DARS2 is the nuclear-encoded mitochondrial aspartate-tRNA ligase. It activates aspartate with ATP and transfers it to mitochondrial tRNA(Asp), supporting synthesis of mitochondrially encoded respiratory-chain proteins. The enzyme forms a homodimer and contains an N-terminal mitochondrial targeting sequence.
Mitochondrial aspartate-tRNA synthetase must accommodate structurally unusual mitochondrial tRNA(Asp); the 2013 structure compares that accommodation with bacterial AspRS. Cross-aminoacylation of bacterial and mitochondrial tRNA(Asp) is a taxonomic/substrate-structure breadth claim, whereas acceptance of tRNA(Asn) is a different aminoacylation-specificity claim. The human GOA includes the latter, so the original experiments matter. The inspected 2013 full text did not settle that point and the 2005 characterization is abstract-only in the cache. Retaining uncertainty is appropriate. Matrix localization is the primary placement, but additional membrane-associated or extracellular activities cannot be dismissed just from that default.
From PMID:15779907(https://pubmed.ncbi.nlm.nih.gov/15779907/):
Both belong to the expected class of synthetases, have a dimeric organization, and aminoacylate Escherichia coli tRNAs as well as in vitro transcribed human mitochondrial tRNAs.
The exact target is A0A9L0SB67, not an arbitrary horse record with a matching name. The reproducible paired-sequence analysis records identity, coverage and internal gaps. It supports homology but is not a reciprocal orthology test. Molecular properties are transferred only with the relevant domain, targeting and paralog constraints. The prediction-time sequence is not independently verified.
The following annotation scopes need source-specific follow-up: aspartate-tRNA(Asn) ligase activity, mitochondrial membrane, obsolete mitochondrial asparaginyl-tRNA aminoacylation, protein binding. Experimental annotations are not removed merely because a cached abstract omits the gene or a specific assay. High-throughput protein-binding rows require their actual partner or complex context before replacement with an informative molecular function.
Research provenance: external Falcon/Edison was attempted with Perplexity fallback. Some requests returned HTTP 429 and fallback returned insufficient-quota HTTP 401; successful external reports are preserved separately. Primary-source manual synthesis is explicitly labeled manual where no external report was available.