Q9Y448 · SKAP_HUMAN
- ProteinSmall kinetochore-associated protein
- GeneKNSTRN
- StatusUniProtKB reviewed (Swiss-Prot)
- Organism
- Amino acids316 (go to sequence)
- Protein existenceEvidence at protein level
- Annotation score5/5
Function
function
Essential component of the mitotic spindle required for faithful chromosome segregation and progression into anaphase (PubMed:19667759).
Promotes the metaphase-to-anaphase transition and is required for chromosome alignment, normal timing of sister chromatid segregation, and maintenance of spindle pole architecture (PubMed:19667759, PubMed:22110139).
The astrin (SPAG5)-kinastrin (SKAP) complex promotes stable microtubule-kinetochore attachments (PubMed:21402792).
Required for kinetochore oscillations and dynamics of microtubule plus-ends during live cell mitosis, possibly by forming a link between spindle microtubule plus-ends and mitotic chromosomes to achieve faithful cell division (PubMed:23035123).
May be involved in UV-induced apoptosis via its interaction with PRPF19; however, these results need additional evidences (PubMed:24718257).
Promotes the metaphase-to-anaphase transition and is required for chromosome alignment, normal timing of sister chromatid segregation, and maintenance of spindle pole architecture (PubMed:19667759, PubMed:22110139).
The astrin (SPAG5)-kinastrin (SKAP) complex promotes stable microtubule-kinetochore attachments (PubMed:21402792).
Required for kinetochore oscillations and dynamics of microtubule plus-ends during live cell mitosis, possibly by forming a link between spindle microtubule plus-ends and mitotic chromosomes to achieve faithful cell division (PubMed:23035123).
May be involved in UV-induced apoptosis via its interaction with PRPF19; however, these results need additional evidences (PubMed:24718257).
GO annotations
all annotations | all molecular function | virus receptor activity | dna binding | rna binding | cytoskeletal motor activity | catalytic activity | gtpase activity | structural molecule activity | transporter activity | cytoskeletal protein binding | lipid binding | cyclase activity | antioxidant activity | oxidoreductase activity | transferase activity | hydrolase activity | lyase activity | isomerase activity | ligase activity | protein tag activity | cargo receptor activity | histone binding | protein folding chaperone | translation regulator activity | nutrient reservoir activity | receptor ligand activity | molecular transducer activity | molecular adaptor activity | toxin activity | cell adhesion mediator activity | molecular function regulator activity | virus coreceptor activity | catalytic activity, acting on a protein | catalytic activity, acting on dna | catalytic activity, acting on rna | molecular carrier activity | transcription regulator activity | general transcription initiation factor activity | molecular sensor activity | molecular sequestering activity | atp-dependent activity | other molecular function | all biological process | mitotic cell cycle | cytokinesis | cytoplasmic translation | immune system process | muscle system process | circulatory system process | renal system process | respiratory system process | carbohydrate metabolic process | generation of precursor metabolites and energy | dna replication | dna repair | dna recombination | chromatin organization | dna-templated transcription | regulation of dna-templated transcription | trna metabolic process | protein folding | protein glycosylation | amino acid metabolic process | modified amino acid metabolic process | lipid metabolic process | vitamin metabolic process | sulfur compound metabolic process | intracellular protein transport | nucleocytoplasmic transport | autophagy | inflammatory response | mitochondrion organization | cytoskeleton organization | microtubule-based movement | peroxisome organization | lysosome organization | chromosome segregation | cell adhesion | establishment or maintenance of cell polarity | programmed cell death | photosynthesis | mrna metabolic process | snrna metabolic process | vesicle-mediated transport | reproductive process | digestive system process | signaling | cell differentiation | protein catabolic process | extracellular matrix organization | regulatory ncrna-mediated gene silencing | telomere organization | cell junction organization | wound healing | ribosome biogenesis | cilium organization | anatomical structure development | cell motility | nervous system process | endocrine process | protein maturation | transmembrane transport | nucleobase-containing small molecule metabolic process | hepaticobiliary system process | membrane organization | protein-containing complex assembly | cell wall organization or biogenesis | nitrogen cycle metabolic process | protein localization to plasma membrane | defense response to other organism | detoxification | meiotic nuclear division | mitotic nuclear division | mitochondrial gene expression | carbohydrate derivative metabolic process | other biological process | all cellular component | nuclear chromosome | extracellular region | extracellular space | cell wall | nucleus | nuclear envelope | nucleoplasm | chromosome | nucleolus | mitochondrion | lysosome | endosome | vacuole | peroxisome | endoplasmic reticulum | golgi apparatus | lipid droplet | microtubule organizing center | cytosol | ribosome | cytoskeleton | plasma membrane | cilium | plastid | thylakoid | external encapsulating structure | extracellular matrix | cytoplasmic vesicle | organelle | other cellular component | |||
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Aspect | Term | |
---|---|---|
Cellular Component | centriolar satellite | |
Cellular Component | cytoplasm | |
Cellular Component | kinetochore | |
Cellular Component | microtubule organizing center | |
Cellular Component | microtubule plus-end | |
Cellular Component | mitotic spindle | |
Cellular Component | nucleus | |
Cellular Component | plasma membrane | |
Cellular Component | ruffle | |
Cellular Component | spindle pole | |
Molecular Function | microtubule plus-end binding | |
Molecular Function | protein homodimerization activity | |
Biological Process | cell division | |
Biological Process | cell migration | |
Biological Process | cellular response to epidermal growth factor stimulus | |
Biological Process | chromosome segregation | |
Biological Process | microtubule cytoskeleton organization | |
Biological Process | mitotic sister chromatid segregation | |
Biological Process | regulation of attachment of spindle microtubules to kinetochore | |
Biological Process | spindle organization |
Keywords
- Biological process
Enzyme and pathway databases
Interacts with EB1 during early but not late mitosis.
Names & Taxonomy
Protein names
- Recommended nameSmall kinetochore-associated protein
- Short namesSKAP
- Alternative names
Gene names
- Community suggested namesSKAP
Organism names
- Organism
- Taxonomic lineageEukaryota > Metazoa > Chordata > Craniata > Vertebrata > Euteleostomi > Mammalia > Eutheria > Euarchontoglires > Primates > Haplorrhini > Catarrhini > Hominidae > Homo
Accessions
- Primary accessionQ9Y448
- Secondary accessions
Proteomes
Organism-specific databases
Subcellular Location
UniProt Annotation
GO Annotation
Note: Colocalizes with microtubules around centrosomes in prophase and with the mitotic spindle at prometaphase and metaphase. From late prometaphase to anaphase, is highly concentrated on kinetochores. Located at the kinetochore-microtubule interface. The astrin (SPAG5)-kinastrin (SKAP) complex localizes to the microtubule plus ends (PubMed:23035123).
Keywords
- Cellular component
Disease & Variants
Involvement in disease
Roifman-Chitayat syndrome (ROCHIS)
- Note
- DescriptionAn autosomal recessive digenic disorder characterized by global developmental delay, variable neurologic features such as seizures and ataxia, optic atrophy, dysmorphic facial features, distal skeletal anomalies, and recurrent invasive infections due to combined immunodeficiency.
- See alsoMIM:613328
Features
Showing features for natural variant.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Natural variant | VAR_071857 | 24 | in SCC; impaired chromatid cohesion; dbSNP:rs868438023 | |||
Sequence: S → F | ||||||
Natural variant | VAR_030304 | 40 | in dbSNP:rs7164132 | |||
Sequence: A → E | ||||||
Natural variant | VAR_030305 | 75 | in dbSNP:rs7169404 | |||
Sequence: R → L | ||||||
Natural variant | VAR_030306 | 92 | in dbSNP:rs7169262 | |||
Sequence: P → S |
Variants
We now provide the "Disease & Variants" viewer in its own tab.
The viewer provides 414 variants from UniProt as well as other sources including ClinVar and dbSNP.
Keywords
- Disease
Organism-specific databases
Miscellaneous
Genetic variation databases
PTM/Processing
Features
Showing features for chain, modified residue, modified residue (large scale data).
Type | ID | Position(s) | Source | Description | |||
---|---|---|---|---|---|---|---|
Chain | PRO_0000274512 | 1-316 | UniProt | Small kinetochore-associated protein | |||
Sequence: MAAPEAPPLDRVFRTTWLSTECDSHPLPPSYRKFLFETQAADLAGGTTVAAGNLLNESEKDCGQDRRAPGVQPCRLVTMTSVVKTVYSLQPPSALSGGQPADTQTRATSKSLLPVRSKEVDVSKQLHSGGPENDVTKITKLRRENGQMKATDTATRRNVRKGYKPLSKQKSEEELKDKNQLLEAVNKQLHQKLTETQGELKDLTQKVELLEKFRDNCLAILESKGLDPALGSETLASRQESTTDHMDSMLLLETLQEELKLFNETAKKQMEELQALKVKLEMKEERVRFLEQQTLCNNQVNDLTTALKEMEQLLEM | |||||||
Modified residue | 128 | UniProt | Phosphoserine | ||||
Sequence: S | |||||||
Modified residue (large scale data) | 128 | PRIDE | Phosphoserine | ||||
Sequence: S | |||||||
Modified residue (large scale data) | 171 | PRIDE | Phosphoserine | ||||
Sequence: S |
Keywords
- PTM
Proteomic databases
PTM databases
Expression
Tissue specificity
Widely expressed, including in skin.
Induction
Degraded at the end of mitosis. Down-regulated upon exposure to nitric oxide.
Gene expression databases
Organism-specific databases
Interaction
Subunit
Part of an astrin (SPAG5)-kinastrin (SKAP) complex containing KNSTRN, SPAG5, PLK1, DYNLL1 and SGO2 (PubMed:21402792).
Interacts with SPAG5 (PubMed:21402792).
Directly binds to microtubules, although at relatively low affinity (PubMed:21402792).
Interacts with CENPE; this interaction greatly favors microtubule-binding (PubMed:22110139).
Interacts with DSN1/MIS13; leading to localization to kinetochores (PubMed:23035123).
Interacts with MAPRE1/EB1; leading to localization to the microtubule plus ends (PubMed:23035123).
Interacts with PRPF19 (PubMed:24718257).
Interacts with DYNLL1 (PubMed:22965910).
Interacts with MAP4 (PubMed:29180244).
Interacts with SPAG5 (PubMed:21402792).
Directly binds to microtubules, although at relatively low affinity (PubMed:21402792).
Interacts with CENPE; this interaction greatly favors microtubule-binding (PubMed:22110139).
Interacts with DSN1/MIS13; leading to localization to kinetochores (PubMed:23035123).
Interacts with MAPRE1/EB1; leading to localization to the microtubule plus ends (PubMed:23035123).
Interacts with PRPF19 (PubMed:24718257).
Interacts with DYNLL1 (PubMed:22965910).
Interacts with MAP4 (PubMed:29180244).
Binary interactions
Type | Entry 1 | Entry 2 | Number of experiments | Intact | |
---|---|---|---|---|---|
BINARY | Q9Y448 | ABI2 Q9NYB9-2 | 3 | EBI-373334, EBI-11096309 | |
BINARY | Q9Y448 | BEX2 Q9BXY8 | 3 | EBI-373334, EBI-745073 | |
BINARY | Q9Y448 | HTT P42858 | 3 | EBI-373334, EBI-466029 | |
BINARY | Q9Y448 | IFT20 Q8IY31-3 | 3 | EBI-373334, EBI-9091197 | |
BINARY | Q9Y448 | MAPRE1 Q15691 | 5 | EBI-373334, EBI-1004115 | |
BINARY | Q9Y448 | MAPRE3 Q9UPY8 | 3 | EBI-373334, EBI-726739 | |
BINARY | Q9Y448 | OIP5 O43482 | 3 | EBI-373334, EBI-536879 | |
BINARY | Q9Y448 | PPL O60437 | 3 | EBI-373334, EBI-368321 | |
BINARY | Q9Y448 | SGF29 Q96ES7 | 8 | EBI-373334, EBI-743117 | |
BINARY | Q9Y448 | WASHC3 Q9Y3C0 | 6 | EBI-373334, EBI-712969 |
Protein-protein interaction databases
Miscellaneous
Structure
Family & Domains
Features
Showing features for region, coiled coil.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Region | 159-316 | Interaction with SPAG5 | ||||
Sequence: VRKGYKPLSKQKSEEELKDKNQLLEAVNKQLHQKLTETQGELKDLTQKVELLEKFRDNCLAILESKGLDPALGSETLASRQESTTDHMDSMLLLETLQEELKLFNETAKKQMEELQALKVKLEMKEERVRFLEQQTLCNNQVNDLTTALKEMEQLLEM | ||||||
Coiled coil | 166-216 | |||||
Sequence: LSKQKSEEELKDKNQLLEAVNKQLHQKLTETQGELKDLTQKVELLEKFRDN | ||||||
Coiled coil | 248-316 | |||||
Sequence: SMLLLETLQEELKLFNETAKKQMEELQALKVKLEMKEERVRFLEQQTLCNNQVNDLTTALKEMEQLLEM |
Domain
The coiled coil regions mediate binding to kinetochores.
Keywords
- Domain
Phylogenomic databases
Family and domain databases
Sequence & Isoforms
- Sequence statusComplete
This entry describes 3 isoforms produced by Alternative splicing.
Q9Y448-1
This isoform has been chosen as the canonical sequence. All positional information in this entry refers to it. This is also the sequence that appears in the downloadable versions of the entry.
- Name1
- Length316
- Mass (Da)35,438
- Last updated2007-02-06 v2
- Checksum6FC6745DBA6B70D8
Q9Y448-2
- Name2
- Differences from canonical
- 275-316: ALKVKLEMKEERVRFLEQQTLCNNQVNDLTTALKEMEQLLEM → IAWMNHGILHQM
Q9Y448-3
- Name3
- Differences from canonical
- 229-316: ALGSETLASRQESTTDHMDSMLLLETLQEELKLFNETAKKQMEELQALKVKLEMKEERVRFLEQQTLCNNQVNDLTTALKEMEQLLEM → VAVRNFARGAEAF
Computationally mapped potential isoform sequences
There are 8 potential isoforms mapped to this entry
Sequence caution
Features
Showing features for sequence conflict, alternative sequence.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Sequence conflict | 47 | in Ref. 4; AAH45739 | ||||
Sequence: T → K | ||||||
Alternative sequence | VSP_041069 | 229-316 | in isoform 3 | |||
Sequence: ALGSETLASRQESTTDHMDSMLLLETLQEELKLFNETAKKQMEELQALKVKLEMKEERVRFLEQQTLCNNQVNDLTTALKEMEQLLEM → VAVRNFARGAEAF | ||||||
Sequence conflict | 232 | in Ref. 4; AAI18640 | ||||
Sequence: S → G | ||||||
Sequence conflict | 236 | in Ref. 6; AAD24201 | ||||
Sequence: A → S | ||||||
Alternative sequence | VSP_041070 | 275-316 | in isoform 2 | |||
Sequence: ALKVKLEMKEERVRFLEQQTLCNNQVNDLTTALKEMEQLLEM → IAWMNHGILHQM |
Keywords
- Coding sequence diversity
- Technical term
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
AY652615 EMBL· GenBank· DDBJ | AAT66172.1 EMBL· GenBank· DDBJ | mRNA | ||
AK301887 EMBL· GenBank· DDBJ | BAG63319.1 EMBL· GenBank· DDBJ | mRNA | ||
AC013356 EMBL· GenBank· DDBJ | - | Genomic DNA | No translation available. | |
BC004543 EMBL· GenBank· DDBJ | AAH04543.1 EMBL· GenBank· DDBJ | mRNA | Different termination. | |
BC014060 EMBL· GenBank· DDBJ | AAH14060.1 EMBL· GenBank· DDBJ | mRNA | Different termination. | |
BC045739 EMBL· GenBank· DDBJ | AAH45739.1 EMBL· GenBank· DDBJ | mRNA | ||
BC064344 EMBL· GenBank· DDBJ | AAH64344.1 EMBL· GenBank· DDBJ | mRNA | ||
BC107802 EMBL· GenBank· DDBJ | AAI07803.1 EMBL· GenBank· DDBJ | mRNA | Different initiation | |
BC118559 EMBL· GenBank· DDBJ | AAI18560.1 EMBL· GenBank· DDBJ | mRNA | ||
BC118639 EMBL· GenBank· DDBJ | AAI18640.1 EMBL· GenBank· DDBJ | mRNA | ||
CR602848 EMBL· GenBank· DDBJ | - | mRNA | No translation available. | |
CR611451 EMBL· GenBank· DDBJ | - | mRNA | No translation available. | |
U81002 EMBL· GenBank· DDBJ | AAD24201.1 EMBL· GenBank· DDBJ | mRNA |