Biology:HOXB6

Short description: Protein-coding gene in the species Homo sapiens

Generic protein structure example

Homeobox protein Hox-B6 is a protein that in humans is encoded by the HOXB6 gene.

Function

This gene is a member of the Antp homeobox family and encodes a protein with a homeobox DNA-binding domain. It is included in a cluster of homeobox B genes located on chromosome 17. The encoded protein functions as a sequence-specific transcription factor that is involved in development, including that of lung and skin, and has been localized to both the nucleus and cytoplasm. Altered expression of this gene or a change in the subcellular localization of its protein is associated with some cases of acute myeloid leukemia and colorectal cancer.

During development

HOX B6 gene is only expressed in erythoid progenitor cells, which are the precursor to red blood cells used for transport of oxygen and carbon dioxide throughout the body. During development, the formation of the HOX gene factor happens in the first stages of fetal development, namely soon after the establishment of the mesoderm, which is the “middle layer” of the future embryo. However, HOX B6 is only expressed once the undifferentiated stem cells of the embryo distinguish themselves into the erythpoietic phase. The research has shown that HOX B6 is not expressed in hematopoietic stem cells located in the red bone marrow, which are the precursor cells to all types of blood cells, or primordial germ cells (PGCs), the precursor to cells passed on in each generation. Since it is a transcriptional factor, HOX B6 regulates erythpoigenesis (red blood cell formation) using mRNA as the basis for certain protein productions. The specific gene factor for erytopoigenesis has relatively been unobserved in the scientific community, and no known diseases have been associated with a defect HOX B6 gene. However, it has been shown in correlation with major skeletal deformations.

HOXB6 is a structural protein that has been shown to influence the growth and differentiation of the different blood lineages. This gene has also been shown to encourage the growth of granulocytes and monocytes, but at the cost of other blood cells. HOXB6 has the ability to cause the indefinite proliferation of murine marrow cells, as well as expand hematopoietic stem cells. When expressed abnormally, HOXB6 displays many characteristics of a potent oncoprotein. An oncoprotein can cause the transformation of a normal cell into a tumor cell. Overexpression of HOXB6, along with the addition of MEIS1 protein, has been implicated in the development of acute myeloid leukemia (AML). Acute myeloid leukemia is a cancer of the blood cells, specifically the leukocytes. The chromosomal irregularity most frequently seen in HOXB6 AML is a reappearing interstitial deletion of chromosome 2. Fundamental HOXB6 expression stops myeloid differentiation and debilitates erythropoiesis, megakaryopoiesis, and lymphopoiesis.

See also

• Homeobox

Further reading

• "Dominant mutation of the murine Hox-2.2 gene results in developmental abnormalities". The Journal of Experimental Zoology 264 (3): 323–36. Dec 1992. doi:10.1002/jez.1402640311. PMID 1358998. 
• "Alternative splicing of the HOX 2.2 homeobox gene in human hematopoietic cells and murine embryonic and adult tissues". Nucleic Acids Research 19 (3): 539–45. Feb 1991. doi:10.1093/nar/19.3.539. PMID 1672751. 
• "Expression of HOX homeogenes in human neuroblastoma cell culture lines". Differentiation; Research in Biological Diversity 45 (1): 61–9. Oct 1990. doi:10.1111/j.1432-0436.1990.tb00458.x. PMID 1981366. 
• "Differential expression of human HOX-2 genes along the anterior-posterior axis in embryonic central nervous system". Differentiation; Research in Biological Diversity 40 (3): 191–7. Jun 1989. doi:10.1111/j.1432-0436.1989.tb00598.x. PMID 2570724. 
• "Lineage-restricted expression of homeobox-containing genes in human hematopoietic cell lines". Proceedings of the National Academy of Sciences of the United States of America 86 (21): 8536–40. Nov 1989. doi:10.1073/pnas.86.21.8536. PMID 2573064. Bibcode: 1989PNAS...86.8536S. 
• "The human HOX gene family". Nucleic Acids Research 17 (24): 10385–402. Dec 1989. doi:10.1093/nar/17.24.10385. PMID 2574852. 
• "Organization of human class I homeobox genes". Genome 31 (2): 745–56. 1990. doi:10.1139/g89-133. PMID 2576652. 
• "A moderately frequent RFLP identified by both SacI and BanII with a probe from the HOX2 locus in man (17q11-17q22)". Nucleic Acids Research 15 (15): 6311. Aug 1987. doi:10.1093/nar/15.15.6311. PMID 2888083. 
• "Human DNA sequences homologous to a protein coding region conserved between homeotic genes of Drosophila". Cell 38 (3): 667–73. Oct 1984. doi:10.1016/0092-8674(84)90261-7. PMID 6091895. 
• "Pbx proteins display hexapeptide-dependent cooperative DNA binding with a subset of Hox proteins". Genes & Development 9 (6): 663–74. Mar 1995. doi:10.1101/gad.9.6.663. PMID 7729685. 
• "Homeobox genes: potential candidates for the transcriptional control of the transformed and invasive phenotype". Biochemical Pharmacology 47 (1): 137–43. Jan 1994. doi:10.1016/0006-2952(94)90447-2. PMID 7906121. https://zenodo.org/record/1253822. 
• "Fine mapping of human HOX gene clusters". Cytogenetics and Cell Genetics 73 (1–2): 114–5. 1996. doi:10.1159/000134320. PMID 8646877. 
• "A genome screen in multiple sclerosis reveals susceptibility loci on chromosome 6p21 and 17q22". Nature Genetics 13 (4): 464–8. Aug 1996. doi:10.1038/ng0896-464. PMID 8696343. 
• "Mammalian homeobox B6 expression can be correlated with erythropoietin production sites and erythropoiesis during development, but not with hematopoietic or nonhematopoietic stem cell populations". Blood 89 (8): 2723–35. Apr 1997. doi:10.1182/blood.V89.8.2723. PMID 9108390. 
• "Human colorectal carcinogenesis is associated with deregulation of homeobox gene expression". Biochemical and Biophysical Research Communications 232 (3): 742–8. Mar 1997. doi:10.1006/bbrc.1997.6364. PMID 9126347. 
• "Modulation of homeobox B6 and B9 genes expression in human leukemia cell lines during myelomonocytic differentiation". Leukemia & Lymphoma 31 (5–6): 599–608. Nov 1998. doi:10.3109/10428199809057620. PMID 9922051. 
• "Phylogenetically conserved CK-II phosphorylation site of the murine homeodomain protein Hoxb-6". The Journal of Experimental Zoology 285 (1): 76–84. Apr 1999. doi:10.1002/(SICI)1097-010X(19990415)285:1<76::AID-JEZ9>3.0.CO;2-K. PMID 10327653. 
• "Deregulated expression of homeobox-containing genes, HOXB6, B8, C8, C9, and Cdx-1, in human colon cancer cell lines". Biochemical and Biophysical Research Communications 272 (2): 513–8. Jun 2000. doi:10.1006/bbrc.2000.2804. PMID 10833444. 

External links

• HOXB6+protein,+human at the US National Library of Medicine Medical Subject Headings (MeSH)
• Overview of all the structural information available in the PDB for UniProt: Q24645 (Drosophila subobscura Homeotic protein antennapedia) at the PDBe-KB.

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