Skip Header

You are using a version of browser that may not display all the features of this website. Please consider upgrading your browser.
Protein

Spindle and kinetochore-associated protein 1

Gene

SKA1

Organism
Homo sapiens (Human)
Status
Reviewed-Annotation score: Annotation score: 5 out of 5-Experimental evidence at protein leveli

Functioni

Component of the SKA1 complex, a microtubule-binding subcomplex of the outer kinetochore that is essential for proper chromosome segregation (PubMed:17093495, PubMed:19289083, PubMed:23085020). Required for timely anaphase onset during mitosis, when chromosomes undergo bipolar attachment on spindle microtubules leading to silencing of the spindle checkpoint (PubMed:17093495). The SKA1 complex is a direct component of the kinetochore-microtubule interface and directly associates with microtubules as oligomeric assemblies (PubMed:19289083). The complex facilitates the processive movement of microspheres along a microtubule in a depolymerization-coupled manner (PubMed:19289083). Affinity for microtubules is synergistically enhanced in the presence of the ndc-80 complex and may allow the ndc-80 complex to track depolymerizing microtubules (PubMed:23085020). In the complex, it mediates the interaction with microtubules (PubMed:19289083, PubMed:23085020).3 Publications

GO - Molecular functioni

  • microtubule binding Source: UniProtKB

GO - Biological processi

  • cell division Source: UniProtKB
  • chromosome segregation Source: UniProtKB
  • mitotic nuclear division Source: UniProtKB
  • regulation of microtubule polymerization or depolymerization Source: UniProtKB
  • sister chromatid cohesion Source: Reactome
Complete GO annotation...

Keywords - Biological processi

Cell cycle, Cell division, Mitosis

Enzyme and pathway databases

ReactomeiR-HSA-2467813. Separation of Sister Chromatids.
R-HSA-2500257. Resolution of Sister Chromatid Cohesion.
R-HSA-5663220. RHO GTPases Activate Formins.
R-HSA-68877. Mitotic Prometaphase.

Names & Taxonomyi

Protein namesi
Recommended name:
Spindle and kinetochore-associated protein 1
Gene namesi
Name:SKA1
Synonyms:C18orf24
OrganismiHomo sapiens (Human)
Taxonomic identifieri9606 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
Proteomesi
  • UP000005640 Componenti: Chromosome 18

Organism-specific databases

HGNCiHGNC:28109. SKA1.

Subcellular locationi

  • Cytoplasmcytoskeletonspindle 1 Publication
  • Chromosomecentromerekinetochore 1 Publication

  • Note: Localizes to the outer kinetochore and spindle microtubules during mitosis in a NDC80 complex-dependent manner (PubMed:17093495). Localizes to both the mitotic spindle and kinetochore-associated proteins (PubMed:17093495). Associates with kinetochores following microtubule attachment from prometaphase, through mid-anaphase and then vanishes in telophase (PubMed:17093495).1 Publication

GO - Cellular componenti

  • condensed chromosome outer kinetochore Source: UniProtKB
  • cytosol Source: Reactome
  • spindle microtubule Source: UniProtKB
Complete GO annotation...

Keywords - Cellular componenti

Centromere, Chromosome, Cytoplasm, Cytoskeleton, Kinetochore, Microtubule

Pathology & Biotechi

Mutagenesis

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Mutagenesisi155 – 1551R → A: Abolishes microtubule binding; when associated with A-236 and A-245. 1 Publication
Mutagenesisi185 – 1851S → D: Phosphomimetic mutant which strongly reduces microtubule binding; when associated with D-242. 1 Publication
Mutagenesisi236 – 2361R → A: Abolishes microtubule binding; when associated with A-155 and A-245. 1 Publication
Mutagenesisi242 – 2421S → D: Phosphomimetic mutant which strongly reduces microtubule binding; when associated with D-185. 1 Publication
Mutagenesisi245 – 2451R → A: Abolishes microtubule binding; when associated with A-155 and A-236. 1 Publication

Organism-specific databases

PharmGKBiPA165429102.

Polymorphism and mutation databases

BioMutaiSKA1.
DMDMi74731226.

PTM / Processingi

Molecule processing

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Initiator methionineiRemovedCombined sources
Chaini2 – 255254Spindle and kinetochore-associated protein 1PRO_0000273155Add
BLAST

Amino acid modifications

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Modified residuei2 – 21N-acetylalanineCombined sources

Keywords - PTMi

Acetylation

Proteomic databases

EPDiQ96BD8.
MaxQBiQ96BD8.
PaxDbiQ96BD8.
PRIDEiQ96BD8.

PTM databases

iPTMnetiQ96BD8.
PhosphoSiteiQ96BD8.

Expressioni

Gene expression databases

BgeeiQ96BD8.
CleanExiHS_C18orf24.
ExpressionAtlasiQ96BD8. baseline and differential.
GenevisibleiQ96BD8. HS.

Organism-specific databases

HPAiHPA045495.

Interactioni

Subunit structurei

Component of the SKA1 complex, composed of SKA1, SKA2 and SKA3 (PubMed:17093495). Forms a heterodimer with SKA2; the heterodimer interacting with SKA3 (PubMed:17093495, PubMed:19289083, PubMed:23085020). The core SKA1 complex is composed of 2 SKA1-SKA2 heterodimers, each heterodimer interacting with a molecule of the SKA3 homodimer (PubMed:19289083). The core SKA1 complex associates with microtubules and forms oligomeric assemblies (PubMed:17093495, PubMed:19289083). Interacts with microtubules; the interaction is direct (PubMed:19289083, PubMed:23085020). Interacts with SKA2 (PubMed:19289083). Interacts with SKA3 (PubMed:19289083, PubMed:23085020).3 Publications

Binary interactionsi

WithEntry#Exp.IntActNotes
BLOC1S6Q9UL454EBI-741854,EBI-465781
SKA2Q8WVK711EBI-741854,EBI-1773994
SYCE1Q8N0S23EBI-741854,EBI-6872807

GO - Molecular functioni

  • microtubule binding Source: UniProtKB

Protein-protein interaction databases

BioGridi128632. 45 interactions.
IntActiQ96BD8. 39 interactions.
MINTiMINT-2813709.
STRINGi9606.ENSP00000285116.

Structurei

Secondary structure

1
255
Legend: HelixTurnBeta strand
Show more details
Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Helixi5 – 3127Combined sources
Helixi33 – 7947Combined sources
Helixi82 – 887Combined sources
Helixi142 – 1465Combined sources
Helixi150 – 1534Combined sources
Helixi158 – 17922Combined sources
Helixi183 – 1853Combined sources
Helixi188 – 20013Combined sources
Turni203 – 2075Combined sources
Beta strandi210 – 2123Combined sources
Helixi213 – 2197Combined sources
Helixi226 – 23712Combined sources
Beta strandi240 – 2445Combined sources
Beta strandi251 – 2544Combined sources

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
4AJ5X-ray3.32A/B/C/D/E/F/G/H/I/J1-91[»]
4C9YX-ray2.01A/B133-255[»]
4CA0X-ray2.26A/B133-255[»]
ProteinModelPortaliQ96BD8.
SMRiQ96BD8. Positions 3-89, 133-255.
ModBaseiSearch...
MobiDBiSearch...

Family & Domainsi

Region

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Regioni132 – 255124Microtubule binding1 PublicationAdd
BLAST

Coiled coil

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Coiled coili49 – 9143Sequence analysisAdd
BLAST

Sequence similaritiesi

Belongs to the SKA1 family.Curated

Keywords - Domaini

Coiled coil

Phylogenomic databases

eggNOGiKOG4832. Eukaryota.
ENOG4111IBI. LUCA.
GeneTreeiENSGT00390000011654.
HOGENOMiHOG000154331.
HOVERGENiHBG082236.
InParanoidiQ96BD8.
OMAiDYKDVEH.
PhylomeDBiQ96BD8.
TreeFamiTF324442.

Family and domain databases

InterProiIPR009829. SKA1.
[Graphical view]
PANTHERiPTHR28573:SF1. PTHR28573:SF1. 1 hit.
PfamiPF07160. DUF1395. 1 hit.
[Graphical view]

Sequences (2)i

Sequence statusi: Complete.

Sequence processingi: The displayed sequence is further processed into a mature form.

This entry describes 2 isoformsi produced by alternative splicing. AlignAdd to basket

Isoform 1 (identifier: Q96BD8-1) [UniParc]FASTAAdd to basket

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.

« Hide

        10         20         30         40         50
MASSDLEQLC SHVNEKIGNI KKTLSLRNCG QEPTLKTVLN KIGDEIIVIN
60 70 80 90 100
ELLNKLELEI QYQEQTNNSL KELCESLEED YKDIEHLKEN VPSHLPQVTV
110 120 130 140 150
TQSCVKGSDL DPEEPIKVEE PEPVKKPPKE QRSIKEMPFI TCDEFNGVPS
160 170 180 190 200
YMKSRLTYNQ INDVIKEINK AVISKYKILH QPKKSMNSVT RNLYHRFIDE
210 220 230 240 250
ETKDTKGRYF IVEADIKEFT TLKADKKFHV LLNILRHCRR LSEVRGGGLT

RYVIT
Length:255
Mass (Da):29,484
Last modified:December 1, 2001 - v1
Checksum:i40F578B0B6D9B64D
GO
Isoform 2 (identifier: Q96BD8-2) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     104-150: CVKGSDLDPEEPIKVEEPEPVKKPPKEQRSIKEMPFITCDEFNGVPS → W

Note: No experimental confirmation available.
Show »
Length:209
Mass (Da):24,390
Checksum:i754BCEB9A8705B39
GO

Natural variant

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Natural varianti91 – 911V → I.1 Publication
Corresponds to variant rs6507992 [ dbSNP | Ensembl ].
VAR_030091

Alternative sequence

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Alternative sequencei104 – 15047CVKGS…NGVPS → W in isoform 2. 1 PublicationVSP_037250Add
BLAST

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AK303464 mRNA. Translation: BAG64506.1.
AK313968 mRNA. Translation: BAG36683.1.
CH471096 Genomic DNA. Translation: EAW62971.1.
BC015706 mRNA. Translation: AAH15706.1.
CCDSiCCDS11946.1. [Q96BD8-1]
RefSeqiNP_001034624.1. NM_001039535.2. [Q96BD8-1]
NP_659497.1. NM_145060.3. [Q96BD8-1]
UniGeneiHs.134726.

Genome annotation databases

EnsembliENST00000285116; ENSP00000285116; ENSG00000154839. [Q96BD8-1]
ENST00000398452; ENSP00000381470; ENSG00000154839. [Q96BD8-1]
ENST00000417656; ENSP00000397222; ENSG00000154839. [Q96BD8-2]
ENST00000571751; ENSP00000458992; ENSG00000262634. [Q96BD8-1]
ENST00000616604; ENSP00000478259; ENSG00000262634. [Q96BD8-1]
ENST00000633940; ENSP00000488815; ENSG00000262634. [Q96BD8-2]
GeneIDi220134.
KEGGihsa:220134.
UCSCiuc002let.4. human. [Q96BD8-1]

Keywords - Coding sequence diversityi

Alternative splicing, Polymorphism

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AK303464 mRNA. Translation: BAG64506.1.
AK313968 mRNA. Translation: BAG36683.1.
CH471096 Genomic DNA. Translation: EAW62971.1.
BC015706 mRNA. Translation: AAH15706.1.
CCDSiCCDS11946.1. [Q96BD8-1]
RefSeqiNP_001034624.1. NM_001039535.2. [Q96BD8-1]
NP_659497.1. NM_145060.3. [Q96BD8-1]
UniGeneiHs.134726.

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
4AJ5X-ray3.32A/B/C/D/E/F/G/H/I/J1-91[»]
4C9YX-ray2.01A/B133-255[»]
4CA0X-ray2.26A/B133-255[»]
ProteinModelPortaliQ96BD8.
SMRiQ96BD8. Positions 3-89, 133-255.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi128632. 45 interactions.
IntActiQ96BD8. 39 interactions.
MINTiMINT-2813709.
STRINGi9606.ENSP00000285116.

PTM databases

iPTMnetiQ96BD8.
PhosphoSiteiQ96BD8.

Polymorphism and mutation databases

BioMutaiSKA1.
DMDMi74731226.

Proteomic databases

EPDiQ96BD8.
MaxQBiQ96BD8.
PaxDbiQ96BD8.
PRIDEiQ96BD8.

Protocols and materials databases

DNASUi220134.
Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENST00000285116; ENSP00000285116; ENSG00000154839. [Q96BD8-1]
ENST00000398452; ENSP00000381470; ENSG00000154839. [Q96BD8-1]
ENST00000417656; ENSP00000397222; ENSG00000154839. [Q96BD8-2]
ENST00000571751; ENSP00000458992; ENSG00000262634. [Q96BD8-1]
ENST00000616604; ENSP00000478259; ENSG00000262634. [Q96BD8-1]
ENST00000633940; ENSP00000488815; ENSG00000262634. [Q96BD8-2]
GeneIDi220134.
KEGGihsa:220134.
UCSCiuc002let.4. human. [Q96BD8-1]

Organism-specific databases

CTDi220134.
GeneCardsiSKA1.
H-InvDBHIX0022882.
HGNCiHGNC:28109. SKA1.
HPAiHPA045495.
MIMi616673. gene.
neXtProtiNX_Q96BD8.
PharmGKBiPA165429102.
GenAtlasiSearch...

Phylogenomic databases

eggNOGiKOG4832. Eukaryota.
ENOG4111IBI. LUCA.
GeneTreeiENSGT00390000011654.
HOGENOMiHOG000154331.
HOVERGENiHBG082236.
InParanoidiQ96BD8.
OMAiDYKDVEH.
PhylomeDBiQ96BD8.
TreeFamiTF324442.

Enzyme and pathway databases

ReactomeiR-HSA-2467813. Separation of Sister Chromatids.
R-HSA-2500257. Resolution of Sister Chromatid Cohesion.
R-HSA-5663220. RHO GTPases Activate Formins.
R-HSA-68877. Mitotic Prometaphase.

Miscellaneous databases

ChiTaRSiSKA1. human.
GenomeRNAii220134.
PROiQ96BD8.
SOURCEiSearch...

Gene expression databases

BgeeiQ96BD8.
CleanExiHS_C18orf24.
ExpressionAtlasiQ96BD8. baseline and differential.
GenevisibleiQ96BD8. HS.

Family and domain databases

InterProiIPR009829. SKA1.
[Graphical view]
PANTHERiPTHR28573:SF1. PTHR28573:SF1. 1 hit.
PfamiPF07160. DUF1395. 1 hit.
[Graphical view]
ProtoNetiSearch...

Publicationsi

« Hide 'large scale' publications
  1. "Complete sequencing and characterization of 21,243 full-length human cDNAs."
    Ota T., Suzuki Y., Nishikawa T., Otsuki T., Sugiyama T., Irie R., Wakamatsu A., Hayashi K., Sato H., Nagai K., Kimura K., Makita H., Sekine M., Obayashi M., Nishi T., Shibahara T., Tanaka T., Ishii S.
    , Yamamoto J., Saito K., Kawai Y., Isono Y., Nakamura Y., Nagahari K., Murakami K., Yasuda T., Iwayanagi T., Wagatsuma M., Shiratori A., Sudo H., Hosoiri T., Kaku Y., Kodaira H., Kondo H., Sugawara M., Takahashi M., Kanda K., Yokoi T., Furuya T., Kikkawa E., Omura Y., Abe K., Kamihara K., Katsuta N., Sato K., Tanikawa M., Yamazaki M., Ninomiya K., Ishibashi T., Yamashita H., Murakawa K., Fujimori K., Tanai H., Kimata M., Watanabe M., Hiraoka S., Chiba Y., Ishida S., Ono Y., Takiguchi S., Watanabe S., Yosida M., Hotuta T., Kusano J., Kanehori K., Takahashi-Fujii A., Hara H., Tanase T.-O., Nomura Y., Togiya S., Komai F., Hara R., Takeuchi K., Arita M., Imose N., Musashino K., Yuuki H., Oshima A., Sasaki N., Aotsuka S., Yoshikawa Y., Matsunawa H., Ichihara T., Shiohata N., Sano S., Moriya S., Momiyama H., Satoh N., Takami S., Terashima Y., Suzuki O., Nakagawa S., Senoh A., Mizoguchi H., Goto Y., Shimizu F., Wakebe H., Hishigaki H., Watanabe T., Sugiyama A., Takemoto M., Kawakami B., Yamazaki M., Watanabe K., Kumagai A., Itakura S., Fukuzumi Y., Fujimori Y., Komiyama M., Tashiro H., Tanigami A., Fujiwara T., Ono T., Yamada K., Fujii Y., Ozaki K., Hirao M., Ohmori Y., Kawabata A., Hikiji T., Kobatake N., Inagaki H., Ikema Y., Okamoto S., Okitani R., Kawakami T., Noguchi S., Itoh T., Shigeta K., Senba T., Matsumura K., Nakajima Y., Mizuno T., Morinaga M., Sasaki M., Togashi T., Oyama M., Hata H., Watanabe M., Komatsu T., Mizushima-Sugano J., Satoh T., Shirai Y., Takahashi Y., Nakagawa K., Okumura K., Nagase T., Nomura N., Kikuchi H., Masuho Y., Yamashita R., Nakai K., Yada T., Nakamura Y., Ohara O., Isogai T., Sugano S.
    Nat. Genet. 36:40-45(2004) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORMS 1 AND 2), VARIANT ILE-91.
    Tissue: Thymus.
  2. Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
  3. "The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC)."
    The MGC Project Team
    Genome Res. 14:2121-2127(2004) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 1).
    Tissue: Uterus.
  4. Cited for: SUBCELLULAR LOCATION, IDENTIFICATION BY MASS SPECTROMETRY.
  5. "Timely anaphase onset requires a novel spindle and kinetochore complex comprising Ska1 and Ska2."
    Hanisch A., Sillje H.H.W., Nigg E.A.
    EMBO J. 25:5504-5515(2006) [PubMed] [Europe PMC] [Abstract]
    Cited for: FUNCTION, SUBCELLULAR LOCATION, INTERACTION WITH SKA2.
  6. "Lys-N and trypsin cover complementary parts of the phosphoproteome in a refined SCX-based approach."
    Gauci S., Helbig A.O., Slijper M., Krijgsveld J., Heck A.J., Mohammed S.
    Anal. Chem. 81:4493-4501(2009) [PubMed] [Europe PMC] [Abstract]
    Cited for: ACETYLATION [LARGE SCALE ANALYSIS] AT ALA-2, CLEAVAGE OF INITIATOR METHIONINE [LARGE SCALE ANALYSIS], IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
  7. "The human kinetochore Ska1 complex facilitates microtubule depolymerization-coupled motility."
    Welburn J.P.I., Grishchuk E.L., Backer C.B., Wilson-Kubalek E.M., Yates J.R. III, Cheeseman I.M.
    Dev. Cell 16:374-385(2009) [PubMed] [Europe PMC] [Abstract]
    Cited for: FUNCTION, SUBCELLULAR LOCATION, IDENTIFICATION IN THE SKA1 COMPLEX, INTERACTION WITH MICROTUBULES; SKA2 AND SKA3.
  8. Cited for: IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
  9. "The kinetochore-bound Ska1 complex tracks depolymerizing microtubules and binds to curved protofilaments."
    Schmidt J.C., Arthanari H., Boeszoermenyi A., Dashkevich N.M., Wilson-Kubalek E.M., Monnier N., Markus M., Oberer M., Milligan R.A., Bathe M., Wagner G., Grishchuk E.L., Cheeseman I.M.
    Dev. Cell 23:968-980(2012) [PubMed] [Europe PMC] [Abstract]
    Cited for: FUNCTION, INTERACTION WITH SKA3 AND MICROTUBULES, MUTAGENESIS OF ARG-155; SER-185; ARG-236; SER-242 AND ARG-245.

Entry informationi

Entry nameiSKA1_HUMAN
AccessioniPrimary (citable) accession number: Q96BD8
Secondary accession number(s): B2R9Y6, B4E0P4
Entry historyi
Integrated into UniProtKB/Swiss-Prot: January 23, 2007
Last sequence update: December 1, 2001
Last modified: June 8, 2016
This is version 107 of the entry and version 1 of the sequence. [Complete history]
Entry statusiReviewed (UniProtKB/Swiss-Prot)
Annotation programChordata Protein Annotation Program
DisclaimerAny medical or genetic information present in this entry is provided for research, educational and informational purposes only. It is not in any way intended to be used as a substitute for professional medical advice, diagnosis, treatment or care.

Miscellaneousi

Keywords - Technical termi

3D-structure, Complete proteome, Reference proteome

Documents

  1. Human chromosome 18
    Human chromosome 18: entries, gene names and cross-references to MIM
  2. Human entries with polymorphisms or disease mutations
    List of human entries with polymorphisms or disease mutations
  3. Human polymorphisms and disease mutations
    Index of human polymorphisms and disease mutations
  4. MIM cross-references
    Online Mendelian Inheritance in Man (MIM) cross-references in UniProtKB/Swiss-Prot
  5. PDB cross-references
    Index of Protein Data Bank (PDB) cross-references
  6. SIMILARITY comments
    Index of protein domains and families

Similar proteinsi

Links to similar proteins from the UniProt Reference Clusters (UniRef) at 100%, 90% and 50% sequence identity:
100%UniRef100 combines identical sequences and sub-fragments with 11 or more residues from any organism into one UniRef entry.
90%UniRef90 is built by clustering UniRef100 sequences that have at least 90% sequence identity to, and 80% overlap with, the longest sequence (a.k.a seed sequence).
50%UniRef50 is built by clustering UniRef90 seed sequences that have at least 50% sequence identity to, and 80% overlap with, the longest sequence in the cluster.