SOCR 330 Lecture Notes - Eukaryote, Tetrahymena, Telomerase
Document Summary
Places 10 base single-stranded rna primer on dna to be replicated. Primer provides 3"-oh end for dna polymerase to add nucleotides. Addition of dna polymerase iii to primosome forms replisome. Dna pol iii forms phosphodiester bonds adding nucleotides to 3"oh ends of leading strand and okazaki fragments. Lagging strand must loop to place replicating dna section in 5" 3" orientation. Separate pieces of newly synthesized dna formed on lagging strand (discontinuous replication) 200 bp sections of lagging strand loop to position old dna in 5" 3" position so dna polymerase iii can add nucleotide to 3" oh group. Each okazaki fragment has own 10 base rna primer. 10 base gap is filled by dna pol i. Replication of linear eukaryote dna: the telomere problem. Removal of rna primer leaves new dna strands 10 bases shorter at 5" end than old strands. Results in loss of 10 bases from telomeres each time dna replicates.