MT-TK

Summary

MT-TK (mitochondrially encoded tRNA-Lys (AAA/G), HGNC:7489) is a mitochondrial tRNA gene on chromosome mitochondria.

At a glance

• Gene type: non-coding (Mt_tRNA) — no protein product; not a drug target. Variant/disease associations are omitted (they would be positional, from an overlapping protein-coding gene).

Identifiers

Gene identifiers

Field	Value
HGNC ID	HGNC:7489
Approved symbol	MT-TK
Name	mitochondrially encoded tRNA-Lys (AAA/G)
Location	mitochondria
Locus type	RNA, transfer
Status	Approved
Aliases	trnK
Ensembl gene	ENSG00000210156
Ensembl biotype	Mt_tRNA
OMIM	590060
Entrez	4566
RNAcentral	URS000007A90A — tRNA, 70 nt, 6 organism(s)

Gene structure

Transcript identifiers

Ensembl transcripts: 1 — 1 Mt_tRNA

ENST00000387421

RefSeq mRNA: 0 — MANE Select: None

Canonical transcript exons

ENST00000387421 — 1 exons

Exon	Start	End
ENSE00001544484	8295	8364

Expression profiles

Bgee: expression breadth ubiquitous, 118 present calls, max score 99.68.

Top tissues by expression

118 total, by Bgee expression score (0-100, higher = more expressed):

Tissue	Anatomy ID	Expression score	Quality
sural nerve	UBERON:0015488	99.68	gold quality
skeletal muscle tissue	UBERON:0001134	99.28	gold quality
caudate nucleus	UBERON:0001873	99.23	gold quality
putamen	UBERON:0001874	99.23	gold quality
substantia nigra	UBERON:0002038	99.10	gold quality
apex of heart	UBERON:0002098	99.07	gold quality
amygdala	UBERON:0001876	99.04	gold quality
granulocyte	CL:0000094	98.97	gold quality
nucleus accumbens	UBERON:0001882	98.97	gold quality
Ammon’s horn	UBERON:0001954	98.95	gold quality
right frontal lobe	UBERON:0002810	98.82	gold quality
frontal cortex	UBERON:0001870	98.76	gold quality
hypothalamus	UBERON:0001898	98.68	gold quality
C1 segment of cervical spinal cord	UBERON:0006469	98.46	gold quality
anterior cingulate cortex	UBERON:0009835	98.35	gold quality
heart left ventricle	UBERON:0002084	97.67	gold quality
prefrontal cortex	UBERON:0000451	97.61	gold quality
cerebral cortex	UBERON:0000956	97.36	gold quality
right adrenal gland cortex	UBERON:0035827	97.05	gold quality
right hemisphere of cerebellum	UBERON:0014890	97.01	gold quality
vermiform appendix	UBERON:0001154	96.59	gold quality
adult mammalian kidney	UBERON:0000082	96.40	gold quality
cerebellar hemisphere	UBERON:0002245	96.19	gold quality
right adrenal gland	UBERON:0001233	95.88	gold quality
brain	UBERON:0000955	95.85	gold quality
leukocyte	CL:0000738	95.43	gold quality
muscle of leg	UBERON:0001383	95.43	gold quality
monocyte	CL:0000576	95.31	gold quality
gastrocnemius	UBERON:0001388	95.29	gold quality
left adrenal gland	UBERON:0001234	95.24	gold quality

Single-cell (SCXA)

Detected in 1 experiment(s), a significant marker in 0.

Experiment	Marker?	Max mean expression
E-ANND-3	no	0.00

Regulation

Is transcription factor: no

Literature-anchored findings (GeneRIF, showing 12)

• We identified a novel heteroplasmic mutation (8300T > C) in the tRNAlys gene (MTTK) from a patient with unexplained exercise intolerance. (PMID:16810691)
• a family carrying the classic MTTK mutation with a variable degree of heteroplasmy, presenting in childhood as isolated recurrent muscle pain as the first symptom of the disease (PMID:17293137)
• A 8328G>A tRNALys mutation was detected in a 59 year old man with myopathy and exercise intolerance. (PMID:17410322)
• We describe a A8344G tRNALys mutation associated with recurrent brain stem stroke-like episodes in a 17 year-old girl. (PMID:19253012)
• We describe a typical MERRF (A8344G) mutation of the mitochondrial DNA associated with depressive mood disorders. (PMID:19266142)
• we describe the clinical and molecular features of a new large multigenerational family with the G8363A mtDNA tRNA(Lys) gene mutation and we review the literature of cases with this mutation (PMID:19278689)
• This is the first reported case of a double-point mutation in mtDNA, tRNA(Lys) and tRNA(Leu) genes, both of which were heteroplasmic and pathogenic for MERRF/MELAS overlap syndrome. (PMID:20610441)
• The results unambiguously demonstrate that modifications pre-structure the anticodon as a key prerequisite for efficient and accurate recognition of cognate and wobble codons by transfer RNA lysine. (PMID:22227389)
• study of a Greek family that includes seven symptomatic cases of 8344 A>G lys mitochondrial tRNA mutation; clustering of unusual manifestations in this kindred suggests that much of the phenotypic variability of 8344 A>G is determined by mitochondrially encoded modifiers in cis (PMID:22681518)
• provides evidence toward the pathogenicity of the m.8348A>G mutation and suggest that m.5628T>C is probably a neutral polymorphism. (PMID:22743145)
• Study further broadens the clinical spectrum of the m.8344A>G mutation, document the large clinical variability between carriers of the same mutation, even within families and indicate an overlap of the phenotype with other mitochondrial DNA-associated syndromes (PMID:26995359)
• A Novel MTTK Gene Variant m.8315A>C as a Cause of MERRF Syndrome. (PMID:35886028)

Cross-species orthologs

0 orthologs

Protein

Non-coding RNA — no protein product; not a drug target.

Function

No curated pathway, Gene-Ontology, or interaction data.

Disease & clinical

No curated disease, variant, or cancer-driver associations.

Drugs & pharmacology

No drug or pharmacology data — not an established drug target.