Atlas of Genetics and Cytogenetics in Oncology and Haematology
Dear Colleagues,
The Atlas, once more, is in great danger, and I will have to proceed to a collective economic lay-off of all the team involved in the Atlas before the begining of April 2015 (a foundation having suddenly withdrawn its commitment to support the Atlas). I ask you herein if any Scientific Society (a Society of Cytogenetics, of Clinical Genetics, of Hematology, or a Cancer Society, or any other...), any University and/or Hospital, any Charity, or any database would be interested in taking over the Atlas, in whole or in part. If taking charge of the whole lot is too big, a consortium of various actors could be the solution (I am myself trying to find partners). Could you please spread the information, contact the relevant authorities, and find partners.
Survival of the Atlas will be critically dependant upon your ability to find solutions (and urgently!).
Kind regards.
Jean-Loup Huret jlhuret@AtlasGeneticsOncology.org
Donations are also welcome
If each casual visitor gives 3 Euros or Dollars, the Atlas is saved in a week !
If each professional gives 100 Euros or Dollars once a year (now), the Atlas is saved in 2 weeks !
Don't let the Atlas imminent demise
Note: we send fiscal receipts for donations equal or above 50 Euros or Dollars
IKZF2 (IKAROS family zinc finger 2)
| Identity |
| Other names | Helios |
| ZNFN1A2 | |
| Mouse Ikzf2 | |
| HGNC (Hugo) | IKZF2 |
| LocusID (NCBI) | 22807 |
| Location | 2q34 |
| Location_base_pair | Starts at 213864411 and ends at 214016333 bp from pter ( according to hg19-Feb_2009) [Mapping] |
| Note | Belongs to the Ikaros family of zinc finger containing DNA binding proteins. |
| DNA/RNA |
| Description | 143kb encoding 7 exons. |
| Transcription | 12kb transcript, alternatively spliced to give two predominant isoforms. |
| Protein |
| Note | 526 amino acids. Mouse protein migrates at 70kD. |
 | |
| Helios with the zinc finger domain shown as blocks and the exon junctions in black lines. | |
| Description | Largest isoform contains four N-terminal zinc fingers used for DNA binding and two C terminal zinc fingers for homodimerization and heterodimerization with other Ikaros family members. |
| Expression | Largely restricted to the thymus. In mice, besides thymocytes and T cells, low levels are found in proB cells and bone marrow multipotent progenitors. |
| Localisation | Nuclear. Often localizes to the pericentric heterochromatin as punctate spots in cycling cells, with diffuse nuclear localization in non-cycling cells. |
| Function | Helios is thought to be important for T cell development and may function as a repressor of transcription. However, Helios mutant mice have not been reported. In mice, Helios can recruit the NuRD chromatin remodeling complex to the pericentric heterochromatin. |
| Homology | High level of identity to Ikaros over the zinc finger domains. |
| Implicated in |
| Entity | Leukemia |
| Note | Shorter isoforms of Helios are expressed in certain human leukemias. They may function as dominant negative inhibitors of full-length proteins due to the lack of DNA binding domain. However, dominant negative functions have not been demonstrated experimentally. |
| Disease | T cell acute lymphoblastic leukemia. |
| Entity | Lymphoma |
| Note | Overexpression of Helios in B cells of mice promotes lymphomagenesis. Overexpression of a DNA binding mutant in hematopoietic progenitors leads to aggressive and transplantable T cell lymphomas in 60% of the mice. |
| External links |
| Bibliography |
| Helios, a T cell-restricted Ikaros family member that quantitatively associates with Ikaros at centromeric heterochromatin. |
| Hahm K, Cobb BS, McCarty AS, Brown KE, Klug CA, Lee R, Akashi K, Weissman IL, Fisher AG, Smale ST |
| Genes & development. 1998 ; 12 (6) : 782-796. |
| PMID 9512513 |
| Helios, a novel dimerization partner of Ikaros expressed in the earliest hematopoietic progenitors. |
| Kelley CM, Ikeda T, Koipally J, Avitahl N, Wu L, Georgopoulos K, Morgan BA |
| Current biology : CB. 1998 ; 8 (9) : 508-515. |
| PMID 9560339 |
| Human Helios, an Ikaros-related zinc finger DNA binding protein: cDNA cloning and tissue expression pattern. |
| Hosokawa Y, Maeda Y, Seto M |
| Immunogenetics. 1999 ; 50 (1-2) : 106-108. |
| PMID 10541817 |
| Overexpression of novel short isoforms of Helios in a patient with T-cell acute lymphoblastic leukemia. |
| Nakase K, Ishimaru F, Fujii K, Tabayashi T, Kozuka T, Sezaki N, Matsuo Y, Harada M |
| Experimental hematology. 2002 ; 30 (4) : 313-317. |
| PMID 11937265 |
| Transgenic expression of Helios in B lineage cells alters B cell properties and promotes lymphomagenesis. |
| Dovat S, Montecino-Rodriguez E, Schuman V, Teitell MA, Dorshkind K, Smale ST |
| Journal of immunology (Baltimore, Md. : 1950). 2005 ; 175 (6) : 3508-3515. |
| PMID 16148093 |
| Expression of a non-DNA-binding isoform of Helios induces T-cell lymphoma in mice. |
| Zhang Z, Swindle CS, Bates JT, Ko R, Cotta CV, Klug CA |
| Blood. 2007 ; 109 (5) : 2190-2197. |
| PMID 17110463 |
| REVIEW articles | automatic search in PubMed |
| Last year publications | automatic search in PubMed |
| Contributor(s) |
| Written | 04-2007 | Rupa Sridharan, Stephen Smale |
| Room 6730 MacDonald Research Laboratories, Howard Hughes Medical Institute, 675 Charles Young Drive South, University of California, Los Angeles, CA 90095-1662, USA. |
| Citation |
| This paper should be referenced as such : |
| Sridharan R, Smale S |
| IKZF2 (IKAROS family zinc finger 2); |
| Atlas Genet Cytogenet Oncol Haematol. April 2007 |
| Free journal version : [ pdf ] [ DOI ] |
| URL : http://AtlasGeneticsOncology.org/Genes/IKZF2ID42885ch2q34.html |
| © Atlas of Genetics and Cytogenetics in Oncology and Haematology | indexed on : Tue Feb 17 20:15:16 CET 2015 |
For comments and suggestions or contributions, please contact us