BME100 f2015:Group4 1030amL4
BME 100 Fall 2015 | Home People Lab Write-Up 1 | Lab Write-Up 2 | Lab Write-Up 3 Lab Write-Up 4 | Lab Write-Up 5 | Lab Write-Up 6 Course Logistics For Instructors Photos Wiki Editing Help | |||||||||||||||||||||||||||||||||
OUR TEAMLAB 4 WRITE-UPProtocolMaterials
PCR Reaction Sample List
DNA Sample Set-up Procedure
http://learn.genetics.utah.edu/content/labs/pcr/
Research and DevelopmentPCR - The Underlying Technology The Definitions and Functions of the Parts of PCR Reactions PCR provides a useful tool for replicating DNA in a timely and efficient fashion. In this PCR reaction, the template DNA is copied into the new DNA. The primers added to the PCR reaction attach to the end of the DNA segment of interest using base-pairing of DNA; the Taq Polymerase then attaches to the primers at the end of the segments. This Taq Polymerase makes a copy of the DNA segment by assembling nucleotides. Finally, the dNTP's (or deoxyribonucleotides) serve as the foundation of DNA segments, built into certain sequences of the four types of nucleotides: Thymine (T), Adenine (A), Cytosine (C), and Guanine (G). This whole process builds new copies of sequences of DNA. (https://en.wikipedia.org/wiki/Polymerase_chain_reaction) What Occurs During Thermal Cycling During the initial step of PCR, the thermal cycler is heated to 95 degree Celsius for three minutes. Inside the tube, the enzymes added to the solution (Taq Polymerase and primers) are turned on. This step heats the DNA for the next step of denaturization, causing them to start unwinding. In the next step, denaturing occurs when the thermal cycler heats to 95 degree Celsius for thirty seconds. During this short period of time, the double strands of DNA are separated into two strands since the heat causes the hydrogen bonds to break. The third step, annealing, occurs at 57 degree Celsius for thirty seconds; during this period, the introduced primers bind to the strands of DNA before the single strands can recombine at this lower temperature. Two primers attach to the end of each strand, one at the beginning and the other at the end. In the fourth step, extension, the thermal cycler is heated to 72 degree Celsius for thirty seconds. In this step, the Taq Polymerase attaches to the primer and uses base pairing of nucleotides to create a copy of the DNA segment until this enzyme reaches the end of the segment. During the final step of the reaction at 72 degree Celsius for three minutes, the reaction guarantees that every piece of DNA was extended in the previous step. Lastly, the final hold at four degree Celsius stops the PCR reaction by deactivating the Taq Polymerase through lowering the temperature. (https://en.wikipedia.org/wiki/Polymerase_chain_reaction) How the Bases Anneal The base Adenine (A) bonds to Thymine (T). Thymine (T) attaches to the base Adenine (A). Cytosine (C) binds to Guanine (G). The base Guanine (G) attaches to Cytosine (C). (https://en.wikipedia.org/wiki/Polymerase_chain_reaction) The Steps of Thermal Cycling in which Base-Pairing Occurs In thermal cycling of PCR reactions, base-pairing occurs during the steps of annealation and extension. During the step of annealation, the temperature in the thermal cycler drops, prompting the primer to bind to DNA segment of interest. Next, the thermal cycler raises the temperature, causing the Taq Polymerase to attach to the primer. It then uses base pairing on the DNA segment to create a copy of the original DNA. (https://en.wikipedia.org/wiki/Polymerase_chain_reaction)
SNP Information & Primer DesignBackground: About the Disease SNP This specific disease SNP “TGG” affects the production levels of melatonin. A nucleotide substitution from CGG to TGG, causes for the gene MC1R to amplify its function, which is to encode the receptor proteins for melanocyte hormones. These receptor proteins help facilitate the production of melatonin. Due to this amplification, melatonin levels (pheomelanin) increase which affect the phenotype of individuals with this disease-related SNP causing for lighter hair and/or skin color. This affected gene is an essential determinant in human pigmentation.
Primer Design and Testing
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