AMTN

Summary: No molecular function data. Superseded by direct evidence of hydroxyapatite binding, added as a NEW row; the ND placeholder is removed.

Reason: Recombinant human AMTN binds hydroxyapatite [PMID:25407797 "The binding affinity of rh-AMTN to HA was found to be comparable to that of amelogenin, the major protein of the forming enamel matrix."] and promotes its precipitation, through a phosphorylatable SSEEL motif [PMID:25407797 "Site-specific mutagenesis of the potential serine phosphorylation motif SSEEL reduced the in vitro mineral precipitation to less than 25%, revealing that this motif is important for the HA mineralizing function of the protein."]; it directly influences biomineralization [PMID:25407797 "These findings demonstrate that AMTN has a direct influence on biomineralization by promoting HA mineralization"]. In vivo, Amtn-null mice have defective surface enamel [PMID:25715379 "These observations indicate that AMTN plays a subtle yet critical role in enamel biomineralization, particularly during the establishment of the outer and surface enamel layers."], and a human AMTN deletion lowers enamel mineral density [PMID:27412008 "Exfoliated primary teeth from an affected family member had enamel that was of a lower mineral density compared to control enamel"]. The ND row predates this evidence; the activity is recorded by the NEW GO:0046848 row.

Summary: Protein binding with FAM20C, the secretory kinase that phosphorylates enamel matrix proteins. AMTN is its substrate; the binding records a kinase-substrate relationship, not an AMTN function. Removed.

Reason: The study concerns FAM20A/FAM20C phosphorylation of enamel matrix proteins [PMID:25789606 "Here we show that Fam20A potentiates Fam20C kinase activity and promotes the phosphorylation of enamel matrix proteins in vitro and in cells."]. AMTN is the substrate; the activity is the kinase's. Per the project's GO:0005515 policy the generic term is removed when no informative replacement is supported; removal is not a claim that the interaction is false.

Summary: Generic protein binding with BAG6, from HuRI. Uninformative; removed.

Reason: A proteome-scale screen [PMID:32296183 "Here we present a human 'all-by-all' reference interactome map of human binary protein interactions, or 'HuRI'."]. Per the project's GO:0005515 policy the generic term is removed when no informative replacement is supported; removal is not a claim that the interaction is false.

Summary: Extracellular region: AMTN is a secreted protein. Accepted.

Reason: AMTN is a secreted protein [PMID:16304441 "Amelotin protein was efficiently secreted from transfected cells in culture."] of the basal lamina between maturation-stage ameloblasts and enamel [PMID:16787391 "immunofluorescence localization within the rat and mouse mandibles revealed Amtn localized to the basal lamina of maturation stage ameloblasts of incisors and unerupted molars."].

Summary: Extracellular region, by similarity to mouse. Accepted.

Reason: AMTN is a secreted protein [PMID:16304441 "Amelotin protein was efficiently secreted from transfected cells in culture."] of the basal lamina between maturation-stage ameloblasts and enamel [PMID:16787391 "immunofluorescence localization within the rat and mouse mandibles revealed Amtn localized to the basal lamina of maturation stage ameloblasts of incisors and unerupted molars."].

Summary: Basement membrane, inherited through the PANTHER node. AMTN sits in the basal lamina at the ameloblast-enamel interface; accepted.

Reason: AMTN is a secreted protein [PMID:16304441 "Amelotin protein was efficiently secreted from transfected cells in culture."] of the basal lamina between maturation-stage ameloblasts and enamel [PMID:16787391 "immunofluorescence localization within the rat and mouse mandibles revealed Amtn localized to the basal lamina of maturation stage ameloblasts of incisors and unerupted molars."].

Summary: Basement membrane, combined automated annotation. Accepted.

Reason: AMTN is a secreted protein [PMID:16304441 "Amelotin protein was efficiently secreted from transfected cells in culture."] of the basal lamina between maturation-stage ameloblasts and enamel [PMID:16787391 "immunofluorescence localization within the rat and mouse mandibles revealed Amtn localized to the basal lamina of maturation stage ameloblasts of incisors and unerupted molars."].

Summary: Basement membrane, by similarity to rat. Accepted.

Reason: AMTN is a secreted protein [PMID:16304441 "Amelotin protein was efficiently secreted from transfected cells in culture."] of the basal lamina between maturation-stage ameloblasts and enamel [PMID:16787391 "immunofluorescence localization within the rat and mouse mandibles revealed Amtn localized to the basal lamina of maturation stage ameloblasts of incisors and unerupted molars."].

Summary: Endoplasmic reticulum lumen, from a Reactome reaction modelling post-translational processing of secreted proteins. A transit compartment; kept as non-core.

Reason: AMTN is secreted and post-translationally modified on the way [PMID:16787391 "Transient transfection experiments in HEK-293 cells (human embryonic kidney cells) showed that secreted Amtn is post-translationally modified possibly through O-linked oligosaccharides on threonine residues."]; the ER lumen is a transit location, not where it acts.

Summary: Cell-cell junction, inherited from rodent annotations that rest on localization to the junctional epithelium's basal lamina. A tissue-name conflation; marked as over-annotated.

Reason: The source annotation comes from rodent immunolocalization to the internal basal lamina of the junctional epithelium [PMID:16787391 "Intense Amtn protein expression was also detected in the internal basal lamina of junctional epithelium in molars."]. The junctional epithelium is the gingival tissue that attaches to the tooth; the basal lamina it forms against the enamel is an extracellular matrix, not a junction between cells. GO:0005911 cell-cell junction is a connection between cells, so the annotation conflates the tissue's name with the cellular component. Recombinant AMTN does not even mediate cell attachment [PMID:21912076 "Recombinant AMTN protein did not mediate cell attachment in vitro."], and the dentogingival attachment is intact in Amtn-null mice [PMID:25715379 "The integrity of the dentogingival attachment at the junctional epithelium appeared unaffected by AMTN deficiency."]. AMTN's location there is captured by the basement membrane and extracellular matrix rows. The rodent IDA rests on an abstract-only record, so the source is flagged rather than overruled.

Summary: Cell-cell junction, combined automated annotation from the rodent orthologs. Same conflation; marked as over-annotated.

Reason: The source annotation comes from rodent immunolocalization to the internal basal lamina of the junctional epithelium [PMID:16787391 "Intense Amtn protein expression was also detected in the internal basal lamina of junctional epithelium in molars."]. The junctional epithelium is the gingival tissue that attaches to the tooth; the basal lamina it forms against the enamel is an extracellular matrix, not a junction between cells. GO:0005911 cell-cell junction is a connection between cells, so the annotation conflates the tissue's name with the cellular component. Recombinant AMTN does not even mediate cell attachment [PMID:21912076 "Recombinant AMTN protein did not mediate cell attachment in vitro."], and the dentogingival attachment is intact in Amtn-null mice [PMID:25715379 "The integrity of the dentogingival attachment at the junctional epithelium appeared unaffected by AMTN deficiency."]. AMTN's location there is captured by the basement membrane and extracellular matrix rows. The rodent IDA rests on an abstract-only record, so the source is flagged rather than overruled.

Summary: Cell-cell junction, by similarity to rat. Same conflation; marked as over-annotated.

Reason: The source annotation comes from rodent immunolocalization to the internal basal lamina of the junctional epithelium [PMID:16787391 "Intense Amtn protein expression was also detected in the internal basal lamina of junctional epithelium in molars."]. The junctional epithelium is the gingival tissue that attaches to the tooth; the basal lamina it forms against the enamel is an extracellular matrix, not a junction between cells. GO:0005911 cell-cell junction is a connection between cells, so the annotation conflates the tissue's name with the cellular component. Recombinant AMTN does not even mediate cell attachment [PMID:21912076 "Recombinant AMTN protein did not mediate cell attachment in vitro."], and the dentogingival attachment is intact in Amtn-null mice [PMID:25715379 "The integrity of the dentogingival attachment at the junctional epithelium appeared unaffected by AMTN deficiency."]. AMTN's location there is captured by the basement membrane and extracellular matrix rows. The rodent IDA rests on an abstract-only record, so the source is flagged rather than overruled.

Summary: Extracellular matrix, combined automated annotation. Accepted.

Reason: AMTN is a secreted protein [PMID:16304441 "Amelotin protein was efficiently secreted from transfected cells in culture."] of the basal lamina between maturation-stage ameloblasts and enamel [PMID:16787391 "immunofluorescence localization within the rat and mouse mandibles revealed Amtn localized to the basal lamina of maturation stage ameloblasts of incisors and unerupted molars."].

Summary: Extracellular matrix, by similarity to mouse. Accepted.

Reason: AMTN is a secreted protein [PMID:16304441 "Amelotin protein was efficiently secreted from transfected cells in culture."] of the basal lamina between maturation-stage ameloblasts and enamel [PMID:16787391 "immunofluorescence localization within the rat and mouse mandibles revealed Amtn localized to the basal lamina of maturation stage ameloblasts of incisors and unerupted molars."].

Summary: Extracellular matrix, by similarity to rat. Accepted.

Reason: AMTN is a secreted protein [PMID:16304441 "Amelotin protein was efficiently secreted from transfected cells in culture."] of the basal lamina between maturation-stage ameloblasts and enamel [PMID:16787391 "immunofluorescence localization within the rat and mouse mandibles revealed Amtn localized to the basal lamina of maturation stage ameloblasts of incisors and unerupted molars."].

Summary: Odontogenesis of dentin-containing tooth, inherited through the PANTHER node. A correct, broad parent context for its enamel role; accepted.

Reason: Recombinant human AMTN binds hydroxyapatite [PMID:25407797 "The binding affinity of rh-AMTN to HA was found to be comparable to that of amelogenin, the major protein of the forming enamel matrix."] and promotes its precipitation, through a phosphorylatable SSEEL motif [PMID:25407797 "Site-specific mutagenesis of the potential serine phosphorylation motif SSEEL reduced the in vitro mineral precipitation to less than 25%, revealing that this motif is important for the HA mineralizing function of the protein."]; it directly influences biomineralization [PMID:25407797 "These findings demonstrate that AMTN has a direct influence on biomineralization by promoting HA mineralization"]. In vivo, Amtn-null mice have defective surface enamel [PMID:25715379 "These observations indicate that AMTN plays a subtle yet critical role in enamel biomineralization, particularly during the establishment of the outer and surface enamel layers."], and a human AMTN deletion lowers enamel mineral density [PMID:27412008 "Exfoliated primary teeth from an affected family member had enamel that was of a lower mineral density compared to control enamel"]. AMTN is a secreted protein [PMID:16304441 "Amelotin protein was efficiently secreted from transfected cells in culture."] of the basal lamina between maturation-stage ameloblasts and enamel [PMID:16787391 "immunofluorescence localization within the rat and mouse mandibles revealed Amtn localized to the basal lamina of maturation stage ameloblasts of incisors and unerupted molars."].

Summary: Odontogenesis of dentin-containing tooth, combined automated annotation. Accepted.

Reason: Recombinant human AMTN binds hydroxyapatite [PMID:25407797 "The binding affinity of rh-AMTN to HA was found to be comparable to that of amelogenin, the major protein of the forming enamel matrix."] and promotes its precipitation, through a phosphorylatable SSEEL motif [PMID:25407797 "Site-specific mutagenesis of the potential serine phosphorylation motif SSEEL reduced the in vitro mineral precipitation to less than 25%, revealing that this motif is important for the HA mineralizing function of the protein."]; it directly influences biomineralization [PMID:25407797 "These findings demonstrate that AMTN has a direct influence on biomineralization by promoting HA mineralization"]. In vivo, Amtn-null mice have defective surface enamel [PMID:25715379 "These observations indicate that AMTN plays a subtle yet critical role in enamel biomineralization, particularly during the establishment of the outer and surface enamel layers."], and a human AMTN deletion lowers enamel mineral density [PMID:27412008 "Exfoliated primary teeth from an affected family member had enamel that was of a lower mineral density compared to control enamel"].

Summary: Odontogenesis of dentin-containing tooth, by similarity to mouse; AMTN is ameloblast-specific. Accepted.

Reason: [PMID:16304441 "Expression of amelotin mRNA was restricted to maturation-stage ameloblasts in developing murine molars and incisors."] Recombinant human AMTN binds hydroxyapatite [PMID:25407797 "The binding affinity of rh-AMTN to HA was found to be comparable to that of amelogenin, the major protein of the forming enamel matrix."] and promotes its precipitation, through a phosphorylatable SSEEL motif [PMID:25407797 "Site-specific mutagenesis of the potential serine phosphorylation motif SSEEL reduced the in vitro mineral precipitation to less than 25%, revealing that this motif is important for the HA mineralizing function of the protein."]; it directly influences biomineralization [PMID:25407797 "These findings demonstrate that AMTN has a direct influence on biomineralization by promoting HA mineralization"]. In vivo, Amtn-null mice have defective surface enamel [PMID:25715379 "These observations indicate that AMTN plays a subtle yet critical role in enamel biomineralization, particularly during the establishment of the outer and surface enamel layers."], and a human AMTN deletion lowers enamel mineral density [PMID:27412008 "Exfoliated primary teeth from an affected family member had enamel that was of a lower mineral density compared to control enamel"].

Summary: Positive regulation of biomineral tissue development: recombinant AMTN promotes hydroxyapatite mineralization. Accepted.

Reason: Recombinant human AMTN binds hydroxyapatite [PMID:25407797 "The binding affinity of rh-AMTN to HA was found to be comparable to that of amelogenin, the major protein of the forming enamel matrix."] and promotes its precipitation, through a phosphorylatable SSEEL motif [PMID:25407797 "Site-specific mutagenesis of the potential serine phosphorylation motif SSEEL reduced the in vitro mineral precipitation to less than 25%, revealing that this motif is important for the HA mineralizing function of the protein."]; it directly influences biomineralization [PMID:25407797 "These findings demonstrate that AMTN has a direct influence on biomineralization by promoting HA mineralization"]. In vivo, Amtn-null mice have defective surface enamel [PMID:25715379 "These observations indicate that AMTN plays a subtle yet critical role in enamel biomineralization, particularly during the establishment of the outer and surface enamel layers."], and a human AMTN deletion lowers enamel mineral density [PMID:27412008 "Exfoliated primary teeth from an affected family member had enamel that was of a lower mineral density compared to control enamel"].

Summary: Positive regulation of enamel mineralization, inherited through the PANTHER node. AMTN promotes hydroxyapatite formation in maturation-stage enamel; core, accepted.

Reason: Recombinant human AMTN binds hydroxyapatite [PMID:25407797 "The binding affinity of rh-AMTN to HA was found to be comparable to that of amelogenin, the major protein of the forming enamel matrix."] and promotes its precipitation, through a phosphorylatable SSEEL motif [PMID:25407797 "Site-specific mutagenesis of the potential serine phosphorylation motif SSEEL reduced the in vitro mineral precipitation to less than 25%, revealing that this motif is important for the HA mineralizing function of the protein."]; it directly influences biomineralization [PMID:25407797 "These findings demonstrate that AMTN has a direct influence on biomineralization by promoting HA mineralization"]. In vivo, Amtn-null mice have defective surface enamel [PMID:25715379 "These observations indicate that AMTN plays a subtle yet critical role in enamel biomineralization, particularly during the establishment of the outer and surface enamel layers."], and a human AMTN deletion lowers enamel mineral density [PMID:27412008 "Exfoliated primary teeth from an affected family member had enamel that was of a lower mineral density compared to control enamel"].

Summary: Positive regulation of enamel mineralization, combined automated annotation. Accepted.

Reason: Recombinant human AMTN binds hydroxyapatite [PMID:25407797 "The binding affinity of rh-AMTN to HA was found to be comparable to that of amelogenin, the major protein of the forming enamel matrix."] and promotes its precipitation, through a phosphorylatable SSEEL motif [PMID:25407797 "Site-specific mutagenesis of the potential serine phosphorylation motif SSEEL reduced the in vitro mineral precipitation to less than 25%, revealing that this motif is important for the HA mineralizing function of the protein."]; it directly influences biomineralization [PMID:25407797 "These findings demonstrate that AMTN has a direct influence on biomineralization by promoting HA mineralization"]. In vivo, Amtn-null mice have defective surface enamel [PMID:25715379 "These observations indicate that AMTN plays a subtle yet critical role in enamel biomineralization, particularly during the establishment of the outer and surface enamel layers."], and a human AMTN deletion lowers enamel mineral density [PMID:27412008 "Exfoliated primary teeth from an affected family member had enamel that was of a lower mineral density compared to control enamel"].

Summary: Hydroxyapatite binding: recombinant human AMTN binds HA crystals with an affinity comparable to amelogenin. Not represented in GOA.

Reason: Recombinant human AMTN binds hydroxyapatite [PMID:25407797 "The binding affinity of rh-AMTN to HA was found to be comparable to that of amelogenin, the major protein of the forming enamel matrix."] and promotes its precipitation, through a phosphorylatable SSEEL motif [PMID:25407797 "Site-specific mutagenesis of the potential serine phosphorylation motif SSEEL reduced the in vitro mineral precipitation to less than 25%, revealing that this motif is important for the HA mineralizing function of the protein."]; it directly influences biomineralization [PMID:25407797 "These findings demonstrate that AMTN has a direct influence on biomineralization by promoting HA mineralization"]. In vivo, Amtn-null mice have defective surface enamel [PMID:25715379 "These observations indicate that AMTN plays a subtle yet critical role in enamel biomineralization, particularly during the establishment of the outer and surface enamel layers."], and a human AMTN deletion lowers enamel mineral density [PMID:27412008 "Exfoliated primary teeth from an affected family member had enamel that was of a lower mineral density compared to control enamel"]. The binding is shown directly, by immunogold labelling on the crystals [PMID:25407797 "Colloidal gold immunolabeling of AMTN in the mineral deposits showed that protein molecules were associated with HA crystals."] and affinity measurement. Participation: AMTN's own protein surface binds the mineral; this is the molecular activity behind its accepted mineralization rows. Comparator: AMELX, the enamel protein AMTN is benchmarked against, carries GO:0046848 (by ISS and IEA in QuickGO). Other mineralized-matrix proteins (DMP1, SPP1, ENAM, ODAM) lack it, which here reflects missing curation rather than a convention against the term, since its definition is exactly the binding measured. It is not an ancestor or descendant of any term the gene carries.