Ki-67 (protein)

Antigen identified by monoclonal antibody Ki-67

PDB rendering based on 1r21.
Identifiers
Symbols MKI67; KIA; Ki-67
External IDs OMIM: 176741 MGI: 106035 HomoloGene: 1814 GeneCards: MKI67 Gene
Orthologs
Species Human Mouse
Entrez 4288 17345
Ensembl ENSG00000148773 ENSMUSG00000031004
UniProt P46013 Q7TSF6
RefSeq (mRNA) NM_001145966.1 NM_001081117.2
RefSeq (protein) NP_001139438.1 NP_001074586.2
Location (UCSC) Chr 10:
129.89 – 129.92 Mb		 Chr 7:
142.88 – 142.91 Mb
PubMed search [1] [2]

Antigen KI-67 also known as Ki-67 or MKI67 is a protein that in humans is encoded by the MKI67 gene (antigen identified by monoclonal antibody Ki-67).[1][2][3]

Contents

Function

Antigen KI-67 is a nuclear protein that is associated with and may be necessary for cellular proliferation. Furthermore it is associated with ribosomal RNA transcription.[3] Inactivation of antigen KI-67 leads to inhibition of ribosomal RNA synthesis.[4]

Use as cell marker

The Ki-67 protein (also known as MKI67) is a cellular marker for proliferation.[5] It is strictly associated with cell proliferation. During interphase, the Ki-67 antigen can be exclusively detected within the cell nucleus, whereas in mitosis most of the protein is relocated to the surface of the chromosomes. Ki-67 protein is present during all active phases of the cell cycle (G1, S, G2, and mitosis), but is absent from resting cells (G0).

Antibody labeling

Ki-67 is an excellent marker to determine the growth fraction of a given cell population. The fraction of Ki-67-positive tumor cells (the Ki-67 labeling index) is often correlated with the clinical course of cancer. The best-studied examples in this context are carcinomas of the prostate, brain and the breast. For these types of tumors, the prognostic value for survival and tumor recurrence have repeatedly been proven in uni- and multivariate analysis.

MIB-1

MIB1 is a commonly used monoclonal antibody that detects the Ki-67 antigen. It is used in clinical applications to determine the Ki-67 labelling index. One of its primary advantages over the original Ki-67 antibody (and the reason why it has essentially supplanted the original antibody for clinical use) is that it can be used on formalin-fixed paraffin-embedded sections, after heat-mediated antigen retrieval (see section Original Ki-67 antibody).

Original Ki-67 antibody

The Ki-67 protein was originally defined by the prototype monoclonal antibody Ki-67,[6] which was generated by immunizing mice with nuclei of the Hodgkin lymphoma cell line L428. The name is derived from the city of origin (Kiel, Germany) and the number of the original clone in the 96-well plate.

Interactions

Ki-67 (protein) has been shown to interact with CBX3.[7]

See also


Additional images

References

  1. ^ "Entrez Gene: Antigen identified by monoclonal antibody Ki-67". http://www.ncbi.nlm.nih.gov/sites/entrez?Db=gene&Cmd=ShowDetailView&TermToSearch=4288. 
  2. ^ Schonk DM, Kuijpers HJ, van Drunen E, van Dalen CH, Geurts van Kessel AH, Verheijen R, Ramaekers FC (October 1989). "Assignment of the gene(s) involved in the expression of the proliferation-related Ki-67 antigen to human chromosome 10". Hum. Genet. 83 (3): 297–9. doi:10.1007/BF00285178. PMID 2571566. 
  3. ^ a b Bullwinkel J, Baron-Lühr B, Lüdemann A, Wohlenberg C, Gerdes J, Scholzen T (March 2006). "Ki-67 protein is associated with ribosomal RNA transcription in quiescent and proliferating cells". J. Cell. Physiol. 206 (3): 624–35. doi:10.1002/jcp.20494. PMID 16206250. 
  4. ^ Rahmanzadeh R, Hüttmann G, Gerdes J, Scholzen T (June 2007). "Chromophore-assisted light inactivation of pKi-67 leads to inhibition of ribosomal RNA synthesis". Cell Prolif. 40 (3): 422–30. doi:10.1111/j.1365-2184.2007.00433.x. PMID 17531085. 
  5. ^ Scholzen T, Gerdes J (March 2000). "The Ki-67 protein: from the known and the unknown". J. Cell. Physiol. 182 (3): 311–22. doi:10.1002/(SICI)1097-4652(200003)182:3<311::AID-JCP1>3.0.CO;2-9. PMID 10653597. 
  6. ^ Gerdes J, Schwab U, Lemke H, Stein H (1983). "Production of a mouse monoclonal antibody reactive with a human nuclear antigen associated with cell proliferation". Int. J. Cancer 31 (1): 13–20. doi:10.1002/ijc.2910310104. PMID 6339421. http://www3.interscience.wiley.com/cgi-bin/abstract/112713361/. 
  7. ^ Kametaka, Ai; Takagi Masatoshi, Hayakawa Tomohiro, Haraguchi Tokuko, Hiraoka Yasushi, Yoneda Yoshihiro (Dec. 2002). "Interaction of the chromatin compaction-inducing domain (LR domain) of Ki-67 antigen with HP1 proteins". Genes Cells (England) 7 (12): 1231–42. doi:10.1046/j.1365-2443.2002.00596.x. ISSN 1356-9597. PMID 12485163. 

External links