[BioC] How to load annotation package dynamically?

[Chanchal Kumar]

Dear Bioconductor Developers and Users,
   
  I have created few annotation packages which are for organism specific
proteomics database from IPI(http://www.ebi.ac.uk/IPI/IPIhelp.html) .
Now I am keen on writing a generic utility function for GO enrichment
using "GOStats". The input to the function would be 1) the test list of
IPI ids, 2) The universe set and 3) the Annotation package to be used.

I can see from the Affymetrix microarray analysis modules that given a
CEL file for any platform the function (say mas5(), or gcrma()) loads
the appropriate package dynamically and the user doesn't have to worry
about specifying the platform the data belongs to. Also the probes etc
are matched automatically. I want to do something similar so that the
user doesn't have to worry about mapping the IPIs to the Entrez ids etc.
I should mention that the packages I created have mappings to ENTREZ and
GO etc.

I am aware that this is an abstract request but hope I have explained my
problem in quite some detail. I will be thankful if you could suggest an
elegant way to replicate that functionality. I am kind of lost in all
the code. Any insights will be very helpful.

Thanks in advance!

Best Regards,
Chanchal 
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Chanchal Kumar, Ph.D. Candidate
Dept. of Proteomics and Signal Transduction
Max Planck Institute of Biochemistry
Am Klopferspitz 18
82152 D-Martinsried (near Munich)
Germany
e-mail: chanchal at biochem.mpg.de
Phone: (Office) +49 (0) 89 8578 2296
Fax:(Office) +49 (0) 89 8578 2219
http://www.biochem.mpg.de/mann/
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