KIF22 — Kinesin Family Member 22
Overview <table class="infobox infobox-gene">
Gene Structure and Evolution The KIF22 gene spans approximately 25 kb on chromosome 16p11.2 and consists of 20 exons. It encodes a protein of 805 amino acids, also known as KIDIN (Kinesin Family Member Involved in Development). KIF22 belongs to the kinesin-7 family, which includes the well-characterized centromere-associated protein E (CENP-E/KIF10).
KIF22 is conserved among vertebrates and evolved from the kinesin-7 family that acquired specialized functions in chromosome dynamics and development.
Protein Structure and Biochemistry KIF22 has key structural features:
Motor Domain Architecture ...
KIF22 — Kinesin Family Member 22
Overview <table class="infobox infobox-gene">
Gene Structure and Evolution The KIF22 gene spans approximately 25 kb on chromosome 16p11.2 and consists of 20 exons. It encodes a protein of 805 amino acids, also known as KIDIN (Kinesin Family Member Involved in Development). KIF22 belongs to the kinesin-7 family, which includes the well-characterized centromere-associated protein E (CENP-E/KIF10).
KIF22 is conserved among vertebrates and evolved from the kinesin-7 family that acquired specialized functions in chromosome dynamics and development.
Protein Structure and Biochemistry KIF22 has key structural features:
Motor Domain Architecture
N-terminal motor domain (1-350 aa) : ATP-binding site and microtubule interaction regionCoiled-coil region (350-600 aa) : Dimerization and cargo bindingC-terminal tail (600-805 aa) : Regulatory domain controlling localizationBiochemical Properties
Processive movement : Can walk along microtubulesPlus-end directionality : Moves toward microtubule plus endsChromosome binding : Can bind to chromosomes during mitosis
Post-translational Modifications
Phosphorylation : Sites regulated during cell cycleAcetylation : Affects motor functionNormal Cellular Function
Chromosome Dynamics KIF22 plays essential roles in mitosis:
Chromosome congression : Helps move chromosomes to the metaphase plateSpindle assembly : Contributes to mitotic spindle formationChromosome segregation : Aids in proper chromosome separationResearch demonstrates that KIF22 is required for proper chromosome alignment and segregation during mitosis [@yi2019].
Mitotic Checkpoint KIF22 contributes to mitotic checkpoint function:
Spindle assembly checkpoint : Helps ensure proper chromosome attachmentCheckpoint signaling : Participates in checkpoint protein recruitmentAnaphase onset : Regulates transition to anaphase
Skeletal Development KIF22 has important functions in bone development:
Chondrocyte function : Regulates cartilage cell developmentBone formation : Contributes to endochondral ossificationGrowth plate organization : Essential for proper skeletal growthThis developmental function explains why KIF22 mutations cause skeletal dysplasias.
Role in Disease
KIF22 mutations cause SEMD, a skeletal disorder:
Short stature : Reduced growthSkeletal abnormalities : Abnormal bone developmentJoint problems : Early-onset osteoarthritisMutations in KIF22 disrupt both its mitotic function and its role in skeletal development [@hussein2019].
Cancer KIF22 expression is altered in some cancers:
Dysregulation : Altered expression in certain malignanciesChromosome instability : Contributes to aneuploidyTherapeutic target : Potential for cancer treatment
Neurodegeneration Connections While not directly linked to AD or PD:
Cell cycle re-entry : Relevant to neuronal dysfunctionChromosome dynamics : May affect neuronal developmentDevelopmental origins : Early skeletal development may influence later vulnerability
Protein-Protein Interactions
Chromosome-associated Proteins
CENP-E : Related kinesin in chromosome movementKinetochore proteins : Localize to kinetochores during mitosisMitotic Regulators
Aurora kinases : Cell cycle regulationBubR1 : Spindle assembly checkpointDevelopmental Proteins
SOX9 : Chondrogenesis regulatorCollagens : Extracellular matrix proteinsClinical Significance
Genetic Disorders
SEMD : Autosomal dominant inheritanceSkeletal malformations : Spectrum of severityDiagnostic Applications
Genetic testing : Identifies pathogenic variantsPrenatal diagnosis : Possible for families with mutationsTherapeutic Implications
Skeletal disorders : Understanding KIF22 function may inform treatmentsCancer therapy : Targeting mitotic kinesinsRegenerative medicine : Bone development applications
Research Directions
Developmental mechanisms : Elucidating KIF22's role in skeletogenesisTherapeutic targeting : Developing KIF22-modulating compoundsDisease models : Characterizing KIF22 mutations
See Also
[Axonal Transport](/mechanisms/axonal-transport)
[Kinesin Family](/proteins/kinesin-family)
[Cell Division](/mechanisms/cell-division)
[Skeletal Development](/mechanisms/skeletal-development)
[Alzheimer's Disease](/diseases/alzheimers-disease)
External Links
[NCBI Gene: KIF22](https://www.ncbi.nlm.nih.gov/gene/11176)
[UniProt: Q9NRL3](https://www.uniprot.org/uniprot/Q9NRL3)
[Ensembl: ENSG00000125967](https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000125967)
References
[NCBI Gene: KIF22 (n.d.)](https://www.ncbi.nlm.nih.gov/gene/11176)
[Yi et al., KIF22 in chromosome congression and segregation (2019)](https://pubmed.ncbi.nlm.nih.gov/31166267/)
[Hussein et al., KIF22 mutations cause spondyloepimetaphyseal dysplasia (2019)](https://pubmed.ncbi.nlm.nih.gov/30655565/)
Show full description