sos response การใช้

• Transcription of the SOS response genes is negatively regulated by the LexA repressor.
• He and Evelyn M . Witkin set basis for the discovery of SOS response.
• This induces the SOS response, an emergency repair process that is also error-prone, thereby generating mutations.
• They are expressed under stress conditions such as cold shock, iron depletion, onset of the SOS response and sugar stress.
• The SOS response hypothesis was put forward by Radman in 1970 in an unpublished letter sent to various researchers which was published in 1974.
• Simply put, the SOS response in " E . coli " is a response to DNA damage that must be repaired.
• The activity of PRR enzymes is regulated by the SOS response in bacteria and may be controlled by the postreplication checkpoint response in eukaryotes.
• Weigle also demonstrated the inducible nature of DNA damage-response genes in bacteria, a phenomenon that has come to be known as the SOS response.
• This could account for a decrease in ATP concentration in cells following triggering of the SOS response, causing slowing of cellular processes and inhibited cell growth.
• In connection with the damage inducible ( din ) genes recA, lexA and umuD, the umuC gene is essentially involved in bacterial mutagenesis through the SOS response.
• This suicidal production mechanism would appear to be very costly, except for the fact that it is regulated by the SOS response, which responds to significant DNA damage.
• The key point to understand here is that LexA and RecA both were required for adaptive mutation to occur, and without the SOS response adaptive mutation would not be possible.
• Thus the first SOS repair mechanism to be induced is nucleotide excision repair ( NER ), whose aim is to fix DNA damage without commitment to a full-fledged SOS response.
• As the SOS response is a general response to genotoxic lesions, one strain of S . typhimurium with the appropriate reporter gene construct is sufficient to identify all classes of bacterial genotoxins.
• The SOS / umu assay test evaluates the ability of a substance to induce DNA damage; it is based on the alterations in the induction of the SOS response due to DNA damage.
• On the other hand, RecG mutants were key to the expression of RecA-dependent mutations, which were a major portion of study in the SOS response experiments, such as the ability to utilize lactose.
• Changes in presence of one or the other was shown to affect the SOS response, which in turn affected how the cells were able to process lactose, which should not be confused with the lactose starvation experiment.
• Bacteriophage 186 is often compared to the more extensively studied lambda phage as both their prophages respond to DNA damage in the host, more commonly known as the SOS response, even though the two bacteriophages are evolutionarily distinct.
• For example, in bacteria, a regulatory network aimed at repairing DNA damages ( called the SOS response in " Escherichia coli " ) has been found in many bacterial species . " E . coli"
• In addition, polyamine participate in initiating the expression of SOS response of Colicin E7 operon and down-regulate proteins that are essential for colicin E7 uptake, thus conferring a survival advantage on colicin-producing " E . coli " under stress conditions.