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Pristionchus – Molecular Toolkit

Pristionchus pacificus is an attractive model organism for laboratory studies based on several technical features:

  1. worms can indefinitely been grown in the lab on E. coli bacteria.
  2. they complete their life cycle in 4 days at 20° C.
  3. P. pacificus is a self-fertilizing hermaphrodite.


The following tools have been established over the years that allow mechanistic studies in this nematode:

  1. Forward and reverse genetic tools are well-established (Tian et al., 2008)
  2. Microinjection of DNA results in DNA-mediated transformation (Schlager et al., 2009)
  3. The CRISPR-Cas9 system works efficiently for genome editing (Witte et al., 2015)
  4. The P. pacificus genome has been sequenced a decade ago (Diederich et al., 2008)
  5. A de novo assembly from single molecule sequencing provided a chromosome-scale genome assembly of P. pacificus (submitted)


We are permanently improving our methodological platform in the following areas:

Scientists involved:

  • Dr. Christian Rödelsperger
  • Waltraud Röseler, Technician
  • Hanh Witte, Technician

Selected References:

Sun, S., Rödelsperger, C. & R. J. Sommer (2021): Single worm transcriptomics isentifies a developmental core network of oscillating genes with deep conservation across nematodes. Genome Research, 31, 1590-1601.

Athanasouli, M., Witte, H., Weiler, C., Loschko, T., Eberhardt, G., Sommer, R. J. and C. Roedelsperger (2020): Comprataive genomics and community curation further improve gene annotation in te nematode Pristionchus pacificus. BMC Genomics, 21, 708.

Han, Z., Lo, W.-S., Lightfoot, J. W., Witte, H., Sun, S. & R. J. Sommer (2020): Improving trangenesis efficiency and CRISPR-associated tools through codon optimization and native intron addition in nematodes. Genetics, 216, 947-956.

Witte, H., Moreno, E., Rödelsperger, C., Kim, J., Kim, J.-S., Streit A. & Sommer, R. J. (2015): Gene inactivation using the CRISPR/Cas9 system in the nematode Pristionchus pacificus. Dev Genes & Evol., 225, 55-62.

Rödelsperger, C., Neher, R. A., Weller, A., Eberhardt, G., Witte, H., Mayer, W., Dieterich, C. & Sommer, R. J. (2014): Characterization of genetic diversity in the nematode Pristionchus pacificus from population-scale resequencing data. Genetics, 196, 1153-1165.

Schlager, B., Wang, X., Braach, G. & Sommer, R. J. (2009): Molecular cloning of a dominant roller mutant and establishment of DNA-mediated transformation in the nematode model Pristionchus pacificus. Genesis, 47, 300-304.

Dieterich, C., Clifton, S. W., Schuster, L. N.,Chinwalla,  A., Delehaunty, K., Dinkelacker, I., Fulton, L., Fulton, R., Godfrey, J., Minx, P., Mitreva, M., Roeseler, W., Tian, H., Witte, H., Yang, S. P., Wilson, R. K., Sommer,  R. J. (2008): The Pristionchus pacificus genome provides a unique perspective on nematode lifestyle and parasitism. Nature Genetics, 40, 1193-1198.

Tian, H, Schlager, B., Xiao, H. & Sommer, R. J. (2008): Wnt signaling induces vulva development in the nematode Pristionchus pacificus. Current Biology, 18, 142-146.