ISSN:
1432-0886
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Abstract We have used nascent strand determination analysis to map start sites of DNA replication in the mouse ribosomal gene cluster in which individual copies of the ribosomal genes are separated by intergenic spacer regions. One origin of bidirectional replication (OBR) was localized within a 3 kb region centered about 1.6 kb apstream of the rDNA transcription start site. At least one additional initiation site is situated near the 3′ end of the transcription unit. Adjacent to the OBR at the transcription start site are located two amplification-promoting sequences, i.e., APS1 and APS2. Nuclease-hypersensitive sites were identified in both the two APSs as well as in the OBR region, thus indicating that these sequences have an altered chromatin structure. In the OBR an intrinsically bent region, a purine-rich element and other prospective initiation zone components are found.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00352115
