mrna lifetime - (Oct/22/2005 )
can u tell me the average lifetime of an mrna in a human cell?
the life span of mRNA is about 2.5 minutes(i read it in 1 of de book) but while searching 4 de lifespan of mRNA in de net(google search) i got de following info:
In prokaryotes (bacteria) the entire lifespan of an mRNA might be over in 5-10 minutes. In eukaryotes (think mammals, or humans) mRNA takes a longer time to be degraded. Most eukaryotic mRNA might take about 5 minutes to be transcribed and about 15-20 minutes for post-transcriptional modifications to be made before leaving the cell. Their half-lives in the cytoplasm range from 4-24 hours. In other words, within 4-24 hours, a certain population of mRNA would have been cut by half.
hope so de info was of some help to u.
PONDER this ... some cells like platelets etc. that do not contain nuclei, have RNA that survives the lifetime of the cell (for platelets ~ 120 days).
The half-life is dependent on the gene where some mRNA's are made and degraded quickly (minutes to hours) while others will stay around for days.
After a mRNA was transcribed all are not going to translation in Eukaryotes. They are mostly 80% digested by RNase inside the nuclei, and the rest come out for translation.
life time may depends upon the need of the product, if the cell need the product it is keep safe by the cell otherwise digested by the nucliase Enzymes.