Consensus transcription factor binding sites - how are the bases denoted (Jan/24/2006 )

I am analysing TF binding sites

In a 1997 paper the consensus
GDRRADYCCC and
In a 2004 paper the following consensus
GGGRNNYYCC

is said to be the consensus for NF kappa beta

I want to know
1) Why these consensus are different.. I am thinking maybe because it changed as new findings were published..am I right?
2) What do each of those letters mean ?
like D, R, N,Y

please let me know of these if you know

thanks

d = ?

N = any base

Y = pyrimidine

R = purine

I think that NF-kB changes with time and there are many subunits involved; perhaps a given consensus alters with new findings, but I think there is some flexibility as well

is there a website where I can analyse my sequence for NF-kappa-B sites based on this consensus or is that something to be done manually

www.genomatix.de

use matinspector

it will give them all to you if you are patient, with probabilities too...and this part is free. with a little elbow grease you can get some very good potential sites with only the free stuff.

I used it prior to designing some emsa oligos

You might also try the San Diego Supercomputer

http://workbench.sdsc.edu

This has lots of extremely useful nucleic acid analysis tools and a very speedy sequence search function

TFSearch is also a useful web based search for transcription factors for your DNA sequence of interest.
Ceri