G2/M interpretation
TONKINSON JOHN L (TONKINSON_JOHN_L@LILLY.COM)
Mon, 12 May 1997 15:44:58 +0000 (GMT)
To those of you on the cell cycle board, I apologize for the redundancy,
but I wanted some more input.
We have been analyzing the cell cycle of 2 cell lines, a parent and a
daughter stably transfected with a gene of interest. The transfectant has
a significantly reduced doubling time compared to vector control. The
most striking difference in DNA histograms is a fairly dramatic reduction
in the percentage of G2/M cells in the transfectant (this is confirmed by
integration with WinCycle - 0 order S phase and aggregate correction).
There is a concomitant increase in G1 and S phase percentages. We feel
that this indicates a decreased transit time across G2/M. Is this a
correct assesment? We tried BrdU labeling to get an accurate picture, but
both cell lines have very long doubling times (even the transfectant) and
we were unable to get enough BrdU incorporated to visualize (We tried
several times). Does our interpretation sound logical? Is there anything
else we can or should do? We tried synchronization with aphidicolin but
the cells did not progress through s and G2/M tightly enough to give
conclusive data.
Any comments or suggestions would be appreciated along with alternative
hypothesis.
Thanks
John Tonkinson
Lilly Research Labs
JTonk@lilly.com