id: A0BFB4 gene_symbol: A0BFB4 product_type: PROTEIN status: COMPLETE taxon: id: NCBITaxon:5888 label: Paramecium tetraurelia description: A0BFB4 (ORF GSPATT00028266001) is an uncharacterized 381-residue protein kinase from the ciliate Paramecium tetraurelia. Residues 96-348 form a protein kinase domain, and the catalytic motifs are intact (glycine-rich loop, beta3 lysine K125, HRD catalytic loop, DFG, APE). It is therefore predicted to be an active, ATP-dependent protein serine/threonine kinase. Outside the kinase domain there is only a ~95-residue N-terminal segment with no annotated domain and a short C-terminal tail. It has none of the C-terminal regions that canonical Atg1/ULK kinases use to assemble the autophagy-initiation complex. Its classification within the kinome is uncertain. PANTHER's reference tree grafts it into the Atg1/UNC-51 family (PTHR24348), but the current PANTHER HMM assigns it to PTHR44167 (CHK2/CDC7-related kinases), and a kinase-domain distance tree does not group it robustly with Atg1/ULK proteins. Its substrates, subcellular location and biological roles have not been studied. existing_annotations: - term: id: GO:0016020 label: membrane evidence_type: IBA original_reference_id: GO_REF:0000033 qualifier: is_active_in review: summary: Membrane association is propagated from the Atg1/ULK ancestral node PTN000681272, where it reflects Atg1/ULK recruitment to autophagic membranes. A0BFB4 lacks the module that mediates that recruitment and has no transmembrane or lipid-anchor features. action: MARK_AS_OVER_ANNOTATED reason: The membrane IBD sits on the same Atg1/ULK node (PTN000681272) as the phagophore assembly site and autophagosome IBDs, and its seeds are Atg1/ULK proteins (ULK1, ULK2, yeast ATG1, S. pombe Atg1). Atg1/ULK proteins reach membranes through their C-terminal domain and Atg13/Atg17-FIP200 partners. A0BFB4 lacks that domain, and ciliates lack the partners (PMID:28123910). The UniProt record has no transmembrane or signal features. The node placement itself is also weak at the sequence level (see the bioinformatics results). The earlier ACCEPT treated this term as generic, but it is one of the Atg1-node localization assertions and rests on the same inheritance argument as the phagophore-site term. It is therefore marked over-annotated rather than accepted. It is not removed, because a peripheral membrane association is not contradicted. supported_by: - reference_id: PMID:28123910 supporting_text: Atg1 complex members (Atg13, Atg17, Atg29, Atg31 in the yeast Atg1 complex; Atg13, Atg101 and FIP200 in the mammalian ULK1 complex) require the C-terminal domain of Atg1 to interact and form the complex reference_section_type: RESULTS - reference_id: file:PARTE/A0BFB4/A0BFB4-bioinformatics/RESULTS.md supporting_text: it does **not** support specific orthology to ATG1/ULK propagation_review: root_cause: PROPAGATION_BAD failure_modes: - COMPARTMENT_OR_COMPLEX_MISMATCH - FUNCTIONAL_DIVERGENCE source_entities: - source_id: PANTHER:PTN000681272 source_status: SUPPORTS_SOURCE_BUT_NOT_TARGET comment: Atg1/ULK node; membrane recruitment of the seed kinases depends on the C-terminal domain and complex partners that A0BFB4 and ciliates lack. - term: id: GO:0005737 label: cytoplasm evidence_type: IBA original_reference_id: GO_REF:0000033 qualifier: is_active_in review: summary: Cytoplasm is propagated from the deep PTHR24348 family node PTN002805221, not from the Atg1-specific node. It fits a soluble kinase-domain protein with no signal peptide or transmembrane segment. action: ACCEPT reason: This IBD sits at the family-level node PTN002805221, the same node that supplies protein serine/threonine kinase activity. Cytoplasmic residence of these kinases does not depend on the Atg1 C-terminal module. A0BFB4 has no predicted signal peptide, transmembrane helix or organellar targeting feature, so the inference is not contradicted. No experimental localization exists for A0BFB4 (the deep-research report found none). The term is as precise as the evidence allows. supported_by: - reference_id: file:PARTE/A0BFB4/A0BFB4-deep-research-falcon.md supporting_text: No direct localization data exist for protein A0BFB4. - reference_id: file:PARTE/A0BFB4/A0BFB4-bioinformatics/RESULTS.md supporting_text: A0BFB4 is an active-site-intact Ser/Thr kinase domain - term: id: GO:0000045 label: autophagosome assembly evidence_type: IBA original_reference_id: GO_REF:0000033 qualifier: involved_in review: summary: Over-propagated. Autophagosome assembly by Atg1/ULK needs the Atg1 complex, which cannot form here. A0BFB4 lacks the Atg1 C-terminal domain, ciliates lack Atg13, Atg17, FIP200 and Atg101, and A0BFB4 does not group robustly with Atg1/ULK by sequence. action: MARK_AS_OVER_ANNOTATED reason: The IBD at PTN000681272 is sound for Atg1/ULK proteins. Two lines of target-specific evidence argue against inheritance here. (1) Aslan et al. surveyed ciliate genomes, including Paramecium tetraurelia, and found that every Atg1-like kinase-domain protein lacks the Atg1-specific C-terminal domain needed to form the complex. The other Atg1-complex members are also absent. The authors conclude that these proteins should not be considered Atg1 candidates without experimental work (PMID:28123910). A0BFB4 has a C-terminal tail of only 33 residues after the kinase domain. (2) Membership of the Atg1 clade is itself doubtful. The current PANTHER HMM places A0BFB4 in PTHR44167, not PTHR24348. In the kinase-domain neighbour-joining analysis, A0BFB4 grouped exclusively with the ATG1/ULK kinases in only 1 of 200 bootstrap replicates. Kinase activity is retained, but participation in autophagosome assembly is not established. It is not removed outright because ciliates do have autophagy (PMID:24280724), and whether any ciliate Atg1-like kinase contributes to it remains open. supported_by: - reference_id: PMID:28123910 supporting_text: ciliate genomes do not encode typical Atg1 since all the candidate sequences lack an Atg1-specific C-terminal domain which is essential for Atg1 complex formation reference_section_type: ABSTRACT - reference_id: PMID:28123910 supporting_text: We conclude that these kinase domain containing proteins should not be considered as Atg1 candidates without further experimental analyses, since they all lack the important C-terminal domains. reference_section_type: RESULTS - reference_id: file:PARTE/A0BFB4/A0BFB4-bioinformatics/RESULTS.md supporting_text: bootstrap support for A0BFB4 + ATG1/ULK is 1/200 propagation_review: root_cause: PROPAGATION_BAD failure_modes: - FUNCTIONAL_DIVERGENCE - COMPARTMENT_OR_COMPLEX_MISMATCH source_entities: - source_id: PANTHER:PTN000681272 source_status: SUPPORTS_SOURCE_BUT_NOT_TARGET comment: Atg1/ULK node, correct for the seeds. The A0BFB4 leaf PTN002805316 grafted below it lacks the C-terminal complex-assembly domain, and its placement conflicts with the current HMM family PTHR44167. - term: id: GO:0010506 label: regulation of autophagy evidence_type: IBA original_reference_id: GO_REF:0000033 qualifier: involved_in review: summary: Over-propagated from the same Atg1/ULK node. No evidence ties A0BFB4 to autophagy regulation, and the inheritance argument is the same weak one behind the other autophagy rows. action: MARK_AS_OVER_ANNOTATED reason: The previous review left this row UNDECIDED because the term is broad enough to allow a noncanonical ciliate role. This re-review gives it the same action as the sister autophagy rows, because it rests on the same IBD source (PTN000681272) and the same weak Atg1-clade placement. The seed regulatory roles (ULK1, Drosophila Atg1) act through the Atg1 complex. Aslan et al. leave open whether any ciliate kinase-domain protein has an autophagic role (PMID:28123910). That possibility is not evidence for this protein, which has no perturbation, localization or interaction data. Ciliate autophagy-like programmed nuclear death runs through VPS34 and ATG8 (PMID:24280724), not through any characterized Atg1-like kinase. The row is kept as over-annotated rather than removed, pending Paramecium-specific data. supported_by: - reference_id: PMID:28123910 supporting_text: However, it is still an open question whether any of these kinase domain containing proteins have role(s) in autophagic processes in ciliates. reference_section_type: RESULTS - reference_id: PMID:28123910 supporting_text: Collectively, these results may imply that ciliates might have an Atg1-independent pathway for autophagy induction and autophagosome formation. reference_section_type: RESULTS - reference_id: PMID:24280724 supporting_text: Programmed nuclear death (PND) in the ciliate protozoan Tetrahymena thermophila is a novel type of autophagy that occurs during conjugation reference_section_type: ABSTRACT propagation_review: root_cause: PROPAGATION_BAD failure_modes: - FUNCTIONAL_DIVERGENCE source_entities: - source_id: PANTHER:PTN000681272 source_status: SUPPORTS_SOURCE_BUT_NOT_TARGET comment: The seeds regulate autophagy through the Atg1/ULK complex. No complex-independent regulatory role is documented for ciliate Atg1-like kinase-domain proteins. - term: id: GO:0000407 label: phagophore assembly site evidence_type: IBA original_reference_id: GO_REF:0000033 qualifier: is_active_in review: summary: Over-propagated. Atg1/ULK targeting to the phagophore assembly site depends on the C-terminal domain and partner complex, which A0BFB4 and ciliates lack. action: MARK_AS_OVER_ANNOTATED reason: The localization of the seed kinases (ULK1, ULK2, yeast ATG1) to the phagophore assembly site is mediated by Atg13 and Atg17/FIP200 binding to the Atg1 C-terminal domain. A0BFB4 lacks that domain, ciliates lack those partners, and A0BFB4's grouping with the Atg1/ULK clade is itself weak. No Paramecium localization data exist. supported_by: - reference_id: PMID:28123910 supporting_text: Consistent with the absence of Atg1, ciliates also lack other members of the Atg1 complex. reference_section_type: ABSTRACT - reference_id: PMID:28123910 supporting_text: Atg1 complex members (Atg13, Atg17, Atg29, Atg31 in the yeast Atg1 complex; Atg13, Atg101 and FIP200 in the mammalian ULK1 complex) require the C-terminal domain of Atg1 to interact and form the complex reference_section_type: RESULTS propagation_review: root_cause: PROPAGATION_BAD failure_modes: - COMPARTMENT_OR_COMPLEX_MISMATCH source_entities: - source_id: PANTHER:PTN000681272 source_status: SUPPORTS_SOURCE_BUT_NOT_TARGET comment: Atg1/ULK node. PAS targeting needs the C-terminal module, which is absent from A0BFB4. - term: id: GO:0005776 label: autophagosome evidence_type: IBA original_reference_id: GO_REF:0000033 qualifier: is_active_in review: summary: Over-propagated autophagosome localization, for the same reasons as the phagophore assembly site row. action: MARK_AS_OVER_ANNOTATED reason: The localization of the seed Atg1/ULK proteins to autophagosomes depends on Atg1 complex recruitment, which cannot occur through the canonical mechanism in ciliates. A0BFB4 has no membrane-binding features, does not group robustly with Atg1/ULK, and has no localization data. supported_by: - reference_id: PMID:28123910 supporting_text: ciliate genomes do not encode typical Atg1 since all the candidate sequences lack an Atg1-specific C-terminal domain which is essential for Atg1 complex formation reference_section_type: ABSTRACT - reference_id: file:PARTE/A0BFB4/A0BFB4-deep-research-falcon.md supporting_text: No direct localization data exist for protein A0BFB4. propagation_review: root_cause: PROPAGATION_BAD failure_modes: - COMPARTMENT_OR_COMPLEX_MISMATCH source_entities: - source_id: PANTHER:PTN000681272 source_status: SUPPORTS_SOURCE_BUT_NOT_TARGET comment: Atg1/ULK node. Autophagosome association of the seeds requires complex assembly that is absent in the ciliate target. - term: id: GO:0004674 label: protein serine/threonine kinase activity evidence_type: IBA original_reference_id: GO_REF:0000033 qualifier: enables review: summary: Core function. It is propagated from the deep PTHR24348 node PTN002805221 and matches the intact Ser/Thr kinase catalytic machinery of A0BFB4. action: ACCEPT reason: This MF IBD sits at the family-level node PTN002805221 and is independent of the Atg1-specific placement debated above. A0BFB4 keeps every canonical catalytic motif (GEGTFG glycine-rich loop, K125, HRDIKPDN catalytic loop, DFG, APE) and the PROSITE Ser/Thr active-site signature. Protein serine/threonine kinase activity is also the conserved activity of PTHR44167, the family to which the current HMM assigns A0BFB4. The MF holds whichever classification is right. supported_by: - reference_id: file:PARTE/A0BFB4/A0BFB4-bioinformatics/RESULTS.md supporting_text: All canonical kinase catalytic motifs are present in A0BFB4 - reference_id: file:PARTE/A0BFB4/A0BFB4-uniprot.txt record_section: ["DR:InterPro"] supporting_text: Ser/Thr_kinase_AS. - term: id: GO:0005829 label: cytosol evidence_type: IBA original_reference_id: GO_REF:0000033 qualifier: is_active_in review: summary: Cytosol is propagated from PTN000681272, but it reflects the soluble character of these kinases rather than complex-dependent targeting. It is plausible for A0BFB4 and kept as non-core. action: KEEP_AS_NON_CORE reason: Unlike the phagophore and autophagosome terms, cytosolic residence of the seed kinases does not depend on the missing C-terminal module. A soluble kinase-domain protein with no targeting features is expected to reside in the cytosol. There is no direct localization evidence, and the source node is the debated Atg1/ULK node. The term is therefore kept, but not treated as part of the core description. supported_by: - reference_id: file:PARTE/A0BFB4/A0BFB4-deep-research-falcon.md supporting_text: No direct localization data exist for protein A0BFB4. - reference_id: file:PARTE/A0BFB4/A0BFB4-uniprot.txt record_section: ["CC:SIMILARITY"] supporting_text: Belongs to the protein kinase superfamily. - term: id: GO:0000166 label: nucleotide binding evidence_type: IEA original_reference_id: GO_REF:0000104 qualifier: enables review: summary: True but general. The supported nucleotide is ATP, through the conserved kinase ATP-binding site. action: MODIFY reason: The PROSITE ATP-binding signature and K125 identify the bound nucleotide as ATP. ATP binding (GO:0005524), which this gene already carries, is the specific supported term. proposed_replacement_terms: - id: GO:0005524 label: ATP binding supported_by: - reference_id: file:PARTE/A0BFB4/A0BFB4-uniprot.txt record_section: ["DR:InterPro"] supporting_text: Protein_kinase_ATP_BS. - term: id: GO:0004672 label: protein kinase activity evidence_type: IEA original_reference_id: GO_REF:0000002 qualifier: enables review: summary: True but general. The Ser/Thr active-site signature supports the more specific protein serine/threonine kinase activity. action: MODIFY reason: The PROSITE Ser/Thr kinase active-site signature (PS00108) and the HRDIKPDN catalytic loop specify Ser/Thr phosphorylation. GO:0004674, which this gene already carries, is the specific supported descendant. proposed_replacement_terms: - id: GO:0004674 label: protein serine/threonine kinase activity supported_by: - reference_id: file:PARTE/A0BFB4/A0BFB4-uniprot.txt record_section: ["DR:InterPro"] supporting_text: Ser/Thr_kinase_AS. - term: id: GO:0004674 label: protein serine/threonine kinase activity evidence_type: IEA original_reference_id: GO_REF:0000120 qualifier: enables review: summary: Same core MF as the IBA row, here from the combined automated (UniRule/EC) pipeline. action: ACCEPT reason: This row agrees with the IBA row for the same term and is supported by the intact Ser/Thr kinase catalytic motifs. supported_by: - reference_id: file:PARTE/A0BFB4/A0BFB4-uniprot.txt record_section: ["DR:InterPro"] supporting_text: Ser/Thr_kinase_AS. - reference_id: file:PARTE/A0BFB4/A0BFB4-bioinformatics/RESULTS.md supporting_text: The protein is predicted to be a catalytically competent serine/threonine kinase, not a pseudokinase. - term: id: GO:0005524 label: ATP binding evidence_type: IEA original_reference_id: GO_REF:0000120 qualifier: enables review: summary: ATP binding by the conserved kinase ATP site (glycine-rich loop GEGTFG and K125). action: ACCEPT reason: The PROSITE ATP-binding signature, the glycine-rich loop and the beta3 lysine K125 (annotated by PROSITE-ProRule as the ATP-binding residue) are all present. ATP binding is intrinsic to the kinase's catalytic activity. supported_by: - reference_id: file:PARTE/A0BFB4/A0BFB4-uniprot.txt record_section: ["DR:InterPro"] supporting_text: Protein_kinase_ATP_BS. - reference_id: file:PARTE/A0BFB4/A0BFB4-bioinformatics/RESULTS.md supporting_text: beta3 lysine motif ACK at 123 (K125, the UniProt ATP-binding residue) - term: id: GO:0016301 label: kinase activity evidence_type: IEA original_reference_id: GO_REF:0000104 qualifier: enables review: summary: True but general. Refine to protein serine/threonine kinase activity. action: MODIFY reason: The kinase domain has the protein-kinase fold and the Ser/Thr active-site signature, so the supported specific term is GO:0004674, which this gene already carries. proposed_replacement_terms: - id: GO:0004674 label: protein serine/threonine kinase activity supported_by: - reference_id: file:PARTE/A0BFB4/A0BFB4-uniprot.txt record_section: ["DR:InterPro"] supporting_text: Ser/Thr_kinase_AS. - term: id: GO:0016740 label: transferase activity evidence_type: IEA original_reference_id: GO_REF:0000104 qualifier: enables review: summary: True but very general. Refine to protein serine/threonine kinase activity. action: MODIFY reason: The transferase activity of A0BFB4 is phosphotransfer from ATP to protein Ser/Thr residues. GO:0004674, already carried, is the specific supported descendant. proposed_replacement_terms: - id: GO:0004674 label: protein serine/threonine kinase activity supported_by: - reference_id: file:PARTE/A0BFB4/A0BFB4-uniprot.txt record_section: ["DR:InterPro"] supporting_text: Ser/Thr_kinase_AS. core_functions: - description: Predicted ATP-dependent protein serine/threonine kinase activity of a kinase domain with intact catalytic motifs. Substrates, pathway and location are unknown, and no Atg1/ULK-complex role is established. molecular_function: id: GO:0004674 label: protein serine/threonine kinase activity locations: - id: GO:0005737 label: cytoplasm supported_by: - reference_id: file:PARTE/A0BFB4/A0BFB4-bioinformatics/RESULTS.md supporting_text: All canonical kinase catalytic motifs are present in A0BFB4 - reference_id: file:PARTE/A0BFB4/A0BFB4-uniprot.txt record_section: ["DR:InterPro"] supporting_text: Protein_kinase_ATP_BS. - reference_id: file:PARTE/A0BFB4/A0BFB4-uniprot.txt record_section: ["DR:InterPro"] supporting_text: Ser/Thr_kinase_AS. references: - id: GO_REF:0000002 title: Gene Ontology annotation through association of InterPro records with GO terms findings: [] - id: GO_REF:0000033 title: Annotation inferences using phylogenetic trees findings: [] - id: GO_REF:0000104 title: Electronic Gene Ontology annotations created by transferring manual GO annotations between related proteins based on shared sequence features findings: [] - id: GO_REF:0000120 title: Combined Automated Annotation using Multiple IEA Methods findings: [] - id: file:PARTE/A0BFB4/A0BFB4-uniprot.txt title: UniProtKB A0BFB4 sequence and domain record reference_review: relevance: HIGH correctness: VERIFIED review_notes: Unreviewed TrEMBL entry for GSPATT00028266001/CAK57231.1 (381 aa, canonical and only product). Protein kinase domain 96-348, ATP-binding-site and Ser/Thr-active-site PROSITE signatures, and PANTHER cross-reference PTHR44167:SF18 were checked against the file. GO lines are not used as evidence. - id: file:PARTE/A0BFB4/A0BFB4-deep-research-falcon.md title: Falcon research on A0BFB4/GSPATT00028266001 reference_review: relevance: MEDIUM correctness: UNVERIFIED review_notes: Read the complete report. It found no target-specific experiments; it is cited only for the absence of substrate and localization data. Its discussion of general Paramecium kinome, Ca2+ signaling and ciliary pathways is context and does not assign this protein to a pathway. findings: - statement: Target substrates are unresolved despite a supported catalytic architecture. supporting_text: The specific substrates of A0BFB4 are unknown. - statement: The provider does not establish a target pathway or localization experimentally. supporting_text: No direct localization data exist for protein A0BFB4. - id: PMID:28123910 title: A comparative in-silico analysis of autophagy proteins in ciliates. findings: - statement: Ciliate genomes, including Paramecium tetraurelia, lack typical Atg1 proteins with the C-terminal domain needed for Atg1-complex assembly. supporting_text: ciliate genomes do not encode typical Atg1 since all the candidate sequences lack an Atg1-specific C-terminal domain which is essential for Atg1 complex formation reference_section_type: ABSTRACT - statement: Ciliates also lack Atg1-complex partners, supporting lineage-level loss of the canonical Atg1 initiation machinery. supporting_text: Consistent with the absence of Atg1, ciliates also lack other members of the Atg1 complex. reference_section_type: ABSTRACT - statement: Ciliate Atg1-like kinase-domain proteins should not be treated as Atg1 without experiments, and whether any of them acts in ciliate autophagy is an open question. supporting_text: However, it is still an open question whether any of these kinase domain containing proteins have role(s) in autophagic processes in ciliates. reference_section_type: RESULTS reference_review: relevance: HIGH correctness: VERIFIED review_notes: Full text cached and read. It explicitly surveys Paramecium tetraurelia. PSI-BLAST with yeast Atg1 hits only the kinase domain in ciliates, and the Atg1 C-terminal region has no ciliate hits. - id: PMID:24280724 title: Role of class III phosphatidylinositol 3-kinase during programmed nuclear death of Tetrahymena thermophila. findings: - statement: Tetrahymena programmed nuclear death is a ciliate autophagy-like process, supporting residual uncertainty about noncanonical ciliate autophagy regulation. supporting_text: Programmed nuclear death (PND) in the ciliate protozoan Tetrahymena thermophila is a novel type of autophagy that occurs during conjugation reference_section_type: ABSTRACT reference_review: relevance: MEDIUM correctness: VERIFIED review_notes: Tetrahymena paper. It shows that ciliates have autophagy-like processes that depend on VPS34, but it does not implicate A0BFB4 or any Atg1-like kinase. - id: file:PARTE/A0BFB4/A0BFB4-placement-evidence.md title: A0BFB4 verified PAINT descent and sequence-family discrepancy reference_review: relevance: HIGH correctness: DISPUTED review_notes: Records that the PANTHER PTHR24348 reference tree has A0BFB4 as leaf PTN002805316 below the Atg1/ULK node PTN000681272, and that the current HMM gives PTHR44167:SF18. The tree lineage is accepted as a description of the PANTHER graft. Its 2026-09-20 conclusion that the autophagy terms are inherited is superseded by its own 2026-10-10 addendum and by this re-review's kinase-domain analysis. No longer cited as positive support for any annotation. findings: - statement: The actual tree places A0BFB4 below the autophagy-bearing ancestor; this is not merely a donor-list inference. supporting_text: The actual tree therefore confirms that A0BFB4 descends from the autophagy-bearing ancestral node. - id: file:PARTE/A0BFB4/A0BFB4-hypotheses/autophagy-ancestry-versus-hmm-family-placement/openscientist.md title: OpenScientist focused report on A0BFB4 autophagy ancestry versus family placement publication_type: DEEP_RESEARCH findings: - statement: The focused report found that PTHR44167 is a generic best-HMM hit rather than a competing family placement, leaving A0BFB4 in the Atg1/ULK clade. supporting_text: A0BFB4 genuinely belongs to the ATG1/ULK clade by ancestry, and this ancestry is **not** a misplacement. reference_section_type: RESULTS finding_review: finding_status: DISPUTED supported_by: - reference_id: file:PARTE/A0BFB4/A0BFB4-bioinformatics/RESULTS.md supporting_text: bootstrap support for A0BFB4 + ATG1/ULK is 1/200 - statement: The focused report interpreted the autophagosome-assembly, regulation-of-autophagy, phagophore-assembly-site, and autophagosome IBAs as over-specific because the ciliate lineage and the A0BFB4 protein lack the canonical Atg1/ULK initiation-complex module. supporting_text: Because the machinery that nucleates a phagophore is absent in the ciliate lineage and in this protein specifically, GO:0000045, GO:0000407, GO:0005776, and GO:0010506 rest solely on phylogenetic IBA inference and cannot be executed by the canonical mechanism. reference_section_type: RESULTS reference_review: relevance: MEDIUM correctness: DISPUTED review_notes: Its conclusion on the autophagy BP/CC terms agrees with this re-review and with PMID:28123910. Its claim that PTHR44167 is a function-less catch-all is wrong. The PTHR44167 family review describes it as the CHK2/Rad53 and CDC7/DDK kinase family. Its ULK-ancestry claim rests on a ~35% best-hit identity that this re-review could not reproduce as a discriminating signal (24.8-32.0% to all panel kinases). No longer cited as support for any annotation row. It is kept for provenance. - id: file:PARTE/A0BFB4/A0BFB4-bioinformatics/RESULTS.md title: A0BFB4 kinase-domain placement and catalytic motifs (2026-10-21 re-review) reference_review: relevance: HIGH correctness: VERIFIED review_notes: Reproducible scripts in the same folder (kinase_domain_placement.py, catalytic_motifs.py). This is a small-panel NJ analysis, not a full kinome phylogeny. findings: - statement: A0BFB4 retains all canonical kinase catalytic motifs. supporting_text: All canonical kinase catalytic motifs are present in A0BFB4 - statement: A0BFB4 does not group robustly with Atg1/ULK kinases in a kinase-domain NJ tree. supporting_text: bootstrap support for A0BFB4 + ATG1/ULK is 1/200 suggested_questions: - question: Should A0BFB4 remain a PAINT tree member of PTHR24348 below the Atg1/ULK node PTN000681272 when the current PANTHER HMM assigns it to PTHR44167:SF18? If the graft stands, can the Atg1-node BP/CC IBDs (autophagosome assembly, regulation of autophagy, phagophore assembly site, autophagosome, membrane) be blocked for ciliate kinase-domain-only descendants while the kinase MF is kept? - question: Which PANTHER family do the many Paramecium and Tetrahymena paralogs of A0BFB4 fall into, and does a full kinome phylogeny place this ciliate expansion inside the Atg1/ULK clade, the CAMK/CHK clade, or as a ciliate-specific group? - question: What, if anything, does the ~95-residue N-terminal segment before the kinase domain contribute (regulation, localization, partner binding)? suggested_experiments: - hypothesis: A0BFB4 is an active protein serine/threonine kinase. description: Express the recombinant kinase domain with a K125A (ATP-site lysine) control and measure autophosphorylation and phosphorylation of generic substrates (MBP, histone H1); then use peptide-library profiling to define its phosphosite motif. experiment_type: In vitro kinase assay - hypothesis: A0BFB4 contributes to a noncanonical Paramecium autophagy-like process. description: Deplete A0BFB4 and its closest ohnologs by RNAi feeding during starvation and autogamy, and quantify ATG8 puncta and old-macronucleus degradation against controls. experiment_type: RNAi phenotype assay - hypothesis: A0BFB4 localizes to the cytoplasm and not to autophagic membranes. description: Express GFP-tagged A0BFB4 and image it in vegetative, starved and autogamous cells, co-imaging with an ATG8 marker. experiment_type: Live-cell localization