Spliceosomal introns

Those interested in possible functions for at least some junk
and those interested in alternative splicing will probably
find much of interest here. Available free online with
registration. I, unfortunately, haven't read it yet, since
Nature has apparently recently changed their cookie policy to
one that I don't like.

http://www.nature.com/nrg/journal/v7/n3/abs/nrg1807.html

Review
Nature Reviews Genetics 7, 211-221 (March 2006)

The evolution of spliceosomal introns: patterns, puzzles and progress
Scott William Roy and Walter Gilbert

Abstract: The origins and importance of spliceosomal introns
comprise one of the longest-abiding mysteries of molecular
evolution. Considerable debate remains over several aspects
of the evolution of spliceosomal introns, including the timing
of intron origin and proliferation, the mechanisms by which
introns are lost and gained, and the forces that have shaped
intron evolution. Recent important progress has been made in
each of these areas. Patterns of intron-position correspondence
between widely diverged eukaryotic species have provided insights
into the origins of the vast differences in intron number
between eukaryotic species, and studies of specific cases of
intron loss and gain have led to progress in understanding the
underlying molecular mechanisms and the forces that control
intron evolution.


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