A0A8J1IYX6 (LOC101732819) is an uncharacterized 424-residue serine/threonine protein kinase of the AGC kinase group in Xenopus tropicalis. Although the RefSeq-derived protein name is "Protein kinase C delta type", the protein lacks the C1 (diacylglycerol-binding) and C2-like regulatory domains that define PKC family kinases; its architecture comprises a long intrinsically disordered N-terminal region rich in basic and acidic residues (approximately residues 1-103), a single protein kinase domain (residues 113-366), and an AGC-kinase C-terminal extension (residues 367-424). PANTHER classifies the protein within the ribosomal protein S6 kinase family (PTHR24351), a clade of AGC kinases that includes the p70/p85 S6 kinases (S6K), p90 ribosomal S6 kinases (RSK), mitogen- and stress-activated kinases (MSK), and related fungal and protist kinases such as Sch9 and psk1. Members of this family are activated downstream of growth factor and nutrient signaling and phosphorylate serine/threonine residues on substrates in the cytoplasm and nucleus, regulating protein synthesis, cell growth, and transcription. No gene-specific experimental characterization of this Xenopus tropicalis protein has been published; its molecular function as an ATP-dependent protein serine/threonine kinase is inferred from domain architecture, conserved catalytic and ATP-binding motifs, and phylogenetic placement.
| GO Term | Evidence | Action | Reason |
|---|---|---|---|
| GO:0005634 nucleus | IBA GO_REF:0000033 | ACCEPT | Summary: PAINT phylogenetic inference (node PTN008614470) places nuclear activity on the family node containing this protein, with descendant experimental evidence from fission yeast (PomBase:SPCC24B10.07), budding yeast (SGD:S000004710), and other family members. Kinases of the ribosomal protein S6 kinase family (notably the RSK and MSK subfamilies) act in the nucleus, where they phosphorylate transcription-associated substrates, so nuclear activity is a phylogenetically plausible property of this uncharacterized family member. Reason: The IBA reflects a considered PAINT judgment placing nuclear activity at an ancestral node of the S6-kinase family, supported by experimental annotations on descendant members. There is no gene-specific evidence for or against nuclear localization of this protein, and no target-specific indication of loss, so the phylogenetic inference is retained as the best available evidence. Propagation Review Root cause: NO FAILURE NON CORE Sources checked: PANTHER:PTN008614470 · S6-kinase-family localization node (Eukaryota) SUPPORTS TRANSFER Node asserts is_active_in nucleus (IBD, paint snapshot 20260828); see PTHR24351-review.yaml, where this node is assessed UNRESOLVED -- defensible for the target's sub-clade but not positively confirmed, since nuclear localization is the least conserved of the propagated properties. PomBase:SPCC24B10.07 · fission yeast S6-kinase-family kinase SUPPORTS TRANSFER nuclear-localized fungal seed of the node. UniProtKB:Q582V7 · Trypanosoma brucei Ser/Thr kinase (putative) SUPPORTS TRANSFER SGD:S000004710 · budding yeast S6-kinase-family kinase SUPPORTS TRANSFER |
| GO:0005737 cytoplasm | IBA GO_REF:0000033 | ACCEPT | Summary: PAINT phylogenetic inference (node PTN008614470) places cytoplasmic activity on the family node containing this protein. Ribosomal protein S6 kinase family members characteristically act in the cytoplasm, where they phosphorylate substrates such as ribosomal protein S6 and other regulators of translation and cell growth. The protein has no signal peptide, transmembrane segment, or organellar targeting features, consistent with a soluble cytoplasmic kinase. Reason: Cytoplasmic activity is a conserved property of the S6-kinase family from which this annotation is propagated, and nothing in the sequence (no targeting signals) contradicts it. The PAINT inference is retained. Propagation Review Root cause: NO FAILURE NON CORE Sources checked: PANTHER:PTN008614470 · S6-kinase-family localization node (Eukaryota) SUPPORTS TRANSFER Node asserts is_active_in cytoplasm (IBD, paint snapshot 20260828); assessed SOUND in PTHR24351-review.yaml. Cytoplasm is the default, best- supported compartment for the soluble AGC kinases of this family. PomBase:SPCC24B10.07 · fission yeast S6-kinase-family kinase SUPPORTS TRANSFER UniProtKB:Q582V7 · Trypanosoma brucei Ser/Thr kinase (putative) SUPPORTS TRANSFER UniProtKB:Q8I4W3 · Plasmodium falciparum RAC-beta (Akt-like) kinase SUPPORTS TRANSFER |
| GO:0004674 protein serine/threonine kinase activity | IBA GO_REF:0000033 | ACCEPT | Summary: The protein carries a complete protein kinase domain (residues 113-366) with the PROSITE serine/threonine-kinase active-site signature (PS00108), an ATP-binding-site motif, and an AGC-kinase C-terminal domain. The PAINT node (PTN008614469) is seeded by extensive experimental annotations across the family, including human RSK/MSK/S6K kinases (UniProtKB:Q15418, O75582, O75676, P23443, Q9UBS0) and mouse, rat, fly, yeast, fission yeast, Dictyostelium, and plant members. Protein serine/threonine kinase activity is the core molecular function of the whole family. Reason: This is the primary molecular function inferred from domain architecture, conserved catalytic motifs, and phylogenetic placement within a family in which serine/threonine kinase activity is experimentally established in many descendants. Family-level inspection (PTHR24351-review.yaml) confirms the node placement is sound and the target retains the complete catalytic machinery: the VAIK beta-3 lysine (K142, its own UniProt ATP-binding feature), the HRD catalytic aspartate (D235, motif IHRDLKPDN at 232), and the DFG magnesium-binding aspartate (D253, motif ICDFG at 251). Propagation Review Root cause: NO FAILURE CORE Sources checked: PANTHER:PTN008614469 · S6-kinase family node for protein Ser/Thr kinase activity SUPPORTS TRANSFER IBD node (paint snapshot 20241120) seeded by experimentally characterized active kinases across the family; assessed SOUND in PTHR24351-review.yaml. The target is not among the seeds (it is uncharacterized), so there is no self-source to adjudicate. UniProtKB:P23443 · human S6K1 (RPS6KB1) SUPPORTS TRANSFER Best-characterized single-kinase-domain member; anchors the family catalytic_core residue site (VAIK K123 = UniProt BINDING/ATP, HRD D218 = UniProt ACT_SITE proton acceptor). UniProtKB:Q15418 · human RSK1 (RPS6KA1) SUPPORTS TRANSFER active member; N-terminal kinase-domain HRD aspartate D187 verified. UniProtKB:O75582 · human MSK1 (RPS6KA5) SUPPORTS TRANSFER UniProtKB:Q8I4W3 · Plasmodium falciparum RAC-beta (Akt-like) kinase SUPPORTS TRANSFER Supporting Evidence: file:XENTR/A0A8J1IYX6/A0A8J1IYX6-uniprot.txt Belongs to the protein kinase superfamily file:XENTR/A0A8J1IYX6/A0A8J1IYX6-uniprot.txt Serine/threonine-protein kinase |
| GO:0000166 nucleotide binding | IEA GO_REF:0000104 | MARK AS OVER ANNOTATED | Summary: The kinase does bind a nucleotide (ATP, as phosphate donor), but this term is far too general. The more specific ATP binding (GO:0005524) annotation is also present and provides much more biological specificity. Reason: GO:0000166 nucleotide binding is a very broad parent term that is redundant given the presence of the more informative GO:0005524 ATP binding annotation. |
| GO:0004672 protein kinase activity | IEA GO_REF:0000002 | MARK AS OVER ANNOTATED | Summary: The protein has protein kinase activity, but this term is a direct parent of the more specific GO:0004674 (protein serine/threonine kinase activity), which is also annotated via both IBA and IEA evidence. The InterPro signature underlying this annotation (IPR008271) is itself the serine/threonine-kinase active-site signature, so the more specific term is preferred. Reason: Redundant with the more specific GO:0004674 protein serine/threonine kinase activity annotation that is already present; the sequence carries the Ser/Thr-kinase active-site signature, not a tyrosine-kinase signature. Supporting Evidence: file:XENTR/A0A8J1IYX6/A0A8J1IYX6-uniprot.txt PROSITE; PS00108; PROTEIN_KINASE_ST |
| GO:0004674 protein serine/threonine kinase activity | IEA GO_REF:0000120 | ACCEPT | Summary: This duplicates the IBA-evidenced annotation for the same term. The combined IEA annotation from InterPro domain signatures (IPR000961 AGC-kinase C-terminal) and UniRule correctly identifies the core catalytic function from sequence features. Reason: Correctly identifies the core molecular function from domain signatures. Although this duplicates the IBA annotation, the independent computational evidence reinforces the annotation. Supporting Evidence: file:XENTR/A0A8J1IYX6/A0A8J1IYX6-uniprot.txt Serine/threonine-protein kinase |
| GO:0005524 ATP binding | IEA GO_REF:0000120 | KEEP AS NON CORE | Summary: The kinase binds ATP as the phosphate donor for its catalytic reaction. The UniProt entry records an ATP-binding site at position 142 within the protein kinase domain, supported by the InterPro protein kinase ATP binding site signature (IPR017441). ATP binding is mechanistically required for kinase activity. Reason: ATP binding is accurate and mechanistically essential, but it is functionally subsumed by the protein serine/threonine kinase activity annotation. ATP binding is a cofactor/substrate-binding property inherent to kinase function rather than an independent core function. Supporting Evidence: file:XENTR/A0A8J1IYX6/A0A8J1IYX6-uniprot.txt BINDING 142 /ligand="ATP" file:XENTR/A0A8J1IYX6/A0A8J1IYX6-uniprot.txt ATP-binding |
| GO:0016301 kinase activity | IEA GO_REF:0000104 | MARK AS OVER ANNOTATED | Summary: This is a very broad parent term encompassing all kinase activities (protein kinases, lipid kinases, sugar kinases, etc.). The protein is specifically a protein serine/threonine kinase, and the more specific term GO:0004674 is already annotated. Reason: GO:0016301 kinase activity is too general and is redundant with the more specific GO:0004674 protein serine/threonine kinase activity already present. |
| GO:0016740 transferase activity | IEA GO_REF:0000104 | MARK AS OVER ANNOTATED | Summary: This is the broadest ancestral term for all transferase activities. While the protein is technically a transferase (phosphotransferase), this term provides essentially no biological specificity and is fully subsumed by the more specific kinase and protein serine/threonine kinase activity annotations. Reason: GO:0016740 transferase activity is the broadest possible functional classification and is entirely redundant with the more informative GO:0004674 and GO:0016301 annotations. |
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Download this section (compressed HTML)These computational predictions are reviewed separately from the GOA annotation set used for this review. The assessments below are from this project and do not constitute official GO annotations or endorsement by GO/UniProt. They are not included in the existing annotation review above.
View prediction review YAML · A0A8J1IYX6-protnlm-predictions-review.yaml · Review status: COMPLETE
ProtNLM2 made no predictions (GO or subcellular location) for Protein kinase domain-containing protein (Xenopus). The model returned only a protein name.
Source documents: genes/XENTR/A0A8J1IYX6/A0A8J1IYX6-uniprot.txt · genes/XENTR/A0A8J1IYX6/A0A8J1IYX6-goa.tsv
No GO/EC predictions in the reviewed source.
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