DNA Sequencing - 3D

DNA sequencing is the process of working out the order of the building blocks or bases in a strand of DNA before we can sequence the DNA it has to be cut up into smaller pieces that are inserted into plasmid DNA and then put into bacterial cells this makes it possible to produce lots and lots of copies of it as the bacterial cells multiply the DNA is then isolated from the bacteria and sent for sequencing the isolated DNA is transferred to a plate where the sequencing reaction will take place a mixture of ingredients is added these include free DNA bases a C G T DNA polymerase enzyme and DNA primers modified DNA bases labeled with colored fluorescent tags are also added these are called Terminator bases to start the sequencing reaction everything is heated to 96 degrees Celsius this separates the DNA into two single strands the temperature is then lowered to 50 degrees this enables the DNA primers to bind to the plasmid DNA a temperature is then increased to 60 degrees and the enzyme DNA polymerase binds to the primer DNA DNA polymerase starts making a new strand of DNA by adding unlabeled DNA bases to the target DNA it continues to add DNA bases until a terminator base is added these Terminator bases have been chemically altered so that no more bases can be added to the new strand of DNA once a Terminator base is added the DNA polymerase enzyme stops making DNA and falls away from the strand everything is then heated to 96 degrees Celsius again to separate the new DNA strand from the original strand this process of heating and cooling is repeated again and again to produce lots of fragments of DNA of different lengths the lengths of each fragment depends on when a terminator base got added you to read the sequence of the DNA the various fragments are separated by length using a process called electrophoresis a capillary tube is lowered into each well of the plate and an electrical charge is applied this causes the negatively charged DNA molecules to move through the capillary tube each capillary contains a porous gel the shorter fragments of DNA moved through the gel more easily than the longer DNA fragments as a result the fragments become arranged by size from the shortest to the longest as the DNA fragments come to the end of the capillary a laser makes the Terminator bases light up the color is detected by a camera and recorded each Terminator base is labeled with a different color a flora sees green sea blue G yellow and T red the shortest DNA fragments will be read first and the longest read last the sequencing machine records the color of the Terminator bases as a series of colored blocks each colored block represents the labeled Terminator base at the end of each fragment of DNA by converting the colors into letters we get the sequence of our piece of DNA

Channel: yourgenome

Views: 564,866

Rating: 4.9385066 out of 5

Keywords: DNA, DNA sequencing, 3D Animation

Id: ONGdehkB8jU

Length: 4min 55sec (295 seconds)

Published: Wed Sep 28 2016