Because of DNA strand polarity, the bidirectional replication results in two distinct products, “leading” and “lagging” strands, according to the moving direction of the replication fork. The leading strand is synthesized as a single continuous chain, whereas the lagging strand is initia...
一、由单链断裂导致的复制叉坍塌(replication fork collapse)或由DNA复制受阻导致的复制叉断裂(replication fork breakage)是造成DSB的重要原因(复制叉坍塌或断裂几乎在E.coli的每个细胞周期中都会自然发生。在静止期E.coli中,复制叉可以R环为基础组建,并可在基因组中常见的自发单链断裂处坍塌。)。单链断裂可由单链...
The replication fork is created by a helicase, typically forming a hexameric ring, that translocates in the 5′—3′ direction on the template for the lagging strand. The helicase is connected to two DNA polymerase catalytic subunits, each of which is associated with a sliding clamp. Core ...
The space between both DNA helices is not large enough to accommodate a pair of purine bases, and it is too wide to house two pyrimidine bases. The space between both DNA strands is adequate to exactly accommodate a purine-pyrimidine pair. The bases are maintained and held together by ...
The coordinated action of multiple replicative helicase loading factors is needed for the licensing of replication origins prior to DNA replication. Binding of the Origin Recognition Complex (ORC) to DNA initiates the ATP-dependent recruitment of Cdc6, C
The mechanism of DNA synthesis has been inferred from static structures, but the absence of temporal information raises longstanding questions about the order of events in one of life’s most central processes. Here we follow the reaction pathway of a re
Two prokaryotic defence systems, prokaryotic Argonautes (pAgos) and CRISPR–Cas, detect and cleave invader nucleic acids using complementary guides and the nuclease activities of pAgo or Cas proteins. However, not all pAgos are active nucleases. A large
(synthesis)phase.Thetwodaughter.Thetwodaughter DNAmoleculesformedfromreplicationeventuallyDNAmoleculesformedfromreplicationeventually becomechromosomesintheirownrightinthedaughterbecomechromosomesintheirownrightinthedaughter cells.cells. Aswithallphenomenathatinvolvenucleicacids,theAswithallphenomenathatinvolvenucleicacids,...
it can exist in two structural forms that are mirror images of each other but are not superimposable (enantiomers). Just like your left and right hands are mirror images of each other, the two DNA structures are left-handed and right-handed double helices. The DNA double helix is chiral,...
Amino acid substitution analyses of the DNA contact region, two amphipathic alpha-helices and a recognition-helix-like helix outside the dimeric beta-barrel of Epstein-Barr virus nuclear antigen 1. Intervirology 44:271-282.Fujita, T., Ikeda, M., Kusano, S., Yamazaki, M., Ito, S., ...