Abstract
Pulse labelled rDNA from cultured somatic cells of Xenopus laevis was examined by electron microscope autoradiography. The pattern of replication closely resembles that of bulk chromosomal DNA and differs considerably from rDNA synthesis during amplification in the oocyte. - About 0.15% of the rDNA molecules in the purified preparations were circular. The presence of interlocked circles of equal size indicates that the circles are not in vitro cyclization artefacts, but may represent free rRNA genes. A low frequency of circles was also seen in Xenopus blood rDNA. Their stability in high concentration of formamide suggests that they too did not arise after DNA extraction.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
