 nt). The details are in the following papers:

Harrison, N., Kalbfleisch, A., Connolly, B., Pettitt, J., & Müller, B. (2010). SL2-like spliced leader RNAs in the basal nematode Prionchulus punctatus: New insight into the evolution of nematode SL2 RNAs. RNA (New York, NY), 16(8), 1500–1507. doi:10.1261/rna.2155010

Ferguson, K. C., & Rothman, J. H. (1999). Alterations in the conserved SL1 trans-spliced leader of Caenorhabditis elegans demonstrate flexibility in length and sequence requirements in vivo. Molecular and Cellular Biology, 19(3), 1892–1900.

Best wishes,


yeah, get the cas9 working!

@Jonathan: Perfect, thanks for the references! Exactly what I was looking for, a validated RNAPIII promoter.

@lmu1: Was it that obvious what I was thinking of trying ? :slight_smile: Hope that it works, would be super cool.


You’re the man :wink:
We are cheering for you to figure out how to make it work in worms!