"Sylva Donaldson" <sylva at scar.utoronto.ca> wrote in message
news:Pine.GSO.4.10.10003151109540.2003-100000 at banks.scar...
> Greetings,
>> I've been trying to resolve >8 Mb fragments of restriction digested plant
> chromosomes on pulse-field gels with no success. I've been using a 0.8%
> gel (chromosomal grade agarose), and a CHEF III apparatus, using the
> optimum protocol for S. pombe chromosomes. I've been struggling with
> inconsistent DNA yield, and whether or not I digest the DNA, I get a smear
> at 3 Mb, with no hint of higher molecular weight DNA on the gel. I was
> wondering if anyone has any experience with this. I've toyed with the
> idea that maybe the DNA is shearing as the gel runs, due to the force of
> electorphoresis. Other than that, I'm stumped. I would appreciate any
> help. Please email me directly: sylva at scar.utoronto.ca>>> Sylva Donaldson
Hi
Some one in my lab said look at :
Genomics 52, p1-8, 1998.
Osoegawa et al An Improved approach for construction of BAC libraries.
They don't go as big as 8 megs but it may help.
NB They use a CHEF kit too.
HTH
Choona
