identifier: METPO:1000680
label: ring shaped
definition: A cell shape in which an organism forms circular or toroidal structures.
definition_source: DOI:10.1146/annurev-cellbio-101011-155745
trait_category: MORPHOLOGY
term_kind: CLASS
mapping_status: REVIEWED
parent_traits:
- METPO:1000666
synonyms:
- synonym_text: ring
  synonym_type: RELATED_SYNONYM
  source: metpo.owl
- synonym_text: ring-shaped
  synonym_type: RELATED_SYNONYM
  source: metpo.owl
evidence:
- reference: DOI:10.1146/annurev-cellbio-101011-155745
  snippet: cell curvature
  notes: Cell-shape review supports curvature-generating wall patterning as the basis
    for closed-ring morphology.
causal_graphs:
- graph_id: ring_shaped_curved_growth_closure
  title: Ring-shape curved growth and pole closure
  description: DOI-backed graph linking strongly curved peptidoglycan growth and pole-to-pole
    closure to toroidal ring morphology.
  nodes:
  - node_id: ring_shaped_trait
    label: ring shaped
    node_type: TRAIT
    grounding: METPO:1000680
    description: Closed circular or toroidal cell geometry.
  - node_id: curved_pg_growth
    label: strongly curved peptidoglycan growth
    node_type: BIOLOGICAL_PROCESS
    description: Asymmetric lateral wall synthesis producing high cell curvature.
  - node_id: pole_to_pole_closure
    label: pole-to-pole closure
    node_type: BIOLOGICAL_PROCESS
    description: Connection or near-contact of the two cell poles producing a ring.
  - node_id: toroidal_geometry
    label: toroidal geometry
    node_type: BIOLOGICAL_PROCESS
    description: Closed ring-like cell-body geometry.
  - node_id: mreb_filaments
    label: MreB filaments
    node_type: GENE_OR_PROTEIN
    description: Actin-like cytoskeletal filaments guiding cell-wall synthesis.
  - node_id: cell_wall_growth_rate
    label: rate of cell wall growth
    node_type: BIOLOGICAL_PROCESS
    description: Rate of peptidoglycan cell-wall synthesis during growth.
  - node_id: pg_insertion_perpendicular
    label: peptidoglycan insertion perpendicular to long axis
    node_type: BIOLOGICAL_PROCESS
    description: Circumferential peptidoglycan insertion oriented perpendicular to
      the cell long axis.
  - node_id: bactofilin_polymers
    label: bactofilin polymers
    node_type: GENE_OR_PROTEIN
    description: Cytoskeletal bactofilin polymers that localize to sites of wall remodeling.
  - node_id: cell_wall_biosynthesis
    label: cell wall biosynthesis
    node_type: BIOLOGICAL_PROCESS
    description: Spatially regulated synthesis of the peptidoglycan cell wall.
  - node_id: bactofilin_lmdc_module
    label: bactofilin-M23 peptidase module
    node_type: GENE_OR_PROTEIN
    description: Conserved bactofilin and M23 peptidase functional module remodeling
      the wall locally.
  - node_id: wall_biosynthesis_mode_change
    label: local change in cell wall biosynthesis mode
    node_type: BIOLOGICAL_PROCESS
    description: Local shift in the mode of cell-wall synthesis producing shape changes.
  - node_id: crva_polymer
    label: CrvA polymer
    node_type: GENE_OR_PROTEIN
    description: Periplasmic CrvA polymer that skews peptidoglycan synthesis to generate
      curvature.
  - node_id: pg_synthesis_rate_skew
    label: skewed peptidoglycan synthesis rates
    node_type: BIOLOGICAL_PROCESS
    description: Asymmetric peptidoglycan synthesis rates across the cell body.
  - node_id: crescentin
    label: crescentin
    node_type: GENE_OR_PROTEIN
    description: Intermediate filament-like protein promoting cell curvature.
    grounding: UniProtKB:A0A2N9AY16
  - node_id: cell_curvature
    label: cell curvature
    node_type: QUALITY
    description: Degree of curvature of the cell body.
  edges:
  - subject: curved_pg_growth
    predicate: produces
    object: pole_to_pole_closure
    description: Strong axial curvature brings the poles into proximity.
    evidence:
    - reference: DOI:10.1146/annurev-cellbio-101011-155745
      snippet: cell curvature
      notes: Supports curvature-generating wall growth as a producer of closed ring
        forms.
    predicate_id: METPO:2000202
  - subject: pole_to_pole_closure
    predicate: causes
    object: toroidal_geometry
    description: Pole-to-pole closure yields a toroidal body.
    evidence:
    - reference: DOI:10.1146/annurev-cellbio-101011-155745
      snippet: cell shape is genetically determined
      notes: Supports closed ring forms as genetically determined shape outcomes.
    predicate_id: biolink:causes
  - subject: toroidal_geometry
    predicate: manifests as
    object: ring_shaped_trait
    description: Toroidal geometry manifests the ring-shaped trait.
    evidence:
    - reference: DOI:10.1146/annurev-cellbio-101011-155745
      snippet: cell curvature
      notes: Supports the trait endpoint via curvature-driven closure.
    predicate_id: METPO:2007400
  - subject: mreb_filaments
    predicate: correlates with
    object: cell_wall_growth_rate
    description: MreB filament motion correlates with the rate of cell-wall growth.
    evidence:
    - reference: DOI:10.3390/microorganisms12071309
      notes: the motion of MreB filaments correlates with the rate of cell wall growth;
        general shape-control edge.
  - subject: mreb_filaments
    predicate: guides
    object: pg_insertion_perpendicular
    description: MreB double filaments guide peptidoglycan insertion perpendicular
      to the long axis.
    evidence:
    - reference: DOI:10.1038/s41467-024-49785-x
      notes: These cytoskeletal structures guide peptidoglycan insertion perpendicular
        to the long axis of the cell.
  - subject: bactofilin_polymers
    predicate: spatially regulates
    object: cell_wall_biosynthesis
    description: Bactofilin polymers spatially regulate cell-wall biosynthesis.
    evidence:
    - reference: DOI:10.7554/eLife.86577.2
      notes: bactofilin polymers... indicating a central role in the spatial regulation
        of cell wall biosynthesis.
  - subject: bactofilin_lmdc_module
    predicate: promotes
    object: wall_biosynthesis_mode_change
    description: Conserved bactofilin and M23 peptidase module promotes local changes
      in cell-wall biosynthesis mode.
    evidence:
    - reference: DOI:10.7554/eLife.86577.2
      notes: bactofilins and M23 peptidases form a conserved functional module that
        promotes local changes in the mode of cell wall biosynthesis; cross-taxon.
    predicate_id: RO:0002213
  - subject: crva_polymer
    predicate: skews
    object: pg_synthesis_rate_skew
    description: CrvA polymer formation skews peptidoglycan synthesis rates to generate
      curvature.
    evidence:
    - reference: DOI:10.1038/s41467-024-45196-0
      notes: CrvA in Vibrio cholerae... skews peptidoglycan synthesis rates; curvature-generating
        wall patterning.
  - subject: crescentin
    predicate: promotes
    object: cell_curvature
    description: Crescentin promotes cell curvature.
    evidence:
    - reference: DOI:10.1038/s41467-024-45196-0
      notes: the intermediate filament-like protein crescentin in C. crescentus generates
        curvature; canonical curvature determinant.
    predicate_id: RO:0002213
curation_history:
- timestamp: '2026-05-05T01:35:46.892873+00:00'
  curator: seed_from_metpo
  action: SEEDED_FROM_METPO
  changes: imported from data/raw/metpo.owl (CLASS)
  llm_assisted: false
- timestamp: '2026-05-11T22:45:00-07:00'
  curator: claude
  action: CURATED_CAUSAL_GRAPH
  changes: Added DOI-backed causal graph linking strongly curved peptidoglycan growth
    and pole-to-pole closure to ring-shaped morphology.
  llm_assisted: true
- timestamp: '2026-05-20T03:35:31Z'
  curator: claude
  action: GROUND_CAUSAL_PREDICATES
  changes: Grounded 1 causal-edge predicate_id field(s) via mappings/predicate_grounding.tsv
    (METPO:2000202×1).
  llm_assisted: true
- timestamp: '2026-05-23T21:30:07Z'
  curator: claude
  action: GROUND_CAUSAL_PREDICATES
  changes: Grounded 1 causal-edge predicate_id field(s) via mappings/predicate_grounding.tsv
    (METPO:2007400×1).
  llm_assisted: true
- timestamp: '2026-05-24T04:13:19Z'
  curator: claude
  action: RENAME_PREDICATE_LABELS
  changes: 'Renamed 1 causal-edge predicate label(s) to align with existing groundings:
    shapes → causes ×1.'
  llm_assisted: true
- timestamp: '2026-05-24T04:13:22Z'
  curator: claude
  action: GROUND_CAUSAL_PREDICATES
  changes: Grounded 1 causal-edge predicate_id field(s) via mappings/predicate_grounding.tsv
    (biolink:causes×1).
  llm_assisted: true
- timestamp: '2026-06-23T00:00:00Z'
  curator: claude
  action: ENRICH_CAUSAL_GRAPH
  changes: Added 6 evidence-backed generic edges (11 new nodes) from the deep-research
    report.
  llm_assisted: true
- timestamp: '2026-06-24T17:21:13Z'
  curator: claude
  action: GROUND_CAUSAL_PREDICATES
  changes: Grounded 2 causal-edge predicate_id field(s) via mappings/predicate_grounding.tsv
    (RO:0002213×2).
  llm_assisted: true
- timestamp: '2026-06-24T17:21:19Z'
  curator: claude
  action: GROUND_CAUSAL_NODES
  changes: Grounded 1 causal-node grounding field(s) via mappings/node_grounding.tsv
    (UniProtKB:A0A2N9AY16×1).
  llm_assisted: true