HUS1

Checkpoint protein HUS1 is a protein that in humans is encoded by the HUS1 gene.^[5][6]

HUS1
Available structures PDB Ortholog search: PDBe RCSB List of PDB id codes 3A1J, 3G65, 3GGR
Identifiers
Aliases	HUS1, hHUS1 checkpoint clamp component
External IDs	OMIM: 603760; MGI: 1277962; HomoloGene: 37932; GeneCards: HUS1; OMA:HUS1 - orthologs
Gene location (Human) Chr. Chromosome 7 (human)[1] Band 7p12.3 Start 47,963,288 bp[1] End 47,979,615 bp[1]
Gene location (Mouse) Chr. Chromosome 11 (mouse)[2] Band 11 A1|11 5.74 cM Start 8,943,137 bp[2] End 8,961,191 bp[2]
RNA expression pattern Bgee Human Mouse (ortholog) Top expressed in gonad monocyte sural nerve Achilles tendon islet of Langerhans rectum epithelium of colon muscle of thigh gastrocnemius muscle stromal cell of endometrium Top expressed in secondary oocyte primary oocyte zygote tail of embryo genital tubercle primitive streak substantia nigra proximal tubule ureter abdominal wall More reference expression data BioGPS More reference expression data
Gene ontology Molecular function protein binding Cellular component site of double-strand break cytoplasm cytosol nucleoplasm checkpoint clamp complex nucleolus nucleus Biological process regulation of protein phosphorylation nucleotide-excision repair meiotic DNA integrity checkpoint signaling embryo development mitotic cell cycle checkpoint signaling mitotic intra-S DNA damage checkpoint signaling negative regulation of DNA replication cellular response to DNA damage stimulus protein phosphorylation mitotic DNA replication checkpoint signaling cellular response to ionizing radiation response to UV double-strand break repair via homologous recombination DNA damage checkpoint signaling DNA repair embryo development ending in birth or egg hatching telomere maintenance DNA replication regulation of signal transduction by p53 class mediator Sources:Amigo / QuickGO
Orthologs Species Human Mouse Entrez 3364 15574 Ensembl ENSG00000136273 ENSMUSG00000020413 UniProt O60921 Q8BQY8 RefSeq (mRNA) NM_004507 NM_001363683 NM_008316 NM_001303532 NM_001303610 RefSeq (protein) NP_004498 NP_001350612 NP_001290461 NP_001290539 NP_032342 Location (UCSC) Chr 7: 47.96 – 47.98 Mb Chr 11: 8.94 – 8.96 Mb PubMed search [3] [4]
Wikidata
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Function

The protein encoded by this gene is a component of an evolutionarily conserved, genotoxin-activated checkpoint complex that is involved in the cell cycle arrest in response to DNA damage. This protein forms a heterotrimeric complex with checkpoint proteins RAD9 and RAD1. In response to DNA damage, the trimeric complex interacts with another protein complex consisting of checkpoint protein RAD17 and four small subunits of the replication factor C (RFC), which loads the combined complex onto the chromatin. The DNA damage induced chromatin binding has been shown to depend on the activation of the checkpoint kinase ATM, and is thought to be an early checkpoint signaling event.^[7]

In somatic cells

In somatic cells the RAD9-RAD1-HUS1 (9-1-1) complex responds to DNA damage by promoting DNA repair.^[8]

In meiosis

In flies, worms and yeast, the 9-1-1 complex is necessary for meiotic checkpoint function and efficient meiotic recombination.^[8] During mammalian meiosis 9-1-1 complexes promote synapsis of homologous chromosomes, double-strand break repair and cell cycle checkpoint signalling.^[8][9]

Interactions

HUS1 has been shown to interact with:

• HDAC1,^[10]
• PCNA,^[11]
• RAD1 homolog^[12][13]
• RAD17,^[14][15] and
• RAD9A.^{[16][12][17][18]}