BCHM 3050 1st Edition Lecture 20 Outline of Last Lecture I Steps in DNA Synthesis a Initiation b Elongation c Termination II Structure of DNA Polymerase Dimer III Dimeric Function of DNA Polymerase IV Overview of the E coli Replisome V Termination of DNA Replication in Prokaryotes VI Ends of DNA are not completely replicated VII Telomere Structure and Function Outline of Current Lecture I Telomerase Function II Polymerase Chain Reaction PCR III The CR in PCR Current Lecture I Telomerase Function a Telomeres recruit telomerase enzyme and telomerase brings in an RNA template in with it so that the DNA polymerase can fill in the rest of the nucleotides b Telomerase is a reverse transcriptase because it can synthesis its own RNA c Telomerase provides the RNA primer and 3 OH group for polymerase to fill in the gaps at the end d Telomere repeats are only in the parent strand e Telomerase extends the 3 end of the parents strand first then uses the telomere as a template to fill in the top strand These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute II III Polymerase Chain Reaction PCR a 1980 Dr Kary Mullis decided to replicate DNA in test tube PCR b Make more than a billion in just 30 minutes c Heat the DNA at 90 95 degrees C for 1 3 min to break the DNA strands apart Denaturation d This replaces the role of Helicase without any origins etc e Primers bind to 3 ends of separated strands f He added 2 primers dNTPs dATP dGTP dCTP dTTP buffer DNA polymerase Taq template DNA in test tube g Had to decrease the temperature to allow the primers to join Annealing 4050 degrees C h Extension 70 degrees C for about 5 min i Denaturation mirrored Helicase j Annealing mirrored RNA primase ssBP DNA polymerase III k Extension mirrored DNA polymerase III The CR in PCR a Exponential amplification 2n b Primers always stick to 3 end of parent strand c Primers are usually 20 30 nucleotides long d Possible exam questions What would be the primers for this DNA sequence watch out for orientation of 5 to 3
View Full Document
Unlocking...