Gtr1-Gtr2 GTPase complex

GO:1990131 · Other · Multiprotein complex · Proposed

A heterodimer GTPase complex. In S. cerevisiae, this complex contains Gtr1p and Gtr2p proteins. [GO:1990131]

Synonyms: Gtr1p-Gtr2p complex; Rag GTPase heterodimer

UniProt location names: UniProt Consortium, CC BY 4.0. Reference label and route sources.

Components

Component	Type	Part of / acts on	Grounding	Genes	Stoichiometry	Essential	Role
Gtr1 Rag-family GTPase	Protein	part of	Reviewed label only (reviewed name; no accession asserted)	GTR1		UNKNOWN	Rag-family small GTPase subunit that heterodimerizes with Gtr2 in the yeast Gtr1-Gtr2 GTPase complex. `GO:1990131` Gene Ontology cellular-component term for the Gtr1-Gtr2 GTPase complex. `DOI:10.1093/genetics/152.3.853` Nakashima, Noguchi and Nishimoto 1999 identified budding-yeast Gtr2 as a novel Gtr1-interacting protein. `DOI:10.1016/j.bbrc.2005.08.108` Wang et al. 2005 characterized the Saccharomyces cerevisiae Gtr1p-Gtr2p GTPase complex during cell-proliferation regulation.
Gtr2 Rag-family GTPase	Protein	part of	Reviewed label only (reviewed name; no accession asserted)	GTR2		UNKNOWN	Rag-family small GTPase subunit that heterodimerizes with Gtr1 in the yeast Gtr1-Gtr2 GTPase complex. `GO:1990131` Gene Ontology cellular-component term for the Gtr1-Gtr2 GTPase complex. `DOI:10.1093/genetics/152.3.853` Nakashima, Noguchi and Nishimoto 1999 identified budding-yeast Gtr2 as a novel Gtr1-interacting protein. `DOI:10.1016/j.bbrc.2005.08.108` Wang et al. 2005 characterized the Saccharomyces cerevisiae Gtr1p-Gtr2p GTPase complex during cell-proliferation regulation.

Taxonomic distribution

NCBITaxon:4932 Saccharomyces cerevisiae — VARIABLE: Budding yeast is the curated model for the Gtr1/Gtr2 Rag-family heterodimer that regulates TORC1 at the vacuole-associated EGO complex. [GO:1990131]

Canonical examples

NCBITaxon:4932 Saccharomyces cerevisiae — Yeast model in which Gtr1 and Gtr2 form the Rag-family GTPase heterodimer associated with EGOC and TORC1 control. [GO:1990131]

Functions

TORC1 signaling GO:0038202 — The budding-yeast Gtr1-Gtr2 heterodimer links amino acid state to TORC1 activity and localization with the vacuolar EGO anchor complex.
- GO:0038202 Gene Ontology biological-process term for TORC1 signaling.
- DOI:10.4161/cc.26000 Panchaud, Peli-Gulli and De Virgilio 2013 described Gtr1-Gtr2 as the yeast Rag GTPase heterodimer that associates with Ego1 and Ego3 in EGOC for amino acid activation of TORC1.
- DOI:10.1091/mbc.E15-07-0470 Kira et al. 2016 followed the dynamic relocation of the TORC1-Gtr1/2-Ego1/2/3 complex between the yeast vacuolar membrane and punctate sites.

Mechanism graphs

Gtr1-Gtr2 supports yeast TORC1 signaling (REGULATION)

In Saccharomyces cerevisiae, Gtr1 and Gtr2 form a Rag-family GTPase heterodimer that localizes with the EGO anchor on the vacuolar membrane and regulates TORC1 signaling.

Subject	Predicate	Object	Evidence
Gtr1 Rag-family GTPase	is part of	Gtr1-Gtr2 GTPase complex	`GO:1990131` Gene Ontology cellular-component term for the Gtr1-Gtr2 GTPase complex. `DOI:10.1093/genetics/152.3.853` Nakashima, Noguchi and Nishimoto 1999 identified budding-yeast Gtr2 as a novel Gtr1-interacting protein. `DOI:10.1016/j.bbrc.2005.08.108` Wang et al. 2005 characterized the Saccharomyces cerevisiae Gtr1p-Gtr2p GTPase complex during cell-proliferation regulation.
Gtr2 Rag-family GTPase	is part of	Gtr1-Gtr2 GTPase complex	`GO:1990131` Gene Ontology cellular-component term for the Gtr1-Gtr2 GTPase complex. `DOI:10.1093/genetics/152.3.853` Nakashima, Noguchi and Nishimoto 1999 identified budding-yeast Gtr2 as a novel Gtr1-interacting protein. `DOI:10.1016/j.bbrc.2005.08.108` Wang et al. 2005 characterized the Saccharomyces cerevisiae Gtr1p-Gtr2p GTPase complex during cell-proliferation regulation.
Gtr1-Gtr2 GTPase complex	localizes to	fungal-type vacuole membrane	`DOI:10.1091/mbc.E15-07-0470` Kira et al. 2016 followed the dynamic relocation of the TORC1-Gtr1/2-Ego1/2/3 complex between the yeast vacuolar membrane and punctate sites.
Gtr1-Gtr2 GTPase complex	regulates	TORC1 signaling	`GO:0038202` Gene Ontology biological-process term for TORC1 signaling. `DOI:10.4161/cc.26000` Panchaud, Peli-Gulli and De Virgilio 2013 described Gtr1-Gtr2 as the yeast Rag GTPase heterodimer that associates with Ego1 and Ego3 in EGOC for amino acid activation of TORC1. `DOI:10.1091/mbc.E15-07-0470` Kira et al. 2016 followed the dynamic relocation of the TORC1-Gtr1/2-Ego1/2/3 complex between the yeast vacuolar membrane and punctate sites.

Discussions

CURATION_TODO (OPEN): Resolve exact source-neutral InterPro, Pfam, or NCBIfam groundings for the two yeast Gtr1-Gtr2 Rag-family GTPase subunit classes. This first Gtr1-Gtr2 record names the yeast Gtr1 and Gtr2 constituent subunits but leaves family grounding unset until exact orthology and RagA/B versus RagC/D paralogy boundaries are reviewed per subunit.
CURATION_TODO (RESOLVED): Keep Ego1, Ego2 and Ego3 Ragulator/EGO anchor subunits outside this Gtr1-Gtr2 heterodimer record. GO:1990131 denotes the Gtr1-Gtr2 heterodimer itself, while GO:0071986 denotes the vacuolar EGO/Ragulator anchor for Rag GTPases; Tafur et al. 2026 separated Gtr1 and Gtr2 from the Ego1, Ego2 and Ego3 anchor subunits within the pentameric EGOC.
CURATION_TODO (RESOLVED): Keep GATOR/SEAC regulator subcomplexes outside this Gtr1-Gtr2 heterodimer record. GATOR1/SEACIT and GATOR2/SEACAT are distinct SEA/GATOR regulator branches upstream of the Gtr1-Gtr2 Rag-family target and are represented by GO as complexes separate from GO:1990131.
CURATION_TODO (RESOLVED): Keep the Lst4-Lst7 GAP complex outside this Gtr1-Gtr2 heterodimer record. Lst4-Lst7 acts on the Rag-family GTPase Gtr2 as an upstream GAP regulator, whereas GO:1990131 denotes the Gtr1-Gtr2 heterodimer itself.

Evidence

GO:1990131 Gene Ontology cellular-component term for the Gtr1-Gtr2 GTPase complex.
GO:0032991 Gene Ontology cellular-component parent term for protein-containing complexes.
GO:0038202 Gene Ontology biological-process term for TORC1 signaling.
DOI:10.1093/genetics/152.3.853 Nakashima, Noguchi and Nishimoto 1999 identified budding-yeast Gtr2 as a novel Gtr1-interacting protein.
DOI:10.1016/j.bbrc.2005.08.108 Wang et al. 2005 characterized the Saccharomyces cerevisiae Gtr1p-Gtr2p GTPase complex during cell-proliferation regulation.
DOI:10.4161/cc.26000 Panchaud, Peli-Gulli and De Virgilio 2013 described Gtr1-Gtr2 as the yeast Rag GTPase heterodimer that associates with Ego1 and Ego3 in EGOC for amino acid activation of TORC1.
DOI:10.1091/mbc.E15-07-0470 Kira et al. 2016 followed the dynamic relocation of the TORC1-Gtr1/2-Ego1/2/3 complex between the yeast vacuolar membrane and punctate sites.
DOI:10.1016/j.celrep.2015.08.059 Peli-Gulli et al. 2015 identified Lst4-Lst7 as a GTPase-activating protein complex for the yeast Rag-family GTPase Gtr2.
DOI:10.1038/s41594-026-01746-2 Tafur et al. 2026 determined the yeast SEAC-EGOC supercomplex and separated the Gtr1/Gtr2 heterodimer from the Ego1/Ego2/Ego3 anchor within EGOC.

Curation history

2026-09-18T10:19:15Z codex · CREATED_RECORD — Scaffolded by scripts/new_record.py
2026-09-18T10:20:16Z codex · EXPANDED_RECORD — Added Gtr1-Gtr2 synonymy, protein-complex parentage, reviewed-label-only yeast Gtr1/Gtr2 Rag-family components, Saccharomyces scope, a TORC1 signaling function, GO/DOI evidence, a nonmechanistic TORC1-regulation graph, and subunit-grounding plus EGO/Ragulator and GATOR/SEAC boundary discussions.
2026-09-18T10:20:38Z codex · REFORMATTED_RECORD — Expanded shared YAML evidence aliases into plain repeated mappings.
2026-09-18T10:40:17Z codex · ADDRESSED_PR_REVIEW — #1142: Added a resolved Lst4-Lst7 GAP boundary discussion and Cell Reports evidence so the graph's omitted GAP cycles are explicitly out of scope.

Source: data/structures/other/gtr1_gtr2_gtpase_complex.yaml