where does the process of dna replication begin
DNA replication For a cell to divide, it must first replicate its DNA.[11] This process is initiated at particular points in the DNA, known as "origins", which are targeted by initiator proteins.[4] In E. coli this protein is DnaA; in yeast, this is the origin recognition complex.[12] Sequences used by initiator proteins tend to be "AT-rich" (rich in adenine and thymine bases), because A-T base pairs have two hydrogen bonds (rather than the three formed in a C-G pair) and thus are easier to strand-separate.[13] Once the origin has been located, these initiators recruit other proteins and form the pre-replication complex, which unwinds the double-stranded DNA.
S phase S phase (synthesis phase) is the part of the cell cycle in which DNA is replicated, occurring between G1 phase and G2 phase. Precise and accurate DNA replication is necessary to prevent genetic abnormalities which often lead to cell death or disease. Due to the importance, the regulatory pathways that govern this event in eukaryotes are highly conserved. This conservation makes the study of S-phase in model organisms such as Xenopus laevis embryos and budding yeast relevant to higher organisms.