Kinesin-associated protein 3

Kinesin-associated protein 3 (KAP3) is a protein that in humans is encoded by the KIFAP3 gene.^[5][6] It is a non-motor, accessory subunit which co-oligomerizes with the motor subunits KIF3A and KIF3B or KIF3C, to form heterotrimeric kinesin-2 motor proteins. Kinesin-2 KAP subunits were initially characterized in echinoderms and mice.^[7][8]

KIFAP3
Identifiers
Aliases	KIFAP3, FLA3, KAP-1, KAP-3, KAP3, SMAP, Smg-GDS, dJ190I16.1, kinesin associated protein 3
External IDs	OMIM: 601836; MGI: 107566; HomoloGene: 7799; GeneCards: KIFAP3; OMA:KIFAP3 - orthologs
Gene location (Human) Chr. Chromosome 1 (human)[1] Band 1q24.2 Start 169,921,326 bp[1] End 170,085,208 bp[1]
Gene location (Mouse) Chr. Chromosome 1 (mouse)[2] Band 1|1 H2.1 Start 163,607,152 bp[2] End 163,744,678 bp[2]
RNA expression pattern Bgee Human Mouse (ortholog) Top expressed in pons orbitofrontal cortex lateral nuclear group of thalamus Brodmann area 46 frontal pole postcentral gyrus prefrontal cortex ganglionic eminence sperm dorsolateral prefrontal cortex Top expressed in barrel cortex facial motor nucleus nucleus accumbens prefrontal cortex subiculum pontine nuclei temporal lobe medial dorsal nucleus anterior horn of spinal cord superior colliculus More reference expression data BioGPS More reference expression data
Gene ontology Molecular function protein binding kinesin binding intraciliary transport particle B binding protein phosphatase binding Cellular component intraciliary transport particle ciliary basal body cytosol centrosome Golgi apparatus kinesin complex microtubule cytoskeleton kinesin II complex photoreceptor connecting cilium condensed nuclear chromosome ciliary tip spindle microtubule endoplasmic reticulum periciliary membrane compartment axoneme cilium Biological process protein localization plus-end-directed vesicle transport along microtubule antigen processing and presentation of exogenous peptide antigen via MHC class II negative regulation of apoptotic process microtubule-based movement positive regulation of calcium-dependent cell-cell adhesion microtubule-based process signal transduction negative regulation of cell population proliferation retrograde vesicle-mediated transport, Golgi to endoplasmic reticulum intraciliary transport involved in cilium assembly protein-containing complex assembly Sources:Amigo / QuickGO
Orthologs Species Human Mouse Entrez 22920 16579 Ensembl ENSG00000075945 ENSMUSG00000026585 UniProt Q92845 P70188 RefSeq (mRNA) NM_001204514 NM_001204516 NM_001204517 NM_014970 NM_001375830 NM_001375831 NM_010629 NM_001305643 RefSeq (protein) NP_001191443 NP_001191445 NP_001191446 NP_055785 NP_001362759 NP_001362760 NP_001292572 NP_034759 Location (UCSC) Chr 1: 169.92 – 170.09 Mb Chr 1: 163.61 – 163.74 Mb PubMed search [3] [4]
Wikidata
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Function

The small G protein GDP dissociation stimulator (smg GDS) is a regulator protein having two activities on a group of small G proteins including the Rho and Rap1 family members and Ki-Ras; one is to stimulate their GDP/GTP exchange reactions, and the other is to inhibit their interactions with membranes. The protein encoded by this gene contains 9 Armadillo repeats and interacts with the smg GDS protein through these repeats. This protein, which is highly concentrated around the endoplasmic reticulum, is phosphorylated by v-src, and this phosphorylation reduces the affinity of the protein for smg GDS. It is thought that this protein serves as a linker between human chromosome-associated polypeptide (HCAP) and KIF3A/B, a kinesin superfamily protein in the nucleus, and that it plays a role in the interaction of chromosomes with an ATPase motor protein.^[6] It has also been proposed to act as a clamp, stabilizing the C-terminal half ^[9] of the otherwise unstable stalk coiled-coil.

Interactions

KIFAP3 has been shown to interact with APC,^[10] SMC3^[11] and RAP1GDS1.^[5]