Distance on DNA between specific replication sites in exit from midblastula and the beginning of transcription

Range 150 - 300 kb
Organism African clawed frog Xenopus laevis
Reference Conti C, Saccà B, Herrick J, Lalou C, Pommier Y, Bensimon A. Replication fork velocities at adjacent replication origins are coordinately modified during DNA replication in human cells. Mol Biol Cell. 2007 Aug18(8):3059-67. p.3059 right column 2nd paragraphPubMed ID17522385
Primary Source Hyrien, O., Maric, C., and Mechali, M. (1995). Transition in specification of embryonic metazoan DNA replication origins. Science 270, 994–997.PubMed ID7481806
Comments "In early Xenopus embryos, transcription is repressed and DNA replication starts at nonspecific sites every 5–15 kb. The exit from midblastula and the beginning of transcription reorganizes the spatio-temporal pattern of origin firing, with replication occurring at specific sites every 150 –300 kb (primary source). In spite of this flexibility in the distribution of active origins along the genome, the total number of origins is a crucial parameter for the efficient duplication of the genome (Machida et al., 2005 Shechter and Gautier, 2005)."
Entered by Uri M
ID 111193