Homeobox protein Hox-A3 is a protein that in humans is encoded by the HOXA3 gene. [5] [6] [7]
In vertebrates, the genes encoding the class of transcription factors called homeobox genes are found in clusters named A, B, C, and D on four separate chromosomes. Expression of these proteins is spatially and temporally regulated during embryonic development. This gene is part of the A cluster on chromosome 7 and encodes a DNA-binding transcription factor which may regulate gene expression, morphogenesis, and differentiation. Three transcript variants encoding two different isoforms have been found for this gene. [7]
During normal fetal development, HoxA3 is expressed in mesenchymal neural crest cells and endodermal cells found in the third pharyngeal pouch. [8] Expression of HoxA3 in these cells affects the proper formation of the thymus, thyroid, and parathyroid organs. [9] [10] While the gene does not seem to affect the proliferation or migration of the pharyngeal neural crest cells, it does appear to trigger cellular differentiation events required to form these organs. [9] Knockout of HoxA3 leads to failure in forming the thymus (athymia) and parathyroid gland (aparthyroidism). [10] Mutant HoxA3 also causes a reduction in thyroid size. While the follicular and parafollicular cells still differentiate, their numbers are reduced and they are not evenly distributed throughout the gland. [9] Mutant HoxA3 models show similar phenotypes as those seen in DiGeorge's syndrome, and it is possible that the two are linked. [9]
Homeobox D10, also known as HOXD10, is a protein which in humans is encoded by the HOXD10 gene.
Homeobox protein Hox-A5 is a protein that in humans is encoded by the HOXA5 gene.
Homeobox protein Hox-A11 is a protein that in humans is encoded by the HOXA11 gene.
Homeobox protein Hox-B5 is a protein that in humans is encoded by the HOXB5 gene.
Homeobox protein Hox-C8 is a protein that in humans is encoded by the HOXC8 gene.
Homeobox protein Hox-A7 is a protein that in humans is encoded by the HOXA7 gene.
Homeobox protein Hox-B2 is a protein that in humans is encoded by the HOXB2 gene.
Homeobox protein Hox-B9 is a protein that in humans is encoded by the HOXB9 gene.
Homeobox protein Hox-D3 is a protein that in humans is encoded by the HOXD3 gene.
Homeobox protein Hox-B3 is a protein that in humans is encoded by the HOXB3 gene.
Homeobox protein Hox-C4 is a protein that in humans is encoded by the HOXC4 gene.
Homeobox A4, also known as HOXA4, is a protein which in humans is encoded by the HOXA4 gene.
Homeobox protein Hox-C6 is a protein that in humans is encoded by the HOXC6 gene. Hox-C6 expression is highest in the fallopian tube and ovary. HoxC6 has been highly expressed in many types of cancers including prostate, breast, and esophageal squamous cell cancer.
Homeobox protein Hox-D4 is a protein that in humans is encoded by the HOXD4 gene.
Homeobox protein Hox-B8 is a protein that in humans is encoded by the HOXB8 gene.
Homeobox protein Hox-C9 is a protein that in humans is encoded by the HOXC9 gene.
Homeobox protein Hox-D1 is a protein that in humans is encoded by the HOXD1 gene.
Homeobox protein Hox-C10 is a protein that in humans is encoded by the HOXC10 gene.
Homeobox protein Hox-A6 is a protein that in humans is encoded by the HOXA6 gene.
Homeobox protein Hox-A2 is a protein that in humans is encoded by the HOXA2 gene.
This article incorporates text from the United States National Library of Medicine, which is in the public domain.