SIN/MEN signaling complex

GO:0160065 · Cytoskeleton · Multiprotein complex · Proposed

A protein complex associated with the mitotic spindle pole body during interphase and mitosis and comprises of the proteins of the septation initiation signaling network (SIN) of fission yeast or mitotic exit network (MEN) of budding yeast, organized by two scaffold/adaptor proteins. [GO:0160065]

Synonyms: SIN/MEN signalling complex; MEN signaling complex; SIN signaling complex

Part of: outer plaque of mitotic spindle pole body (GO:0061499)

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

Taxonomic distribution

• NCBITaxon:4896 Schizosaccharomyces pombe — COMMON: Fission yeast is the model organism for the septation initiation network branch of this SPB-associated complex; no broader fungal distribution is asserted here. [DOI:10.1038/emboj.2010.317]
• NCBITaxon:4932 Saccharomyces cerevisiae — COMMON: Budding yeast is the model organism for the mitotic exit network branch of this SPB-associated complex; no broader fungal distribution is asserted here. [DOI:10.1016/j.semcdb.2012.04.001]

Canonical examples

• NCBITaxon:4896 Schizosaccharomyces pombe — Reference fission-yeast system for SIN proteins organized at the spindle pole body by scaffold and adaptor proteins. [DOI:10.1038/emboj.2010.317]
• NCBITaxon:4932 Saccharomyces cerevisiae — Reference budding-yeast system for the MEN branch of the yeast mitotic-exit signaling network. [DOI:10.1016/j.semcdb.2012.04.001]

Functions

• SIN/MEN mitotic-exit signaling — The SPB-associated SIN/MEN signaling complex organizes septation-initiation and mitotic-exit signaling proteins in fission and budding yeast.
  • GO:0160065 GO:0160065 defines a mitotic-SPB-associated complex composed of septation initiation network or mitotic exit network proteins.
  • DOI:10.1016/j.semcdb.2012.04.001 Hergovich and Hemmings 2012 reviewed yeast SIN and MEN pathways as Hippo-related signaling pathways that control mitotic exit and cytokinesis.

Discussions

• INTERPRETATION (RESOLVED): Keep GO:0160065 broad enough for both yeast SIN and MEN branches and distinct from narrower SIN or GAP subcomplexes. GO:0160065 denotes the SPB-associated SIN/MEN signaling complex. GO:0160066 and GO:0160067 are narrower SIN-only subclasses for the old-SPB interphase complex and the new-SPB anaphase complex, respectively, while GO:1990334 denotes the two-component GAP complex that regulates Tem1/Spg1 rather than the whole SIN/MEN complex.
• CURATION_TODO (OPEN): Resolve exact source-neutral family groundings for SIN/MEN scaffold, adaptor, kinase, and GTPase-cycle proteins. This first GO-backed record captures the SPB-associated SIN/MEN complex without treating lineage-specific protein names as conserved component families or guessing InterPro, Pfam, NCBIfam, UniProtKB, or Complex Portal groundings.

Evidence

• GO:0160065 Gene Ontology cellular-component term for the SIN/MEN signaling complex, with the British spelling as an exact synonym and SIN and MEN signaling complex names as narrow synonyms.
• GO:0032991 Gene Ontology parent term for protein-containing complex.
• GO:0061499 Gene Ontology cellular-component term for the outer plaque of the mitotic spindle pole body, which contains the SIN/MEN signaling complex by parthood.
• DOI:10.1038/emboj.2010.317 Johnson and Gould 2011 studied regulation of fission-yeast SIN scaffold Sid4 and Plo1 kinase localization at spindle pole bodies.
• DOI:10.1016/j.semcdb.2012.04.001 Hergovich and Hemmings 2012 reviewed Hippo signaling in the G2/M cell-cycle phase, including lessons from the yeast MEN and SIN pathways.
• DOI:10.1038/ncb2514 Grallert et al. 2012 showed that Sid2 activates Fin1 to regulate mitotic commitment in S. pombe. SIN-ablation experiments and localization of untagged Sid2 support a cytoplasmic G2 population operating outside the SIN context, not evidence that the whole SPB-associated SIN complex controls this G2 function.

Curation history

• 2026-09-29T18:41:40Z codex · CREATED_RECORD — Scaffolded by scripts/new_record.py
• 2026-09-29T18:44:38Z codex · EXPANDED_RECORD — Added GO synonyms, protein-complex parentage, mitotic outer-plaque parthood, fission- and budding-yeast scope, a SIN/MEN mitotic-exit signaling function, GO and literature evidence, and boundary/component discussions.
• 2026-10-11T16:16:38Z codex · ADDRESS_SAVED_REVIEW — Addressed #2224: Corrected the Grallert 2012 evidence note to distinguish cytoplasmic G2 Sid2-Fin1 activity outside the SIN from the whole SPB-associated SIN complex; retained all other biological claims.

Source: data/structures/cytoskeleton/sin_men_signaling_complex.yaml