TY - JOUR
T1 - Yeast mitochondrial leucyl-tRNA synthetase CP1 domain has functionally diverged to accommodate RNA splicing at expense of hydrolytic editing
AU - Sarkar, Jaya
AU - Poruri, Kiranmai
AU - Boniecki, Michal T.
AU - McTavish, Katherine K.
AU - Martinis, Susan A.
PY - 2012/4/27
Y1 - 2012/4/27
N2 - The yeast mitochondrial leucyl-tRNA synthetase (ymLeuRS) performs dual essential roles in group I intron splicing and protein synthesis. A specific LeuRS domain called CP1 is responsible for clearing noncognate amino acids that are misactivated during aminoacylation. The ymLeuRS CP1 domain also plays a critical role in splicing. Herein, the ymLeuRS CP1 domain was isolated from the full-length enzyme and was active in RNA splicing in vitro. Unlike its Escherichia coli LeuRS CP1 domain counterpart, it failed to significantly hydrolyze misaminoacylated tRNALeu. In addition and in stark contrast to the yeast domain, the editing-active E. coli LeuRS CP1 domain failed to recapitulate the splicing activity of the full-length E. coli enzyme. Although LeuRS-dependent splicing activity is rooted in an ancient adaptation for its aminoacylation activity, these results suggest that the ymLeuRS has functionally diverged to confer a robust splicing activity. This adaptation could have come at some expense to the protein's housekeeping role in aminoacylation and editing.
AB - The yeast mitochondrial leucyl-tRNA synthetase (ymLeuRS) performs dual essential roles in group I intron splicing and protein synthesis. A specific LeuRS domain called CP1 is responsible for clearing noncognate amino acids that are misactivated during aminoacylation. The ymLeuRS CP1 domain also plays a critical role in splicing. Herein, the ymLeuRS CP1 domain was isolated from the full-length enzyme and was active in RNA splicing in vitro. Unlike its Escherichia coli LeuRS CP1 domain counterpart, it failed to significantly hydrolyze misaminoacylated tRNALeu. In addition and in stark contrast to the yeast domain, the editing-active E. coli LeuRS CP1 domain failed to recapitulate the splicing activity of the full-length E. coli enzyme. Although LeuRS-dependent splicing activity is rooted in an ancient adaptation for its aminoacylation activity, these results suggest that the ymLeuRS has functionally diverged to confer a robust splicing activity. This adaptation could have come at some expense to the protein's housekeeping role in aminoacylation and editing.
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U2 - 10.1074/jbc.M111.322412
DO - 10.1074/jbc.M111.322412
M3 - Article
C2 - 22383526
AN - SCOPUS:84860379061
SN - 0021-9258
VL - 287
SP - 14772
EP - 14781
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 18
ER -