Are introns just junk?

[arlin at ac.dal.ca]

In article <CFDGHs.Jzq at usenet.ucs.indiana.edu>, John Logsdon <jlogsdon at bio.indiana.edu> writes:
> 
> In article <2ablph$afl at gazette.bcm.tmc.edu> Arthur Kania,
> ak990140 at SPECIALK.IAIMS.BCM.TMC.EDU also writes:
>>There is probably lots of other stuff that I didn't mention; you should
> read some
>>chapters from Molecular Cell Biology (Darnell, Lodish and Baltimore) or
> another
>>basic cell bio textbook.
> 
> Well, don't take too much faith in what the major texts tell you since
> they are highly biased (i.e.: Darnell was one of the early architects of
> IE). 

Here, here!  Its been known for about 10 years that there is not a general
1:1 correspondence between exons and domains (see Blake, 1983, Nature 306:
p. 535), but this canard is repeated _ad nauseam_ in reviews and textbooks, 
such as Watson, et al. (_Molecular Biology of the Gene_) which has the 
sententious section heading "Exons Correspond to Functional Domains of 
Proteins" (p. 1146).  This textbook also informs us of "The Great 
Antiquity of mRNA Introns" (p. 1145) and that "Protein-coding Genes 
were Assembled by Exon Shuffling" (p. 1146), as though these were 
matters of established fact, which they emphatically are not.

>      Also, (donning my jeweled turbin) I predict many of these
> evolutionary conclusions about introns will be changed in the coming
> years.
> 
> John

Gosh, John, is this prediction based on some top-secret discovery by Team
Palmer, or did it come to you in a vision?  Please fill us in!

Arlin

Dr. Arlin Stoltzfus
Department of Biochemistry
Dalhousie University
Halifax, Nova Scotia
B3H 4H7 CANADA
internet: arlin at ac.dal.ca