DNA fragment

Shao-Yu Chen syc at MED.UNC.EDU
Thu Feb 2 10:29:19 EST 1995


     We have tried to assay DNA fragment from kidney using following protocol:

     1. Tissue homogenate was lysed with hypotonic lysing
buffer(10mMTris,1 mMEDTA) containing 0.2% Triton X-100 for 20 min.
     2. The lysates were centrifuged at 13,000XG for 10min to separeate
intact from fragmented chromatin .
     3. Both pellet and supernatant were precipitated overnight at 4C in
12.5% trichloroacetic acid. The precipitates were sedimented at 13,000 XG
for 4min.
     4. The DNA in the precipitates was hydrolyzed by heating to 90C for
10min in 5% trichloroacetic acid and was quantitated by the diphenylamine
method. 
     However , the DNA in the precipitates can not be hydrolyed by heating
to 90C(or boiling ) in 5% trichloroacetic acid.

     Can anyone out there give me some advice? Thank you in advance.


                                  Shaoyu Chen
                                  UNC- CH
                                  syc at med.unc.edu 



More information about the Methods mailing list