SKA1
entrez
220134
canonical
uniprot
Q96BD8
canonical
ensembl
ENSG00000154839
resolver
ensembl
ENSG00000262634
resolver
ensp
ENSP00000285116
resolver
ensp
ENSP00000381470
resolver
genesymbol
SKA1
resolver
genesymbol_syn
C18orf24
resolver
hgnc
HGNC:28109
resolver
uniprot
B2R9Y6
resolver
uniprot
B4E0P4
resolver
uniprot_entry
SKA1_HUMAN
resolver
uniprot_sec
B2R9Y6
resolver
uniprot_sec
B4E0P4
resolver
amino_acid_sequence
MASSDLEQLCSHVNEKIGNIKKTLSLRNCGQEPTLKTVLNKIGDEIIVINELLNKLELEIQYQEQTNNSLKELCESLEEDYKDIEHLKENVPSHLPQVTVTQSCVKGSDLDPEEPIKVEEPEPVKKPPKEQRSIKEMPFITCDEFNGVPSYMKSRLTYNQINDVIKEINKAVISKYKILHQPKKSMNSVTRNLYHRFIDEETKDTKGRYFIVEADIKEFTTLKADKKFHVLLNILRHCRRLSEVRGGGLTRYVIT
uniprot
proteins
function
FUNCTION: Component of the SKA complex, a microtubule plus end-binding complex of the outer kinetochore that stabilizes spindle microtubule-kinetochore attachments, promotes alignment of chromosomes at the mitotic spindle equator (chromosome congression) and assists suppression of the spindle assembly checkpoint (PubMed:17093495, PubMed:19289083, PubMed:22371557, PubMed:22483620, PubMed:23085020, PubMed:26981768, PubMed:27697923, PubMed:29487209, PubMed:31804178). Kinetochores, consisting of a centromere-associated inner segment and a microtubule-contacting outer segment, play a crucial role in chromosome segregation by mediating the physical connection between centromeric DNA and spindle microtubules (PubMed:19289083, PubMed:22483620, PubMed:23085020, PubMed:28479321, PubMed:29487209). The outer kinetochore is made up of the ten-subunit KMN network complex, comprising the MIS12, NDC80 and KNL1 complexes, and auxiliary microtubule-associated components such as the SKA complex; together they connect the outer kinetochore with the inner kinetochore, bind microtubules, and mediate interactions with mitotic checkpoint proteins that delay anaphase until chromosomes are bioriented on the spindle (PubMed:17093495, PubMed:19289083, PubMed:23085020, PubMed:28479321, PubMed:29487209). The SKA complex is loaded onto bioriented kinetochores and it facilitates chromosome congression by stabilizing microtubules together with MAPRE1, and end-on attachment of the NDC80 complex to depolymerizing spindle microtubules, thereby assisting the poleward-moving kinetochore in withstanding microtubule pulling forces (PubMed:19289083, PubMed:22371557, PubMed:22454517, PubMed:23085020, PubMed:24413531, PubMed:27697923, PubMed:28479321, PubMed:28495837, PubMed:29487209). The complex associates with dynamic microtubule plus-ends and can track both depolymerizing and elongating microtubules (PubMed:23085020, PubMed:29153323). The complex recruits protein phosphatase 1 (PP1) to the kinetochore in prometaphase and metaphase, to oppose spindle assembly checkpoint signaling and promote the onset of anaphase (PubMed:26981768). In the complex, it mediates interactions with microtubules (PubMed:19289083, PubMed:22483620, PubMed:23085020, PubMed:24413531, PubMed:27667719, PubMed:29153323, PubMed:36592928). It also stimulates AURKB/Aurora B catalytic activity (PubMed:27697923). During meiosis the SKA complex stabilizes the meiotic spindle and is required for its migration to the cortex (By similarity). {ECO:0000250|UniProtKB:Q9CPV1, ECO:0000269|PubMed:17093495, ECO:0000269|PubMed:19289083, ECO:0000269|PubMed:22371557, ECO:0000269|PubMed:22454517, ECO:0000269|PubMed:22483620, ECO:0000269|PubMed:23085020, ECO:0000269|PubMed:24413531, ECO:0000269|PubMed:26981768, ECO:0000269|PubMed:27667719, ECO:0000269|PubMed:27697923, ECO:0000269|PubMed:28479321, ECO:0000269|PubMed:28495837, ECO:0000269|PubMed:29153323, ECO:0000269|PubMed:29487209, ECO:0000269|PubMed:31804178, ECO:0000269|PubMed:36592928}.
uniprot
proteins
mass_dalton
29484
uniprot
proteins
mutagenesis
MUTAGEN 95..96; /note="LP->NN: Abolishes binding to MAPRE1."; /evidence="ECO:0000269|PubMed:36592928"; MUTAGEN 155; /note="R->A: Decreases microtubule binding; when associated with A-236 and A-245."; /evidence="ECO:0000269|PubMed:23085020, ECO:0000269|PubMed:24413531"; MUTAGEN 183..184; /note="KK->AA: Decreases microtubule binding; when associated with 203-A--A-206."; /evidence="ECO:0000269|PubMed:24413531"; MUTAGEN 185; /note="S->D: Phosphomimetic mutant which strongly reduces microtubule binding; when associated with D-205 or D-242."; /evidence="ECO:0000269|PubMed:23085020, ECO:0000269|PubMed:24413531"; MUTAGEN 203..206; /note="KDTK->ADTA: Decreases microtubule binding; when associated with 183-A--A-184."; /evidence="ECO:0000269|PubMed:24413531"; MUTAGEN 205; /note="T->D: Phosphomimetic mutant which strongly reduces microtubule binding; when associated with D-185."; /evidence="ECO:0000269|PubMed:24413531"; MUTAGEN 217; /note="K->A: Decreases microtubule binding; when associated with 223-A--A-227."; /evidence="ECO:0000269|PubMed:24413531"; MUTAGEN 223..227; /note="KADKK->AADAA: Decreases microtubule binding; when associated with A-217."; /evidence="ECO:0000269|PubMed:24413531"; MUTAGEN 236; /note="R->A: Decreases microtubule binding; when associated with A-155 and A-245."; /evidence="ECO:0000269|PubMed:23085020, ECO:0000269|PubMed:24413531"; MUTAGEN 242; /note="S->D: Phosphomimetic mutant which strongly reduces microtubule binding; when associated with D-185."; /evidence="ECO:0000269|PubMed:23085020"; MUTAGEN 245; /note="R->A: Decreases microtubule binding; when associated with A-155 and A-236."; /evidence="ECO:0000269|PubMed:23085020, ECO:0000269|PubMed:24413531
uniprot
proteins
post_translational_modification
PTM: Phosphorylated by AURKB at Thr-157 and Ser-242 which negatively regulates the association of the SKA complex with kinetochores to allow correction of aberrant kinetochore-microtubule interactions and promote mitotic sister chromatid biorientation. {ECO:0000269|PubMed:22371557}.
uniprot
proteins
protein_family
SKA1 family
uniprot
proteins
pubmed
14702039
uniprot
proteins
pubmed
15489334
uniprot
proteins
pubmed
15561729
uniprot
proteins
pubmed
17093495
uniprot
proteins
pubmed
19289083
uniprot
proteins
pubmed
19387489
uniprot
proteins
pubmed
19413330
uniprot
proteins
pubmed
19646878
uniprot
proteins
pubmed
21269460
uniprot
proteins
pubmed
22371557
uniprot
proteins
pubmed
22454517
uniprot
proteins
pubmed
22483620
uniprot
proteins
pubmed
23085020
uniprot
proteins
pubmed
24413531
uniprot
proteins
pubmed
26981768
uniprot
proteins
pubmed
27225956
uniprot
proteins
pubmed
27667719
uniprot
proteins
pubmed
27697923
uniprot
proteins
pubmed
28441529
uniprot
proteins
pubmed
28479321
uniprot
proteins
pubmed
28495837
uniprot
proteins
pubmed
28535377
uniprot
proteins
pubmed
29153323
uniprot
proteins
pubmed
29487209
uniprot
proteins
pubmed
31804178
uniprot
proteins
pubmed
32491969
uniprot
proteins
pubmed
36592928
uniprot
proteins
sequence_length
255
uniprot
proteins
subcellular_location
SUBCELLULAR LOCATION: Cytoplasm, cytoskeleton, spindle {ECO:0000269|PubMed:15561729, ECO:0000269|PubMed:24413531, ECO:0000269|PubMed:26981768, ECO:0000269|PubMed:27225956, ECO:0000305|PubMed:29487209}. Chromosome, centromere, kinetochore {ECO:0000269|PubMed:17093495, ECO:0000269|PubMed:22483620, ECO:0000269|PubMed:24413531, ECO:0000269|PubMed:26981768, ECO:0000269|PubMed:28479321}. Cytoplasm, cytoskeleton, microtubule organizing center, centrosome {ECO:0000269|PubMed:19646878}. Note=Localizes to bioriented kinetochores and spindle microtubules during metaphase in a NDC80 complex-dependent manner (PubMed:17093495, PubMed:28479321, PubMed:29487209). The SKA complex begins to concentrate at kinetochores before microtubule attachment but reaches maximum levels on bioriented metaphase chromosomes (PubMed:17093495). Localizes both to microtubule plus-ends and along the length of microtubules (PubMed:27225956). The localization of the SKA complex to kinetochores is positively regulated by protein serine/threonine kinase CDK1 (PubMed:28479321). The localization of the SKA complex to kinetochores is negatively regulated by protein serine/threonine kinase AURKB, and this action is opposed directly or indirectly by the PP1 and PP2A protein phosphatase complexes (PubMed:22371557, PubMed:27697923). Localizes at the centrosome during interphase and prophase (PubMed:19646878). Localizes to the meiotic spindle, but not to kinetochores, from the stage of germinal vesicle breakdown (GVBD) to meiosis II (MII) (By similarity). {ECO:0000250|UniProtKB:Q9CPV1, ECO:0000269|PubMed:17093495, ECO:0000269|PubMed:19646878, ECO:0000269|PubMed:22371557, ECO:0000269|PubMed:27225956, ECO:0000269|PubMed:27697923, ECO:0000269|PubMed:28479321, ECO:0000269|PubMed:29487209}.
uniprot
proteins