CASTOR1

Chr 22

cytosolic arginine sensor for mTORC1 subunit 1

Also known as: GATSL3

NCBI Gene: 652968ENSG00000239282UniProt: Q8WTX7

Enables several functions, including arginine binding activity; identical protein binding activity; and protein sequestering activity. Involved in cellular response to L-arginine; cellular response to amino acid starvation; and regulation of TORC1 signaling. Located in GATOR2 complex and cytosol. [provided by Alliance of Genome Resources, Jul 2025]

0
ClinVar variants
0
Pathogenic / LP
0.03
pLI score
0
Active trials
Clinical Summary— CASTOR1
⚡
Population Constraint (gnomAD)
Low constraint (pLI 0.03) — loss-of-function variants are relatively tolerated in the population.
Some data sources returned errors (1)

clinvarCount: Error: NCBI fetch failed: 429 https://eutils.ncbi.nlm.nih.gov/entrez/eutils/esearch.fcgi

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

gnomAD
Tolerant — LoF & missense variants common in population
LoF Constraint?LOEUF (Loss-of-function Observed/Expected Upper bound Fraction) is the upper bound of the 90% CI for LoF OE — the preferred gnomAD v4 metric. Lower = more intolerant to LoF. LOEUF < 0.35 = highly constrained.
0.75LOEUF
pLI 0.028
Z-score 2.24
OE 0.35 (0.18–0.75)
Tolerant

Typical tolerance to LoF variation

Missense Constraint?Missense Z-score: standard deviations fewer missense variants observed vs. expected. Z > 3.09 (p < 0.001) = gene does not tolerate missense variation. OE missense < 0.6 is also considered constrained.
1.59Z-score
OE missense 0.69 (0.60–0.79)
140 obs / 203.9 exp
Tolerant

Mild missense constraint

Observed / Expected Ratios?Shaded band = 90% confidence interval. Vertical tick = point estimate. Grey threshold line = gnomAD constraint cutoff for that variant class.
LoF OE?Ratio of observed to expected LoF variants. Upper CI bound (LOEUF) ≤ 0.35 = strong LoF constraint signal.0.35 (0.18–0.75)
0≤0.351.4
Missense OE?Ratio of observed to expected missense variants. OE ≤ 0.6 = fewer missense variants than expected by chance.0.69 (0.60–0.79)
0≤0.61.4
Synonymous OE?Control metric — synonymous variants are largely neutral and expected near OE = 1.0. Significant deviation may indicate annotation issues.0.88
0≤1.21.6
LoF obs/exp: 5 / 14.1Missense obs/exp: 140 / 203.9Syn Z: 0.91

ClinVar Variant Classifications

0 submitted variants in ClinVar

ClinVar

Protein Context — Lollipop Plot

CASTOR1 · protein map & ClinVar variants

Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.

OMIM — Genotype-Phenotype Relationships

1 OMIM entry

OMIM
Clinical Literature
Landmark / reviewRecent case evidence
Key Publications
Landmark & review papers · by relevance
PubMed
Top 10 resultsSearch PubMed ↗
Recent Gene-Specific Literature
Gene in title · MEDLINE · newest first
Europe PMC
Top 5 resultsSearch Europe PMC ↗

Clinical Trials

Active and recruiting trials from ClinicalTrials.gov

ClinicalTrials.gov

No active trials found for this gene.

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External Resources

Links to major genomics databases and tools