XIST

XIST
Identifiers
AliasesXIST, DXS1089, DXS399E, LINC00001, NCRNA00001, SXI1, swd66, X inactive specific transcript (non-protein coding), X inactive specific transcript, Xist
External IDsOMIM: 314670; MGI: 98974; GeneCards: XIST; OMA:XIST - orthologs
Orthologs
SpeciesHumanMouse
Entrez

7503

213742

Ensembl

ENSG00000229807

ENSMUSG00000086503

UniProt

n
a

n/a

RefSeq (mRNA)

n/a

n/a

RefSeq (protein)

n/a

n/a

Location (UCSC)Chr X: 73.82 – 73.85 MbChr X: 102.5 – 102.53 Mb
PubMed search[3][4]
Wikidata
View/Edit HumanView/Edit Mouse

Xist (X-inactive specific transcript) is a non-coding RNA transcribed from the X chromosome of the placental mammals that acts as a major effector of the X-inactivation process.[5] It is a component of the Xic – X-chromosome inactivation centre[6] – along with two other RNA genes (Jpx and Ftx) and two protein genes (Tsx and Cnbp2).[7]

The Xist RNA, a large (17 kb in humans)[8] transcript, is expressed on the inactive chromosome and not on the active one. It is processed in a similar way to mRNAs, through splicing and polyadenylation. However, it remains untranslated. It has been suggested that this RNA gene evolved at least partly from a protein-coding gene that became a pseudogene.[9] The inactive X chromosome is coated with this transcript, which is essential for the inactivation.[10] X chromosomes lacking Xist will not be inactivated, while duplication of the Xist gene on another chromosome causes inactivation of that chromosome.[11]

The human Xist gene was discovered by Andrea Ballabio through a cDNA library screening and then characterized in collaboration with Carolyn J. Brown and Hunt Willard.[12][13]

  1. ^ a b c GRCh38: Ensembl release 89: ENSG00000229807 – Ensembl, May 2017
  2. ^ a b c GRCm38: Ensembl release 89: ENSMUSG00000086503 – Ensembl, May 2017
  3. ^ "Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
  4. ^ "Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
  5. ^ "Entrez Gene: XIST X (inactive)-specific transcript".
  6. ^ Chow JC, Yen Z, Ziesche SM, Brown CJ (2005). "Silencing of the mammalian X chromosome". Annual Review of Genomics and Human Genetics. 6: 69–92. doi:10.1146/annurev.genom.6.080604.162350. PMID 16124854.
  7. ^ Chureau C, Prissette M, Bourdet A, Barbe V, Cattolico L, Jones L, Eggen A, Avner P, Duret L (June 2002). "Comparative sequence analysis of the X-inactivation center region in mouse, human, and bovine". Genome Research. 12 (6): 894–908. doi:10.1101/gr.152902. PMC 1383731. PMID 12045143.
  8. ^ Brown CJ, Hendrich BD, Rupert JL, Lafrenière RG, Xing Y, Lawrence J, Willard HF (October 1992). "The human XIST gene: analysis of a 17 kb inactive X-specific RNA that contains conserved repeats and is highly localized within the nucleus". Cell. 71 (3): 527–42. doi:10.1016/0092-8674(92)90520-M. PMID 1423611. S2CID 13141516.
  9. ^ Duret L, Chureau C, Samain S, Weissenbach J, Avner P (June 2006). "The Xist RNA gene evolved in eutherians by pseudogenization of a protein-coding gene". Science. 312 (5780): 1653–1655. Bibcode:2006Sci...312.1653D. doi:10.1126/science.1126316. PMID 16778056. S2CID 28145201.
  10. ^ Ng K, Pullirsch D, Leeb M, Wutz A (January 2007). "Xist and the order of silencing" (Review Article). EMBO Reports. 8 (1): 34–39. doi:10.1038/sj.embor.7400871. PMC 1796754. PMID 17203100. Figure 1 Xist RNA encompasses the X from which it is transcribed.
  11. ^ Penny GD, Kay GF, Sheardown SA, Rastan S, Brockdorff N (1996). "Requirement for Xist in X chromosome inactivation". Nature. 379 (6561): 131–7. Bibcode:1996Natur.379..131P. doi:10.1038/379131a0. PMID 8538762. S2CID 4329368. Closed access icon
  12. ^ Brown CJ, Ballabio A, Rupert JA, Lafreniere RG, Grompe M, Tonlorenzi R, Willard HF (Jan 1991). "A gene from the region of the human X inactivation centre is expressed exclusively from the inactive X chromosome". Nature. 349 (6304): 38–44. Bibcode:1991Natur.349...38B. doi:10.1038/349038a0. PMID 1985261. S2CID 4332325.
  13. ^ Lee JT (2011). "Gracefully ageing at 50, X-chromosome inactivation becomes a paradigm for RNA and chromatin control". Nature Reviews Molecular Cell Biology. 12 (12): 815–26. doi:10.1038/nrm3231. PMID 22108600. S2CID 21881827.