Written | 2007-04 | 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. |
Identity |
Alias_names | ZNFN1A2 |
zinc finger protein, subfamily 1A, 2 (Helios) | |
IKAROS family zinc finger 2 (Helios) | |
Alias_symbol (synonym) | Helios |
Other alias | Mouse Ikzf2 |
HGNC (Hugo) | IKZF2 |
LocusID (NCBI) | 22807 |
Atlas_Id | 42885 |
Location | 2q34 [Link to chromosome band 2q34] |
Location_base_pair | Starts at 212999686 and ends at 213150334 bp from pter ( according to hg19-Feb_2009) [Mapping IKZF2.png] |
Fusion genes (updated 2017) | Data from Atlas, Mitelman, Cosmic Fusion, Fusion Cancer, TCGA fusion databases with official HUGO symbols (see references in chromosomal bands) |
ERBB4 (2q34) / IKZF2 (2q34) | IKZF2 (2q34) / BCL11B (14q32.2) | IKZF2 (2q34) / DOCK2 (5q35.1) | |
IKZF2 (2q34) / MICU2 (13q12.11) | IKZF2 (2q34) / SPAG16 (2q34) |
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. |
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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 |
Note | |
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. |
Bibliography |
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 |
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 |
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 |
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 |
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 |
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 |
Citation |
This paper should be referenced as such : |
Sridharan, Rupa ; Smale, Stephen |
IKZF2 (IKAROS family zinc finger 2) |
Atlas Genet Cytogenet Oncol Haematol. 2007;11(4):270-271. |
Free journal version : [ pdf ] [ DOI ] |
On line version : http://AtlasGeneticsOncology.org/Genes/IKZF2ID42885ch2q34.html |
Other Leukemias implicated (Data extracted from papers in the Atlas) [ 2 ] |
t(2;14)(q34;q32) IKZF2/BCL11B
t(2;14)(q34;q32) IKZF2/BCL11B |
Other Solid tumors implicated (Data extracted from papers in the Atlas) [ 1 ] |
t(2;13)(q34;q12) IKZF2/MICU2
|
External links |
REVIEW articles | automatic search in PubMed |
Last year publications | automatic search in PubMed |
© Atlas of Genetics and Cytogenetics in Oncology and Haematology | indexed on : Wed Nov 13 21:29:38 CET 2019 |
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