World Library  
Flag as Inappropriate
Email this Article


Article Id: WHEBN0014764246
Reproduction Date:

Title: Hhex  
Author: World Heritage Encyclopedia
Language: English
Subject: Homeobox, Promyelocytic leukemia protein, Transcription factors, NeuroD, EMX homeogene
Publisher: World Heritage Encyclopedia


Hematopoietically expressed homeobox

PDB rendering based on 2e1o.
Available structures
PDB Ortholog search: PDBe, RCSB
External IDs GeneCards:
RNA expression pattern
Species Human Mouse
RefSeq (mRNA)
RefSeq (protein)
Location (UCSC)
PubMed search

Hematopoietically-expressed homeobox protein HHEX is a protein that in humans is encoded by the HHEX gene.[1][2][3] This gene encodes a member of the homeobox family of transcription factors, many of which are involved in developmental processes. Expression in specific hematopoietic lineages suggests that this protein may play a role in hematopoietic differentiation.[3]

The HHEX transcription factor acts as a promoter in some instances and an inhibitor others.[4][5] It interacts with a number of other signaling molecules to play an important role in the development of multiple organs, such as the liver, thyroid and forebrain.[6] HHEX serves to repress VEGFA, another protein which is important in endothelial cell development.[7] SCL, a significant transcription factor for blood and endothelial cell differentiation, is shown to interact with HHEX to promote the correct development of the hematopoiesis process.[8] HHEX appears to work together with another molecule, β-catenin, for the development of the anterior organizer.[9] It also contributes to developmental remodeling and stabilization of endothelial cells in an unborn organism.[7] The importance of this transcription factor is illustrated by the inability of HHEX knockout mice embryos to survive gestation. Without the expression of HHEX, these mice embryos die in utero between Day 13 and Day 16.[7] HHEX knockout mice display a range of abnormalities including forebrain abnormalities in various levels of severity, as well as a number of other defects including heart, vasculature, liver, monocyte, and thyroid abnormalities.[6][7]


HHEX has been shown to interact with Promyelocytic leukemia protein.[10]


  1. ^ Bedford FK, Ashworth A, Enver T, Wiedemann LM (May 1993). "HEX: a novel homeobox gene expressed during haematopoiesis and conserved between mouse and human". Nucleic Acids Res 21 (5): 1245–9.  
  2. ^ Hromas R, Radich J, Collins S (Oct 1993). "PCR cloning of an orphan homeobox gene (PRH) preferentially expressed in myeloid and liver cells". Biochem Biophys Res Commun 195 (2): 976–83.  
  3. ^ a b "Entrez Gene: HHEX hematopoietically expressed homeobox". 
  4. ^ Denson, Lee; Karpen, Saul; Bogue, Clifford; Jacobs, Harris (August 2000). "Divergent homeobox gene Hex regulates promoter of the Na+-dependent bile acid cotransporter". American Journal of Physiology – Gastrointestinal and Liver Physiology 279 (2): 347–355. 
  5. ^ Brickman, Joshua; Jones, C; Clements, Melanie; Smith, J; Beddington, Rosa (June 2000). "Hex is a transcriptional repressor that contributes to anterior identity and suppresses Spemann organiser function". Development 127: 2303–2315. 
  6. ^ a b Martinez Barbera, Juan; Clements, Melanie; Thomas, Paul; Rodriguez, Tristan; Meloy, Denise; Kioussis, Dimitris; Beddington, Rosa (May 2000). "The homeobox gene Hex is required in definitive endodermal tissues for normal forebrain, liver and thryoid formation". Development 127: 2433–2445. 
  7. ^ a b c d Hallaq, Haifa; Pinter, Emese; Enciso, Josephine; McGrath, James; Zeiss, Caroline; Brueckner, Martina; Madri, Joseph; Jacobs, Harris; Wilson, Christine; Vasavada, Hemaxi; Jiang, Xiaobing; Bogue, Clifford (October 2004). "A null mutation of Hhex results in abnormal cardiac development, defective vasculogenesis and elevated Vegfa levels". Development 131: 5197–5209.  
  8. ^ Liao, Wayne; Ho, Chi-Yip; Yi, Lin Yan; Postlewait, John; Stainier, Didier (September 2000). "Hhex and Scl function in parallel to regulate early endothelial and blood differentiation in zebrafish". Development 127: 4303–4313. 
  9. ^ Zamparini, Andrea; Watts, Tim; Gardner, Clare; Tomlinson, Simon; Johnston, Geoffrey; Brickman, Joshua (September 2006). "Hex acts with β-catenin to regulate anteroposterior patterning via a Groucho-related co-repressor and Nodal". Development 133: 3709–3722.  
  10. ^ Topcu, Z; Mack D L; Hromas R A; Borden K L (Nov 1999). "The promyelocytic leukemia protein PML interacts with the proline-rich homeodomain protein PRH: a RING may link hematopoiesis and growth control". Oncogene (ENGLAND) 18 (50): 7091–100.  

Further reading

External links

This article incorporates text from the United States National Library of Medicine, which is in the public domain.

This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.

Copyright © World Library Foundation. All rights reserved. eBooks from Hawaii eBook Library are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.