Localization and DNA sequence of a replication origin in the rhodopsin gene locus of Chinese hamster cells.

摘要: A chromosomal origin of DNA replication has been localized within the single-copy rhodopsin gene locus in Chinese hamster (line CHO) cells using two methods. In first method, segments were identified at 3 to 15 kb intervals approximately 75 (kb = 103 bases) cloned genomic containing early-replicating near its middle. The then used as hybridization probes quantify their corresponding synchronized progressed into S phase. second synthesized vivo or permeabilized early phase was hybridized with slot-blots identify earliest replicating part mapped region. method indicates that is located a 10 region beginning 4 upstream from and extending 1 beyond gene. confirms location vicinity very 4.5 itself. An extended 12 encompasses entire sequenced for analysis comparison currently characterized regions associated CHO dihydrofolate reductase (dhfr) human c-myc genes. There are several sequence similarities between dhfr regions, including common transcription promoter consensus sequences, rodent Alu repeats 3′-A + T rich flanking T-rich yeast ARS Drosophila SAR concensus simple (GA)n repeats, but there no direct similarity.