[R--gR] R data structure for network graphs?

[Paul Shannon]

Hello all,

I am brand new to this list; forgive me if I mis-step!

I am relatively new, also, to R, which I am using  in
conjunction with an open source java network visualization
tool, cytoscape (see http://www.cytoscape.org).  We have
lots of whole-genome,high throughput biological data -- microarray, ICAT,
MPSS -- and R (of course!) is very useful in exploring these
data.

I wonder:  has this group defined an R data structure for
representing network graphs, with nodes and edges (and
perhaps with node and edge attributes as well)?  I wish
to include this view of our data along side our experimental
data.

Thank you,

  - Paul Shannon
    Institute for Systems Biology
    Seattle