Note that this locus is complex: it appears to produce several proteins with no sequence overlap.
Expression: According to AceView, this gene is expressed at very high level, 7.5 times the average gene in this release. The sequence of this gene is defined by 2441 GenBank accessions, some from brain (seen 89 times), thymus (41), testis (37), uterus (32), lung (31), eye (25), spleen (25) and 161 other tissues. We annotate structural defects or features in 11 cDNA clones.
Alternative mRNA variants and regulation: The gene contains 46 distinct introns (43 gt-ag, 3 gc-ag). Transcription produces 37 different mRNAs, 34 alternatively spliced variants and 3 unspliced forms. There are 4 probable alternative promotors, 10 non overlapping alternative last exons and 6 validated alternative polyadenylation sites (see the diagram). The mRNAs appear to differ by truncation of the 5' end, truncation of the 3' end, presence or absence of 16 cassette exons, overlapping exons with different boundaries, splicing versus retention of 13 introns. 175 bp of this gene are antisense to spliced gene kababo, raising the possibility of regulated alternate expression.
5 variants were isolated in vivo, despite the fact that they are predicted targets of nonsense mediated mRNA decay (NMD).
Efficacy of translation may be reduced by the presence of a shorter translated product (uORF) initiating at an AUG upstream of the main open reading frame (in variant fAug10, gAug10, nAug10).
Function: There are 17 articles specifically referring to this gene in PubMed. Functionally, the gene has been proposed to participate in pathways (Aminoacyl-tRNA biosynthesis, Metabolic pathways) and a process (glutaminyl-tRNA aminoacylation). Proteins are expected to have molecular functions (glutamine-tRNA ligase activity, protein binding, ATP binding, nucleotide binding) and to localize in various compartments (cytosol, mitochondrial matrix, cytoplasm, extracellular space, membrane). Putative protein interactors have been described (AIMP2, ASLANDCRCP, BAT2, CPNE3, DUSP11, MAP3K5, RNF11, SMAD9, TRAF2).
Protein coding potential: 27 spliced mRNAs putatively encode good proteins, altogether 29 different isoforms (20 complete, 1 COOH complete, 8 partial), some containing domains tRNA synthetases class I (E and Q), catalytic domain, tRNA synthetases class I (E and Q), anti-codon binding domain, Glutaminyl-tRNA synthetase, non-specific RNA binding region part 1, Glutaminyl-tRNA synthetase, non-specific RNA binding region part 2 [Pfam], some transmembrane domains, a N-myristoylation domain, a peroxisomal domain, a coiled coil stretch [Psort2]; 1 of the 20 complete proteins appears to be secreted. The remaining 10 mRNA variants (7 spliced, 3 unspliced; 6 partial) appear not to encode good proteins.
Isoform QARS.qAug10 is annotated using as Met a Kozak-compatible a..ACG. start, thereby gaining 150 amino acids N-terminal to the first AUG. Finally proteins from this gene may be modulated by acetylation; phosphorylation; ubiquitination, as detailed at PhosphoSite.

Please quote: AceView: a comprehensive cDNA-supported gene and transcripts annotation, Genome Biology 2006, 7(Suppl 1):S12

Alternative mRNAs are shown aligned from 5' to 3' on a virtual genome where introns have been shrunk to a minimal length. Exon size is proportional to length, intron height reflects the number of cDNAs supporting each intron, the small numbers show the support of the introns in deep sequencing (with details in mouse-over) . Introns of the same color are identical, of different colors are different. 'Good proteins' are pink, partial or not-good proteins are yellow, uORFs are green. 5' cap or3' poly A flags show completeness of the transcript.
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