Construction of chromosome jumping and linking libraries in E. coli

Chromosome jumping allows the use of one point on a chromosome as a starting point for exploring another potentially distant point on the same chromosome without cloning the intervening sequences as in chromosome walking. A linking library consists of genomic fragments that each contain a particular restriction site with a marker inserted into it. Because the sequences flanking the marker represent the termini of two contiguous genomic restriction fragments, the linking clones can be used, in conjunction with a specific jumping library made with the same restriction enzyme, to expedite jumping between consecutive restriction fragments. Separate protocols present strategies for constructing general and specific jumping libraries from total genomic DNA. An additional protocol details construction of a linking library from flow-sorted chromosomes. Support protocols provide instructions for preparing genomic insert DNA, supF gene fragments, and Chromosome jumping allows the use of one point on a chromosome as a starting point for exploring another potentially distant.