ISSN:
1432-0983
Keywords:
Ribosomal DNA
;
Small subunit
;
18s
;
Degenerate introns
;
Ascomycetes
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract Insertions of less than 100 nt occurring in highly conserved regions of the small subunit ribosomal DNA (SSU rDNA) may represent degenerate forms of the group-I introns observed at the same positions in other organisms. A 63-nt insertion at SSU rDNA position 1512 (relative to theEscherichia coli SSU rDNA) of the lichen-forming fungusArthonia lapidicola can be folded into a secondary structure with two stem loops and a pairing of the insertion and flanking sequences. The two stem loops may correspond to the P1 and P2, and the insertion-flanking pairing to the P10, of a group-I intron. Considering these small insertions as degenerate introns provides important clues to the evolution and catalytic function of group-I introns.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF02426963
