Ftx, a conserved functional long ncRNA, which located in the cis-acting regulatory region of the imprinted X-chromosome inactivation(XCI), is a positive regulator of Xist.
FTX, FTX transcript, XIST regulator (non-protein coding)(HGNC nomenclature)
"five prime to XIST", FLJ33139, LINC00182 
Ftx is specifically upregulated during female ES cell differentiation at the onset of XCI. Loss of Ftx expression through the deletion of the promoter region leads to local alteration in the chromatin structure. More importantly, Ftx impacts on gene expression within theXic and in particular on Xist, as Xist is significantly downregulated in the absence of Ftx . Disruption of Ftx did not affect the survival of female embryos or expression of Xist and other X-linked genes in the preimplantation female embryos, which indicates that Ftx is dispensable for imprinted XCI in preimplantation embryos .
It produces a transcript with no apparent coding potential that predominantly remains in the nucleus .
FTX identified as chromatin-associated lncRNA was predominantly downregulated in breast tumor .
Ftx is well conserved during evolution and contains several microRNAs (miRs) which are also conserved .
Labs working on this lncRNA
Unité de Génétique Moléculaire Murine, URA 2578, Institut Pasteur, Paris, France .
Department of Epigenetics, Medical Research Institute, Tokyo Medical & Dental University, 1-5-45 Yushima Bunkyo-ku, Tokyo, 113-8510, Japan .
Young Investigators Group Bioinformatics and Transcriptomics, Department Proteomics, Helmholtz Centre for Environmental Research - UFZ, Leipzig, Germany, and Department for Computer Science, University of Leipzig, Leipzig, Germany; RNomics Group, Department Diagnostics, Fraunhofer Institute for Cell Therapy and Immunology - IZI, Leipzig, Germany .
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 Chureau C, Chantalat S, Romito A, Galvani A, Duret L, Avner P, et al. Ftx is a non-coding RNA which affects Xist expression and chromatin structure within the X-inactivation center region[J]. Human molecular genetics. 2011,20(4):705-18.
- ↑ 2.0 2.1 Soma M, Fujihara Y, Okabe M, Ishino F, Kobayashi S. Ftx is dispensable for imprinted X-chromosome inactivation in preimplantation mouse embryos[J]. Scientific reports. 2014,4:5181.
- ↑ 3.0 3.1 3.2 Soma M, Fujihara Y, Okabe M, Ishino F, Kobayashi S. Ftx is dispensable for imprinted X-chromosome inactivation in preimplantation mouse embryos[J]. Scientific reports. 2014,4:5181.