Affinage · Toxoplasma gondii

ILP1

IMC localizing protein ILP1 · UniProt A0A125YKB4

Annotated
2026-09-11
12 papers in source corpus 3 papers cited in narrative 3 extracted findings

Mechanistic narrative

Synthesis pass · prose summary of the discoveries below

ILP1 is a cytoskeletal protein of the inner membrane complex (IMC) in Toxoplasma gondii that contributes to the architecture of the subpellicular network (SPN) underlying the parasite pellicle (PMID:31584943). Its C-terminal coiled-coil domain directly binds the alveolin proteins IMC3 and IMC6 (and IMC27), with distinct regions of the coiled-coil crosslinking to IMC3 versus IMC6, and the IMC3 C-terminal domain and IMC6 N-terminal domain being required for binding (PMID:31584943); ILP1 engages IMC6 through multiple binding interfaces within its alveolin domain, part of the network of alveolin-domain interactions that mediate SPN filament formation (PMID:39264987). Beyond these interactions, no further mechanistic detail on ILP1 has been characterized in the available corpus.

Mechanistic history

Synthesis pass · year-by-year structured walk · 2 steps
  1. 2019 High

    It was unknown which SPN components ILP1 physically contacts; site-specific in vivo crosslinking established that ILP1's C-terminal coiled-coil domain directly binds alveolins IMC3, IMC6, and IMC27 through distinct interfaces, placing ILP1 in the interconnected cytoskeletal network.

    Evidence Photoactivatable unnatural amino acid crosslinking in live parasites with domain deletion/mapping in Toxoplasma gondii

    PMID:31584943

    Open questions at the time
    • Functional consequence of disrupting individual ILP1-alveolin contacts not tested
    • Stoichiometry and higher-order assembly of the network not determined
  2. 2024 High

    How alveolin-domain interactions drive SPN filament formation was unresolved; mapping the IMC6 alveolin domain showed it contains multiple binding interfaces for both IMC3 and ILP1, providing direct evidence that these interactions mediate filament assembly in the network.

    Evidence In-cell unnatural amino acid photoreactive crosslinking of the IMC6 alveolin domain with deletion analyses in Toxoplasma gondii (peer-reviewed; preprint version 2023, PMID:37609316)

    PMID:39264987 PMID:37609316

    Open questions at the time
    • Precise contribution of ILP1 versus IMC3 to filament rigidity/architecture not separated
    • Structural model of the assembled alveolin filament not established

Mechanism profile

Synthesis pass · controlled-vocabulary classification
Partners
IMC27IMC3IMC6
Complex memberships
Subpellicular network / alveolin cytoskeletal network (with IMC3, IMC6, IMC27)

Evidence

Reading pass · 3 per-paper findings extracted from the source corpus
Year Finding Method Journal Conf PMIDs
2019 ILP1's C-terminal coiled-coil domain directly binds to alveolins IMC3 and IMC6, as well as IMC27, in the Toxoplasma IMC cytoskeletal network. Distinct regions of the C-terminal coiled-coil domain of ILP1 crosslink to IMC3 and IMC6; the IMC3 C-terminal domain and the IMC6 N-terminal domain are necessary for binding to ILP1. Photoactivatable unnatural amino acid (UAA) crosslinking system in live parasites, mapping binding interfaces between ILP1 and IMC3, IMC6, and IMC27 PLoS biology High 31584943
2024 The alveolin domain of IMC6 contains multiple binding interfaces with IMC3 and ILP1, providing direct evidence that protein-protein interactions within the alveolin domain mediate filament formation in the subpellicular network (SPN). ILP1 is thus a binding partner of IMC6 within the alveolin domain. Unnatural amino acid photoreactive crosslinking applied to the IMC6 alveolin domain; deletion analyses for localization and function PLoS biology High 39264987
2023 ILP1 is identified as a binding partner of IMC6 within the alveolin domain of the Toxoplasma subpellicular network, consistent with a role in maintaining SPN architecture and parasite shape. Unnatural amino acid photoreactive crosslinking of the IMC6 alveolin domain bioRxivpreprint Medium 37609316

Source papers

Stage 0 corpus · 12 papers · ranked by NIH iCite citations
Year Title Journal Citations PMID
2015 Novel components of the Toxoplasma inner membrane complex revealed by BioID. mBio 148 25691595
2009 A novel family of Apicomplexan glideosome-associated proteins with an inner membrane-anchoring role. The Journal of biological chemistry 102 19561073
2000 Microtubules, but not actin filaments, drive daughter cell budding and cell division in Toxoplasma gondii. Journal of cell science 95 10704375
2014 The inner membrane complex through development of Toxoplasma gondii and Plasmodium. Cellular microbiology 78 24612102
2014 Dynamics of the Toxoplasma gondii inner membrane complex. Journal of cell science 54 24928899
2012 Targeted proteomic dissection of Toxoplasma cytoskeleton sub-compartments using MORN1. Cytoskeleton (Hoboken, N.J.) 44 23027733
2019 A photoactivatable crosslinking system reveals protein interactions in the Toxoplasma gondii inner membrane complex. PLoS biology 33 31584943
2016 Virus-Like Nanoparticle Vaccine Confers Protection against Toxoplasma gondii. PloS one 33 27548677
2011 Subcellular antigen location influences T-cell activation during acute infection with Toxoplasma gondii. PloS one 33 21829561
2014 Identification and characterization of Toxoplasma SIP, a conserved apicomplexan cytoskeleton protein involved in maintaining the shape, motility and virulence of the parasite. Cellular microbiology 28 25088010
2024 Alveolin proteins in the Toxoplasma inner membrane complex form a highly interconnected structure that maintains parasite shape and replication. PLoS biology 10 39264987
2023 The Toxoplasma subpellicular network is highly interconnected and defines parasite shape for efficient motility and replication. bioRxiv : the preprint server for biology 3 37609316