biochemistry6-DNAstructureandreplication解释.ppt

DNA Replication: synthesis of daughter DNA from parental DNA Transcription: synthesis of RNA using DNA as the template Translation: protein synthesis using mRNA molecules as the template Reverse transcription: synthesis of DNA using RNA as the template Know the structure of DNA and chromosome in prokaryotic and eukaryotic. Know the process of DNA replication in prokaryotic and eukaryotic. F1 DNA structure F2 Chromosomes （染色体） F3 DNA replication in bacteria DNA在细菌中的复制 F4 DNA replication in eukaryotes DNA在真核细胞中的复制 Section 1DNA structure Primary Structure － Double helix of DNA Right-handed double helix Antiparallel. 10 base pairs or 3.4nm per turn Complementary base pairing: A and T; G and C Section 2Chromosomes（染色体） A reaction in which daughter DNAs are synthesized using the parental DNAs as the template. Transferring the genetic information to the descendant generation with a high fidelity Template: double stranded DNA Substrate: dNTP Primer: short RNA fragment with a free 3′-OH end Enzyme: DNA-dependent DNA polymerase (DDDP), other enzymes, protein factor Section 3DNA replication in bacteria DNA在细菌中的复制 The first DNA- dependent DNA polymerase (short for DNA-pol I) was discovered in 1958 by Arthur Kornberg who received Nobel Prize in physiology or medicine in 1959. Later, DNA-pol II and DNA-pol III were identified in experiments using mutated E.coli cell line. All of them possess the following biological activity. 1. 5??3? polymerizing 2. exonuclease Bidirectional replication Semi-continuous Replication Primase Helicase Topoisomerase(拓扑异构酶) Section 4DNA replication in eukaryotes DNA在真核细胞中的复制 DNA replication is closely related with cell cycle. Multiple origins on one chromosome, and replications are activated in a sequential order rather than simultaneously. Replication of eukaryotes 真核生物多个复制起始点、复制子与复制叉 The terminal structure of eukaryotic DNA of chromosomes is called telomere. Te