Structure of DNA formed in the first step of CAD gene amplification.

摘要: Abstract Thirty-three independent mutant cell lines were selected in single steps for resistance to low concentrations of N-(phosphonacetyl)-L-aspartate and the structure their amplified DNA was probed, using a set recombinant phage cosmids containing total 380 kb DNA. In all 33 lines, CAD gene at least 65 flanking amplified, an average 2.6-fold. Six other regions co-amplified mutants, but sometimes different extent than CAD. Novel joints, marking recombinations which link each other, found surprisingly rarely. There only three within sequence examined lines. Each novel joint present one copy per cell, line homologous probe. The frequency joints is consistent either with very large single-step possibly 10,000 gene, or strong bias against recombination cloned sequences used as probes. Our previous finding that probes hybridize situ unusually chromosome arms several mutants most first possibility.