Atlas of Genetics and Cytogenetics in Oncology and Haematology
K-RAS (Kirsten rat sarcoma 2 viral oncogene homolog)
| Identity |
| Other names | c-Ki-ras 2 |
| HGNC (Hugo) | KRAS |
| Location | 12p12 |
| Location_base_pair | Starts at 25249447 and ends at 25295121 bp from pter ( according to hg18-Mar_2006) [Mapping] |
| Note | more on the RAS family is available as a deep insight |
| DNA/RNA |
 | |
| K-ras splicing variants alternative splicing of K-ras precursor mRNA leads to the two transcripts which differ by the ex- or inclusion of Exon 4a; Exons that encode protein are shown as black boxes, untranslated exons as white boxes; the upstream untranslated exon is indicated as Exon -1 | |
| Description | consists of six exons, spread over 35kb of genomic DNA. |
| Transcription | alternative RNA splicing reveals two different transcripts of 5.5 and 3.8kb (see Fig); if Exon 4a is skipped exon 4b is directly joined to exon 3; in 98% of the transcripts exon 4a is spliced out and only exon 4b is available for translation into protein. |
| Pseudogene | c-Ki-ras 1, inactivated, processed pseudogene which is located on Chromosome 6 |
| Protein |
| Description | regular RAS protein - characterized in the RAS family page. |
| Expression | ubiquitously expressed |
| Localisation | anchored to the inner surface of the plasma membrane |
| Function | analogously to other GTP-binding proteins (such as Translation Elongation Factor EFTu or signal transducing G-Proteins) RAS proteins are involved in signal transduction pathways |
| Homology | ras gene family is part of the ras superfamily including the mammalian RAS, RAL, RAC, RHO, RAP, and RAB gene families and the yeast homologs like SEC4 and YPT1 genes; genes encode small monomeric proteins of low molecular mass (20-30 kDa) which share at least 30% homology to RAS proteins. |
| Implicated in |
| Entity | tumor (frequency of K-RAS mutations); references in Full Bibliography |
| Entity | pancreas (80-90%) |
| Entity | colon and rectum (25-60%) |
| Entity | lung (25-60%) |
| Entity | prostate (0-25%) |
| Entity | skin (0-25%) |
| Entity | thyroid (0-60%) |
| Entity | liver (10-25%) |
| Entity | ovary (0-50%) |
| Entity | endometrium (10-40%) |
| Entity | kidney (0-50%) |
| Entity | brain (0-15%) |
| Entity | testis (seminoma) (10-45%) |
| Entity | acute non lymphocytic leukemia and myelodysplasia (5-15%) |
| Entity | urinary bladder (5%) |
| Entity | head and neck (10%) |
| Entity | breast (10%) |
| External links |
| Bibliography |
| Human cancer and cellular oncogenes. |
| Nishimura S, Sekiya T |
| The Biochemical journal. 1987 ; 243 (2) : 313-327. |
| PMID 3307760 |
| ras oncogenes in human cancer: a review. |
| Bos JL |
| Cancer research. 1989 ; 49 (17) : 4682-4689. |
| PMID 2547513 |
| ras oncogenes: their role in neoplasia. |
| Barbacid M |
| European journal of clinical investigation. 1990 ; 20 (3) : 225-235. |
| PMID 2114981 |
| ras activation in experimental carcinogenesis. |
| Mangues R, Pellicer A |
| Seminars in cancer biology. 1992 ; 3 (4) : 229-239. |
| PMID 1421167 |
| REVIEW articles | automatic search in PubMed |
| Last year publications | automatic search in PubMed |
| Contributor(s) |
| Written | 02-1999 | Franz Watzinger and Thomas Lion |
| Citation |
| This paper should be referenced as such : |
| Watzinger F and Lion T . K-RAS (Kirsten rat sarcoma 2 viral oncogene homolog). Atlas Genet Cytogenet Oncol Haematol. February 1999 . URL : http://AtlasGeneticsOncology.org/Genes/KRASID91.html |
| © Atlas of Genetics and Cytogenetics in Oncology and Haematology | indexed on : Sat Jun 27 16:42:13 CEST 2009 |
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