RNA half life - (May/10/2006 )
hi
can any one tell me why Plant RNA's half life is longer than animal RNA? Is it right or not?
in fact im not sur about it but I exteract genomic DNA from cows and wheat. without using RNase on agarose gel there were no RNA for animal cells but I could see RNA for plant cell.
thanx
Mike.
errr well not intented to offense you, but i assume it's may be becaus the extraction without RNA was better done.
thank you anyway Im going to repeat it
hello again
i repeat that experiment one more time
with some plant and animals again I recieve the same answer
in attached picture from right :1st wel is control - 7 wel for animal Genomic DNA and the rest are plant DNA , no RNase used but you cannot see any RNA for animal Samples,
how did you extract that samples?... 
each wel is for one plant or animal the spices are not the same and the protocol was general Standard Sambrooks for plant / animals
ok so i assume it's sthg based on a phenol chloroform extraction
So i guess the extraction procedure holds sthg wrong (i mean not in the protocol, but maybe in your reagents and / or pipettes and other material) well maybe, I forgot to wrote we use isoamyl chloroform instead of phenol chloroform.
thanx
well how did you get rid of proteins?
phenol allow that, an the step with chloroform helps removing the remaining phenol of the aqueous phase. Chloroform only can't separate all proteins. so you keep quite surely some proteases.
well maybe it is strange but in my lab they believe phenol is very dangerous but we use EtBr easily
even without gloves 
instead of phenol
well we add chloroform/isoamyl alcohol (24:1)
centrifuge @ 14000 rpm for 15 min
transfer supernatant to new sterile tube
repeat this stage for 2 or 3 times
then add 2/3 volume isopropanol and invert the tube
and an after resuspend the pllet in TE buffer
repeat one time cjloroform/isoamyl (24:1)
well it is work here
have fun.