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Chung Li Shu

Publications and source records attributed to Chung Li Shu.

2 recordsLinked to original sources

BAC clones generated from sheared DNA.

BAC libraries generated from restriction-digested genomic DNA display representational bias and lack some sequences. To facilitate completion of genome projects, procedures have been developed to create BACs from DNA physically sheared to create fragments extending up to 200 kb. The DNA fragments were repaired to create blunt ends and ligated to a new BAC vector. This approach has been tested by generating BAC libraries from Drosophila DNA with insert lengths between 50 and 150 kb. The libraries lack chimeric clone problems as determined by mapping paired BAC-end sequences to the assembled fly genome sequence. The utility of "sheared" libraries was demonstrated by closure of a previous clone gap and by isolation of clones from telomeric regions, which were notably absent from previous Drosophila BAC libraries.

Animals↗

BAC resources for the rat genome project.

Two 11-fold redundant bacterial artificial chromosome (BAC) libraries (RPCI-32 and CHORI-230) have been constructed to support the rat genome project. The first library was constructed using a male Brown Norway (BN/SsNHsd) rat as a DNA source long before plans for rat genome sequencing had been launched. The second library was prepared from a highly inbred female (BN/SsNHsd/MCW) rat in support of the rat genome sequencing project. The use of an inbred rat strain is essential to avoid problems with genome assembly resulting from the difficulty of distinguishing haplotype variation from variation among duplicons. We have demonstrated the suitability of the library by using a detailed quality assessment of large insert sizes, narrow size distribution, consistent redundancy for many markers, and long-range continuity of BAC contig maps. The widespread use of the two libraries as an integral part of the rat genome project has led to the database annotations for many clones, providing rat researchers with a rich resource of BAC clones that can be screened in silico for genes of interest.

Animals↗