Worm Breeder's Gazette 14(2): 23 (February 1, 1996)

These abstracts should not be cited in bibliographies. Material contained herein should be treated as personal communication and should be cited as such only with the consent of the author.

A Cosmid Transgenic Library for C. elegans- An Update

Diana L. Janke1, Jacqueline E. Schein1, Nigel J. O'Neil1, Norman W. Franz1, David L. Baillie1, Ann M. Rose2

1 Institute of Molecular Biology and Biochemisty, Simon Fraser University, Burnaby, BC, CANADA
2 Department of Medical Genetics, University of British Columbia, Vancouver, BC, CANADA

As reported at the 1995 International Worm Meeting, our labs are generating a large number of transgenic C. elegans strains which have been transformed with cosmid DNA sequenced by the C. elegans Genome Sequencing Project (a joint U.S./U.K. effort headed by Drs. R. H. Waterston at Washington University in St. Louis, Missouri, and John Sulston at the MRC Laboratory of Molecular Biology in Cambridge, England). These strains are being made available as a community resource with funding from the Canadian Genome and Associated Technologies Program.
Since our first report in WBG 13(4), we have constructed transgenic strains for over 100 cosmids covering approximately 60% of chromosome III (see figure below). These cosmids contain 3.1 MB of essentially non-overlapping sequence and carry an estimated 483 genes. The annotated sequence for the majority of these cosmids is available from GenBank. While we are attempting to create a "contig" of transgenic strains, the Sequencing Consortium is unable to supply us with DNA for all cosmids. We have prepared DNA for a number of these "missing" cosmids from bacterial clones received from the Sanger Centre, however injection priority is given to DNA received from the Sequencing Consortium unless a cosmid is of particular interest. We have received cosmid DNA for chromosome II and will be initiating injection of this DNA in the near future.
A complete list of cosmids which are available as transgenic strains is available on the WWW at http://darwin.mbb.sfu.ca/imbb/dbaillie/cosmid.html. Also listed on this site are cosmids for which transgenic strains are currently in the works and an abridged version of the GenBank entries for both sets of cosmids. Strains can be ordered by sending an e-mailed request to djanke@darwin.mbb.sfu.ca.
All transgenic strains created for this project are constructed in a wild-type background. This provides a healthy stock strain which can be use to cross the extrachromosomal arrays into strains with different mutational backgrounds. In this manner these strains can be used to rescue mutations whose approximate physical position is known. It is our hope that the utilization of these strains by the C.elegans community will enhance the rate at which the physical and genetic maps are correlated.
We are currently utilizing these strains to correlate the genetic and physical maps in the central gene cluster of chromosome III, flanked by the genes dpy-17 on the left and emb-9 on the right. In a number of mutagenesis screens, our labs have created a large number of mutations in essential genes contained in this region. We are systematically rescuing these mutations, and have currently positioned the genes let-981 and let-983 to the cosmids F44E2 and ZK643 respectively.

(Click on picture for map expansion)