Radioactive Probes

Radioactive Probes - under a microscope. Autoradiography is...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
Radioactive Probes The blue-white screening method described above selects for bacteria that have any gene. Radioactive probes can be used to find colonies that have specific genes. Probes are short, single-stranded segments of DNA whose base sequence matches part of the gene in question. It is not necessary to match the entire gene, just a small fragment. The cells are lysed and the DNA is denatured by treating it with an alkaline solution. When the probe is mixed with the denatured DNA, it will form a double-helix in the area where the gene has complimentary bases. If the probe is radioactive or fluorescent, it can be visualized. The gene can then be isolated or cloned as needed. It may be possible to see the chromosome and the location on the chromosome while viewing
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: under a microscope. Autoradiography is a process in which film is used to show the area of the vector where the probe has attached. This area is the gene in question. Obtaining Probes Probes can be synthesized using a DNA synthesis machine. This requires a knowledge of at least a part of the sequence of the nucleotides in the gene to be probed so that a complimentary fragment can be created. If this is unknown, it may be deduced by knowing the sequence of amino acids in the protein that the gene codes. Amino acids often have more than one spelling, so it may be necessary to create several different alternative probes. In some cases, a similar gene which has already been isolated from another organism can serve as a probe....
View Full Document

This note was uploaded on 01/04/2012 for the course BSC BSC1005 taught by Professor Orlando,rebecca during the Fall '10 term at Broward College.

Ask a homework question - tutors are online