Hyb conditions

[Warren Gallin]

In Article <9406072041.AA13925 at acs2.acs.ucalgary.ca>,
llintott at ACS.UCALGARY.CA ("Lauri Lintott") wrote:
>Dear Logand
>I am not sure if I missed your point but when I hybridize DNA
>probes to Northerns I never use formamide in the hyb buffer.  It
>is not necessary to use formamide unless you are using an RNA
>probe so why bother
>with it?
>
>Lauri
>BioSci
>U of Calgary

So how do you get the stringency up?  Formamide acts to lower the melting
temperature of the duplex.  I do Northerns at 55C with 50% formamide and get
good clean bands.  Without the formamide I would have thought that there
would have been a lot of non-specific hybridization.  Or are you talking
about short oligonucleotide probes?

Warren Gallin,
Department of Zoology, University of Alberta
wgallin at gpu.srv.ualberta.ca