Difference between PCDNA and Brdu - (Dec/03/2008 )

Hey guys,

Just a question. What are the differences between PcDNA and BrdU? Both used to stain synthesising DNA.
Thanks

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BrdU - is synthetic nucleoside, which when added to the cells, gets incorporated into the newly synthesized DNA in the place of Thymidine (T), and hence marker of replicating cells/DNA. You can then do immunolocalization of BrdU.

PCNA (Proliferating Cell Nuclear Antigen) (not PcDNA - that is a plasmid) - is an endogenous protein largely expressed during S phase of cell cycle and hence marker of replicating cells/DNA. You do immunolocalization of PCNA.

The main differences in my view are..

--BrdU can give you sharper snap-shots - you control the when to add, how much to add, and when to stop by fixing the cells. Which can be a matter of minutes or hours. You can not control endogenous PCNA protein expression in that way.

--BrdU treatment and localization is a prospective experiment. You plan ahead, treat the cells, and look for prolifetaring cells.

--PCNA localization can be done retrospectively. Any fixed cells/tissues from a dozen year old collection can still be investigated.

and there are a dozen small things that come to mind, but not worth the time typing them, nor easy to express precisely.

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