CSPP1

Summary: Spindle-pole localization is inherited from the experimentally grounded ancestral node.

Reason: Spindle-pole localization is independently supported by human endogenous CSPP-L immunofluorescence in PMID:19129481. The actual PTN001091588 ancestral assertion is on the human target path. The target appearing among descendant evidence is expected, not circular.

Summary: Human CSPP-L localizes to spindle poles.

Reason: The original PMID:19129481 Results report endogenous human CSPP at spindle poles and colocalization with gamma-tubulin in HeLa cells. Its N-terminal antibody recognizes CSPP-L and does not recognize CSPP-S. This directly supports the location without assuming all three current human products were assayed; the separately described mouse constructs are not current human isoform numbers.

Summary: The combined mapping correctly captures spindle-pole localization.

Reason: The combined family/location mapping agrees with direct human CSPP-L spindle-pole localization. Retain the location; the actual IPR026708 outputs include spindle pole, and the official target location record includes the mapped subcellular term.

Summary: CSPP1 isoform 2 has a positive binary interaction with MRFAP1L1.

Reason: PMID:25416956 generated a systematic human ORF yeast two-hybrid map, with fresh-colony pairwise retesting and sequence confirmation. Three exact curated assay records join the seeded Q1MSJ5-2–Q96HT8 pair, and both participant sequence checksums match official sequences. Dataset-level orthogonal validation is not a separate validation claim for this pair. MRFAP1L1 has no sufficiently established functional class here to justify a more specific partner-binding term. Retain the positive interaction as non-core under the project policy; neither expected compartment nor generic wording invalidates the assay.

Summary: The short CSPP1 product interacts with RPGRIP1 in the binary screen.

Reason: The source explicitly identifies Q1MSJ5-2 and RPGRIP1/Q96KN7, supported by three exact PMID:25416956 yeast two-hybrid records with independently matched participant sequences. RPGRIP1 is distinct from RPGRIP1L. Its reviewed scaffolding/localization description does not establish a precise binding class for this assay; retain positive protein binding as non-core without inferring a native retinal complex, exclusivity to this isoform, or an RPGRIP1L experiment.

Summary: CSPP1 associates with the microtubule regulator CEP104.

Reason: The exact PMID:26638075 record is BioID proximity labeling, not a purified binary binding measurement. The available main Results and Methods describe the centrosome–cilium proximity network, control filtering and SAINT criteria. Independent PMID:32453716 reciprocal tagged co-immunoprecipitation supports the CSPP1–CEP104 association. CEP104 regulates ciliary axonemal organization, supporting the current GO:0005519 partner class. This refinement combines the interaction and partner-class premises without turning BioID into direct-contact evidence or assigning CEP104 activity to CSPP1. PMID:39856351 additionally reconstitutes cooperative CEP104/CSPP1 inhibition of microtubule growth and maps CEP104 JR-domain-dependent recruitment; it strengthens the regulatory context without converting this original proximity assertion into a direct-contact assay.

Proposed replacements: cytoskeletal regulatory protein binding

Summary: The CCDC66 interaction can be described by its cytoskeletal regulatory class.

Reason: PMID:32453716 main Results and Supplemental Figure 1 report reciprocal co-immunoprecipitation of tagged CSPP1 and CCDC66 in HEK293T cells. PMID:36606424 independently shows endogenous CSPP1 copelleting with GFP–CCDC66 and describes domain-dependent association. CCDC66 regulates microtubule organization and ciliary axonemal length; GO:0005519 therefore captures the experimentally supported partner class. These cellular assays do not establish purified pairwise contact or a fixed module stoichiometry. PMID:39856351 confirms CCDC66 microtubule-regulatory activity but does not observe CSPP1 colocalization with CCDC66 in the tested reconstitution conditions. This negative result is retained alongside the positive cellular associations; purified direct CSPP1–CCDC66 contact remains unestablished.

Proposed replacements: cytoskeletal regulatory protein binding

Summary: The CEP104 interaction supports cytoskeletal regulatory protein binding.

Reason: PMID:32453716 reports reciprocal tagged CSPP1–CEP104 co-immunoprecipitation in HEK293T cells (Supplemental Figure 1C/F and its Methods). Its mechanistic context identifies CEP104 as an axonemal microtubule regulator. GO:0005519 specifies that partner class without treating the interaction as tubulin binding or equating a cellular co-complex assay with purified direct contact. PMID:39856351 additionally shows cooperative CEP104/CSPP1 inhibition of microtubule growth and JR-domain-dependent recruitment. The new reconstitution supports the partner-class context while the original source remains a tagged cellular association assay.

Proposed replacements: cytoskeletal regulatory protein binding

Summary: ARMC9 is a cytoskeletal regulatory interaction partner of CSPP1.

Reason: PMID:32453716 identifies CSPP1 in the ARMC9 yeast two-hybrid screen and confirms association by reciprocal tagged co-immunoprecipitation. PMID:39856351 confirms and maps the association, shows CSPP1-dependent recruitment of ARMC9 to microtubules, and measures partner-dependent changes in pausing and TOGARAM1-mediated rescue. ARMC9 lacks autonomous microtubule binding in the tested conditions, but performs a regulatory scaffold role in the reconstituted system. GO:0005519 describes binding a protein that modulates cytoskeletal reorganization; intrinsic microtubule binding by that partner is not required. This refinement combines the actual interaction and performed regulatory role without assigning an autonomous enzyme or polymerase activity to CSPP1 or ARMC9.

Proposed replacements: cytoskeletal regulatory protein binding

Summary: TOGARAM1 is a cytoskeletal regulatory interaction partner of CSPP1.

Reason: The two raw GOA records collapse to one identical seeded source object for this PMID:32453716 interaction. The original supplementary reciprocal co-immunoprecipitation experiments support association of tagged CSPP1 and TOGARAM1 in HEK293T cells. The same study tests human TOGARAM1 perturbations and expression constructs affecting axonemal length and stability. GO:0005519 captures the partner class while preserving the cellular association scope; it does not claim that CSPP1 itself is a TOG-domain polymerase. PMID:39856351 does not reproduce CSPP1–TOGARAM1 co-immunoprecipitation or their colocalization in reconstitution. That study uses mouse TOGARAM1 with human CSPP1, whereas the earlier positive human cellular assays retain their own construct context. These differing results leave direct contact unresolved; they do not erase the original association or TOGARAM1’s demonstrated microtubule-regulatory class.

Proposed replacements: cytoskeletal regulatory protein binding

Summary: CCDC66 binding is supported independently in the ciliary context.

Reason: Actual PMID:36606424 Results and Figure 5 describe CSPP1 copelleting with GFP–CCDC66 but not GFP in HEK293T cells, with altered recovery for CCDC66 fragments. The mouse IMCD3 proximity screen is a separate experiment. CCDC66 is a microtubule-associated regulator of cilium length, allowing GO:0005519 refinement at partner-class scope. Satellite dependence and the unresolved direct-contact mechanism are retained; ciliary colocalization alone is not the binding premise. PMID:39856351 additionally establishes CCDC66 effects on microtubule dynamics but finds no CSPP1 colocalization with CCDC66 in reconstitution. Retain both the original positive cellular association and this negative assay boundary; no purified direct contact is inferred.

Proposed replacements: cytoskeletal regulatory protein binding

Summary: The ancestral centrosome assertion is retained.

Reason: Centrosome association is supported by human CSPP-L localization in PMID:19129481 and low-expression mNG-CSPP-L in human RPE-1 cells in PMID:36752787. The literal PTN001091588 IBD is on the human target path; a human descendant donor is legitimate evidence.

Summary: CSPP1 is detected at centrosomes in human cells.

Reason: The actual HPA antibody HPA056174 ICC/IF records identify centrosomal staining in A-431, HEK293 and U2OS cells, with supported assay validation and approved integrated reliability. Centrosomal localization is also independently supported by PMID:19129481. Other HPA locations in ciliated cell lines do not negate this context-dependent centrosomal pool. No product-specific assignment is inferred from a shared antibody epitope.

Summary: Retain the established centrosomal localization with explicit proteomics source limits.

Reason: PMID:21399614 is the authentic human centrosome study combining KE37 PCP-SILAC proteomics and antibody-based localization screens. Relevant original main Methods and Results were read, but the target-specific supplementary spreadsheet could not be recovered from the available routes; no CSPP1-specific spectrum or image is claimed. The existing curator-assigned IDA is biologically corroborated by direct PMID:19129481 and HPA localization, so retain centrosome while marking the unresolved source-level target verification explicitly rather than alleging misattribution.

Summary: The centrosome mapping agrees with direct human localization.

Reason: The centrosome family/location mapping is consistent with direct human CSPP-L localization. In the 2023 low-expression RPE-1 model, centrosomes and centriolar satellites are distinguished from cytoplasmic microtubules; PCM1 depletion redistributes CSPP-L. No uniform localization across cell states or products is inferred.

Summary: Human CSPP-L localizes to the mitotic spindle.

Reason: The original PMID:19129481 Results place endogenous human CSPP-L at the central spindle as well as poles in HeLa cells. The broad spindle term is supported; it is not replaced by spindle pole alone because the original explicitly reports both sites. Mouse fragment localization is kept distinct.

Summary: The mapped spindle location remains supported.

Reason: Retain the spindle mapping, corroborated by human CSPP-L central-spindle and pole localization in PMID:19129481. The annotation need not be narrowed solely to the pole, which would lose experimentally reported nonpolar spindle localization.

Summary: CSPP1 directly associates with microtubules.

Reason: Microtubule association is directly supported by purified human CSPP-L and CSPP-S constructs and by cellular experiments in PMID:36752787 and PMID:38389254. Cryo-ET and MINFLUX support luminal association in defined reconstitution and fragment-expression conditions. This does not imply every cellular centrosomal CSPP1 molecule lies within a microtubule lumen.

Summary: CSPP1 localizes along the primary cilium in the assayed human cells.

Reason: PMID:36606424 directly quantifies ciliary mNeonGreen–CSPP1 in serum-starved human RPE1 cells using the ARL13B-defined ciliary region. The tagged pool and its increased ciliary abundance after CCDC66 depletion are explicit; the separate mouse IMCD3 proximity experiment is not substituted for this human imaging result. The source does not identify an official product number for this localization annotation. Ciliary localization is independently consistent with patient-cell work in PMID:24360807.

Summary: CSPP-L localizes to primary cilia.

Reason: Ciliary localization is directly corroborated by low-expression mNG-CSPP-L in serum-starved human RPE-1 cells in PMID:36752787. The broader cilium term is appropriate; ciliary-tip and basal-body turnover differ, and localization alone is not treated as proof of every ciliary process.

Summary: The cytokinesis role has target-specific grounding at the ancestral node.

Reason: Positive regulation of cytokinesis has target-specific experimental grounding in PMID:19129481: human CSPP-L depletion produces furrow regression and displaces MyoGEF from the central spindle despite largely preserved central-spindle structure. CSPP1 performs a recruitment/organization role, not RhoA exchange catalysis. The exact PTN001091588 IBD is on the human target path; target-as-descendant evidence is not circular. This mitotic role does not imply an indispensable proliferation requirement in every cell type.

Summary: The family-based cytokinesis assertion is supported.

Reason: Retain the family-based cytokinesis assertion as independently corroborated by human CSPP-L depletion and MyoGEF localization experiments in PMID:19129481. The performed recruitment role supports regulation rather than merely reflecting a nonspecific proliferation defect. The actual IPR026708 output includes GO:0032467; no autonomous GEF activity is inferred.

Summary: CSPP-L promotes cytokinesis through MyoGEF recruitment.

Reason: The original PMID:19129481 reports furrow regression in 8 of 55 CSPP-L-depleted HeLa cells versus 0 of 50 controls, with central-spindle formation preserved in 65 examined cells. Depletion impairs central-spindle MyoGEF recruitment and local RhoA/myosin organization. This supports the positive regulatory assertion at its actual cell/isoform scope; it does not establish CSPP1 as a GEF or universally essential for proliferation.

Summary: Tagged CSPP1 self-association is experimentally supported.

Reason: PMID:32453716 Supplemental Figure 1C/F and the corresponding co-immunoprecipitation Methods show recovery of differently tagged CSPP1 constructs together in HEK293T cells, with mRFP controls and reciprocal assays. This supports identical protein binding, without proving a purified homodimer, a particular native oligomer stoichiometry or equivalence among the three official products. Retain this measured association as non-core beside the directly established microtubule mechanism.

Summary: Refine cell division to the directly supported cytokinesis role.

Reason: The most specific supported division phenotype in the original PMID:19129481 is impaired cytokinesis, with furrow regression and defective MyoGEF recruitment after human CSPP-L depletion. Refine the broad cell-division assertion to the existing cytokinesis term. This is a refinement of a source assertion, not a redundant NEW process proposal, and does not deny the separately reported mitotic arrest phenotype.

Proposed replacements: positive regulation of cytokinesis

Summary: CSPP-L directly stabilizes microtubules.

Reason: Purified human CSPP-L in reconstitution suppresses shrinkage and catastrophe and promotes pausing; cryo-ET/MINFLUX localize the protein within the microtubule lumen. Independent full-length 1221-aa CSPP1 experiments in PMID:38389254 demonstrate catastrophe suppression and resistance to MCAK-mediated depolymerization, with additional cellular depletion support. This is a directly performed molecular activity absent from the 25 seeded source rows. The tested long isoform is recorded; the 1256-aa displayed product is not claimed equivalent. CSPP1 does not exclude MCAK binding. The stabilizer term is appropriate despite the parent definition wording: its own defining SSNA1 paper likewise reports stabilization while permitting the destabilizing enzyme to remain bound. No redundant binding or NEW process term is added. PMID:39856351 additionally measures reduced growth, pausing and regrowth with CSPP1, and cooperative regulation with other ciliary tip proteins. Those tagged-protein experiments use porcine brain tubulin and mouse TOGARAM1 among otherwise human module proteins; they do not establish identical behavior of every official CSPP1 product or directly reconstitute human axonemes.