An elongation factor-associating domain is inserted into human cysteinyl-tRNA synthetase by alternative splicing.
The amino acid sequence of human cytoplasmic cysteinyl-tRNA synthetase (CRS) was examined by analyzing sequences of genomic and expressed sequence tag fragments. From theses analyses, a few interesting possibilities were suggested for the structure of human CRS. First, different isoforms of CRS may result from alternative splicing. Second, the largest one would comprise 831 amino acids. Third, a new exon was identified encoding an 83 amino acid domain that is homologous to parts of elongation factor-1 subunits as well as other proteins involved in protein synthesis. Northern blot analysis showed three different mRNAs for CRS (of approximately 3.0, 2.7 and 2.0 kb) from human testis while only the 2.7 kb mRNA was commonly detected in other tissues. Expression of the exon 2-containing transcript in testis was confirmed by RT-PCR and northern blotting. CRS containing the exon 2-encoded peptide retained catalytic activity comparable to that lacking this peptide. This peptide was responsible for the specific interaction of CRS with elongation factor-1gamma.
Kim
J E
JE
National Creative Research Initiatives Center for ARS Network, Sung Kyun Kwan University, 300 Chunchun-Dong, Changan-Ku, Suwon-Si, Kyunggi-Do 440-746, Korea.
Kim
K H
KH
Lee
S W
SW
Seol
W
W
Shiba
K
K
Kim
S
S
D000215:Acylation; D017398:Alternative Splicing; D000595:Amino Acid Sequence; D000604:Amino Acyl-tRNA Synthetases / Q000737:chemistry / Q000235:genetics*; D001665:Binding Sites; D015152:Blotting, Northern; D005091:Exons; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D020648:Peptide Elongation Factor 1 / Q000737:chemistry; D010445:Peptide Elongation Factors / Q000737:chemistry*; D012333:RNA, Messenger / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016415:Sequence Alignment; D013737:Testis / Q000201:enzymology
D020648:Peptide Elongation Factor 1; D010445:Peptide Elongation Factors; D012333:RNA, Messenger; D000604:Amino Acyl-tRNA Synthetases; C019975:cysteinyl-tRNA synthetase