Leucyl-tRNA synthetase (LeuRS) is an essential RNA splicing factor for yeast mitochondrial introns. Intracellular experiments have suggested that it works in collaboration with a maturase that is encoded within the bI4 intron. RNA deletion mutants of the large bI4 intron were constructed to identify a competently folded intron for biochemical analysis. The minimized bI4 intron was active in RNA splicing and contrasts with previous proposals that the canonical core of the bI4 intron is deficient for catalysis. The activity of the minimized bI4 intron was enhanced in vitro by the presence of the bI4 maturase or LeuRS.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2785312 | PMC |
| http://dx.doi.org/10.1074/jbc.M109.031179 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Two independent activities define Ccm1p as a moonlighting protein in Saccharomyces cerevisiae.
Biosci Rep
December 2012
Department of Biological Sciences, Alcorn State University, Alcorn State, MS 39096-7500, U.S.A.
Ccm1p is a nuclear-encoded PPR (pentatricopeptide repeat) protein that localizes into mitochondria of Saccharomyces cerevisiae. It was first defined as an essential factor to remove the bI4 [COB (cytochrome b) fourth intron)] and aI4 [COX1 (cytochrome c oxidase subunit 1) fourth intron] of pre-mRNAs, along with bI4 maturase, a protein encoded by part of bI4 and preceding exons that removes the intronic RNA sequence that codes for it. Later on, Ccm1p was described as key to maintain the steady-state levels of the mitoribosome small subunit RNA (15S rRNA).
View Article and Find Full Text PDFLeucyl-tRNA synthetase-dependent and -independent activation of a group I intron.
J Biol Chem
September 2009
Department of Biochemistry, University of Illinois, Urbana, Illinois 61801, USA.
Leucyl-tRNA synthetase (LeuRS) is an essential RNA splicing factor for yeast mitochondrial introns. Intracellular experiments have suggested that it works in collaboration with a maturase that is encoded within the bI4 intron. RNA deletion mutants of the large bI4 intron were constructed to identify a competently folded intron for biochemical analysis.
View Article and Find Full Text PDFFunctional divergence of a unique C-terminal domain of leucyl-tRNA synthetase to accommodate its splicing and aminoacylation roles.
J Biol Chem
August 2006
Department of Biochemistry, University of Illinois, Urbana, Illinois 61801-3732, USA.
Leucyl-tRNA synthetase (LeuRS) performs dual essential roles in group I intron RNA splicing as well as protein synthesis within the yeast mitochondria. Deletions of the C terminus differentially impact the two functions of the enzyme in splicing and aminoacylation in vivo. Herein, we determined that a fiveamino acid C-terminal deletion of LeuRS, which does not complement a null strain, can form a ternary complex with the bI4 intron and its maturase splicing partner.
View Article and Find Full Text PDFAn inserted region of leucyl-tRNA synthetase plays a critical role in group I intron splicing.
EMBO J
December 2002
Department of Biology and Biochemistry, University of Houston, Houston, TX 77204-5001, USA.
Yeast mitochondrial leucyl-tRNA synthetase (LeuRS) binds to the bI4 intron and collaborates with the bI4 maturase to aid excision of the group I intron. Deletion analysis isolated the inserted LeuRS CP1 domain as a critical factor in the protein's splicing activity. Protein fragments comprised of just the LeuRS CP1 region rescued complementation of a yeast strain that expressed a splicing-defective LeuRS.
View Article and Find Full Text PDFThe bI4 group I intron binds directly to both its protein splicing partners, a tRNA synthetase and maturase, to facilitate RNA splicing activity.
RNA
December 2000
Department of Biology and Biochemistry, University of Houston, Texas 77204-5513, USA.
The imported mitochondrial leucyl-tRNA synthetase (NAM2p) and a mitochondrial-expressed intron-encoded maturase protein are required for splicing the fourth intron (bI4) of the yeast cob gene, which expresses an electron transfer protein that is essential to respiration. However, the role of the tRNA synthetase, as well as the function of the bI4 maturase, remain unclear. As a first step towards elucidating the mechanistic role of these protein splicing factors in this group I intron splicing reaction, we tested the hypothesis that both leucyl-tRNA synthetase and bI4 maturase interact directly with the bI4 intron.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!