TY - JOUR
T1 - Requirements for self-splicing of a group I intron from Physarum polycephalum
AU - Rocheleau, Gail Auger
AU - Woodson, Sarah A.
N1 - Funding Information:
We wish to especially thank V.Vogt for the gift of plasmids and for helpful advice. This work was supported by the NIH (GM46686) and by an American Cancer Society Junior Faculty Research Award (S.W.). S.W. also wishes to acknowledge the Pew Scholars Program in the Biomedical Sciences.
PY - 1994/10/11
Y1 - 1994/10/11
N2 - The third intron from Physarum polycephalum (Pp LSU 3) is one of the closest known relatives to the wellstudied Tetrahymena group I intron. Both introns are located at the same position in the 26S rRNA gene, and with the exception of an open reading frame in Pp LSU 3, are highly homologous. While Pp LSU 3 has been shown to self splice, little is known about its activity in vitro. We have examined the requirements for self splicing in greater detail. Despite its similarity to the Tetrahymena intron, Pp LSU 3 is 1500-fold less reactive, demonstrates a preference for high salt, and exhibits a low Km for GTP. Removal of the open reading frame results in a modest increase of activity. This system provides an opportunity to understand how sequence variations in two related introns alter the efficiency of autoexcision, and how this relates to adaptation of group I introns to their particular sequence context.
AB - The third intron from Physarum polycephalum (Pp LSU 3) is one of the closest known relatives to the wellstudied Tetrahymena group I intron. Both introns are located at the same position in the 26S rRNA gene, and with the exception of an open reading frame in Pp LSU 3, are highly homologous. While Pp LSU 3 has been shown to self splice, little is known about its activity in vitro. We have examined the requirements for self splicing in greater detail. Despite its similarity to the Tetrahymena intron, Pp LSU 3 is 1500-fold less reactive, demonstrates a preference for high salt, and exhibits a low Km for GTP. Removal of the open reading frame results in a modest increase of activity. This system provides an opportunity to understand how sequence variations in two related introns alter the efficiency of autoexcision, and how this relates to adaptation of group I introns to their particular sequence context.
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U2 - 10.1093/nar/22.20.4315
DO - 10.1093/nar/22.20.4315
M3 - Article
C2 - 7937160
AN - SCOPUS:0027942148
SN - 0305-1048
VL - 22
SP - 4315
EP - 4320
JO - Nucleic acids research
JF - Nucleic acids research
IS - 20
ER -