The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.

wikigene or wiki gene protein drug chemical gene disease author authorship tracking collaborative publishing evolutionary knowledge reputation system wiki2.0 global collaboration genes proteins drugs chemicals diseases compound
Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)



Gene Review

XRN1  -  5'-3' exoribonuclease 1

Homo sapiens

Synonyms: SEP1, Strand-exchange protein 1 homolog
Welcome! If you are familiar with the subject of this article, you can contribute to this open access knowledge base by deleting incorrect information, restructuring or completely rewriting any text. Read more.

Disease relevance of XRN1

  • In the current study, we cloned a human SEP1 gene as a GDNF-inducible gene using human neuroblastoma cells that express RET and GFRalpha1 [1].
  • We show loss or reduced expression of hSEP1 messenger RNA (mRNA) in three of four primary osteogenic sarcoma (OGS)-derived cell lines and in eight of nine OGS biopsy specimen [2].
  • A mutation in the RNase MRP RNA confers Li+ hypersensitivity and is synthetically lethal with mutations in either HAL2 or XRN1 [3].
  • Both SEP1 and SEP2 were predictive of later cerebral palsy (CP) (p = 0.03 and p = 0.003, respectively) [4].
  • SEP1 and SEP2 were less accurate than head ultrasound findings of periventricular leukomalacia in the prediction of later CP (73, 69 and 93%, respectively) [4].

High impact information on XRN1

  • mRNA decay: x (XRN1) marks the spot [5].
  • In this pathway, splice-defective lariat intermediates are debranched by Dbr1p and subsequently degraded 5' to 3' primarily by the cytoplasmic exonuclease, Xrn1p [6].
  • In that Xrn1p and Ski2p are cytoplasmic and Dbr1p localizes to both the nucleus and the cytoplasm, these data suggest that this decay pathway occurs within the cytoplasm [6].
  • They are also dispersed by inhibitors of translational elongation and share several protein components, including Fas-activated serine/threonine phosphoprotein, XRN1, eIF4E, and tristetraprolin (TTP) [7].
  • The induction of the SEP1 gene showed two peaks at 0.5-2 h and 24-48 h after GDNF stimulation by Northern blotting and quantitative real-time reverse transcriptase polymerase chain reaction [1].

Biological context of XRN1

  • Taken together, these results suggest that hSEP1 acts as a tumor suppressor gene in OGS [2].
  • The hSEP1 gene is located in chromosome 3 at 3q25-26.1 between markers D3S1309 and D3S1569 [2].
  • The homozygous mutation in the hSEP1 mRNA in TE85 cell line suggest that this gene itself is subject to LOH [2].
  • Importantly, we identified a homozygous missense mutation involving a CG-dinucleotide leading to a change in a conserved amino acid, aspartic acid(1137) >asparagine, in the primary OGS-derived cell line, TE85. hSEP1 mRNA expression was nearly undetectable in TE85 and low in U2OS cell lines [2].
  • Yeast SEP1 is a multifunctional gene that regulates a variety of nuclear and cytoplasmic functions including homologous recombination, meiosis, telomere maintenance, RNA metabolism and microtubule assembly [2].

Anatomical context of XRN1

  • Identification of human SEP1 as a glial cell line-derived neurotrophic factor-inducible protein and its expression in the nervous system [1].
  • In addition, we found a high level of SEP1 expression in neurons of the dorsal root and superior cervical ganglia and motor neurons of the spinal cord of mice in which RET is also expressed [1].
  • Immunostaining revealed that the expression of the SEP1 protein was detected in cell body, elongated neurites and growth cone-like structure of neuroblastoma cells treated with GDNF [1].
  • Northern blot analysis showed a major 10-kb mRNA expressed ubiquitously in various organs as well as a minor 5.5-kb mRNA expressed relatively highly in the testis and placenta. hSEP1p is localized in the cytoplasm as examined by cytochemical and Western blot analyses of fractionated cellular extracts [8].
  • We recorded unilateral, median nerve SEPs in 88 preterm infants twice in the first 3 weeks of life (SEP1 and SEP2) [4].

Analytical, diagnostic and therapeutic context of XRN1


  1. Identification of human SEP1 as a glial cell line-derived neurotrophic factor-inducible protein and its expression in the nervous system. Shimoyama, Y., Morikawa, Y., Ichihara, M., Kodama, Y., Fukuda, N., Hayashi, H., Morinaga, T., Iwashita, T., Murakumo, Y., Takahashi, M. Neuroscience (2003) [Pubmed]
  2. The human homolog of yeast SEP1 is a novel candidate tumor suppressor gene in osteogenic sarcoma. Zhang, K., Dion, N., Fuchs, B., Damron, T., Gitelis, S., Irwin, R., O'Connor, M., Schwartz, H., Scully, S.P., Rock, M.G., Bolander, M.E., Sarkar, G. Gene (2002) [Pubmed]
  3. Lithium toxicity in yeast is due to the inhibition of RNA processing enzymes. Dichtl, B., Stevens, A., Tollervey, D. EMBO J. (1997) [Pubmed]
  4. Early somatosensory evoked potentials in preterm infants: their prognostic utility. Ekert, P.G., Taylor, M.J., Keenan, N.K., Boulton, J.E., Whyte, H.E. Biol. Neonate (1997) [Pubmed]
  5. mRNA decay: x (XRN1) marks the spot. Long, R.M., McNally, M.T. Mol. Cell (2003) [Pubmed]
  6. Cytoplasmic degradation of splice-defective pre-mRNAs and intermediates. Hilleren, P.J., Parker, R. Mol. Cell (2003) [Pubmed]
  7. Stress granules and processing bodies are dynamically linked sites of mRNP remodeling. Kedersha, N., Stoecklin, G., Ayodele, M., Yacono, P., Lykke-Andersen, J., Fitzler, M.J., Scheuner, D., Kaufman, R.J., Golan, D.E., Anderson, P. J. Cell Biol. (2005) [Pubmed]
  8. Cloning and characterization of human Sep1 (hSEP1) gene and cytoplasmic localization of its product. Sato, Y., Shimamoto, A., Shobuike, T., Sugimoto, M., Ikeda, H., Kuroda, S., Furuichi, Y. DNA Res. (1998) [Pubmed]
WikiGenes - Universities