Disease relevance of PRRX1

• Craniofacial abnormalities induced by ectopic expression of the homeobox gene Hox-1.1 in transgenic mice [1].
• Increase in expression of the homeobox gene, GBX1, in retinol-induced epidermal mucous metaplasia [2].

High impact information on PRRX1

• The homeobox gene GBX2, a target of the myb oncogene, mediates autocrine growth and monocyte differentiation [3].
• The homeobox gene goosecoid and the origin of organizer cells in the early chick blastoderm [4].
• Homeobox gene expression correlated with the bifurcation process of limb cartilage development [5].
• Homeobox genes, which specify positional information in Drosophila and possibly in vertebrate embryogenesis, are among the candidate responsive genes [6].
• Early stages of motor neuron differentiation revealed by expression of homeobox gene Islet-1 [7].

Biological context of PRRX1

• To further define the functions of MHox during embryogenesis, we have cloned its chicken homolog, termed gMHox, and analyzed its properties and detailed expression patterns [8].
• Such a pattern of expression suggests that gMHox may participate in maintenance of mesenchymal cell lineages derived from both mesoderm and the neural crest and in patterning of the limbs and the face [8].
• Activation of myogenesis by the homeobox gene Lbx1 requires cell proliferation [9].
• A human craniofacial cDNA library was screened with a degenerate oligonucleotide probe based on the conserved third helix of homeobox genes [10].
• Identification and genetic mapping of a homeobox gene to the 4p16.1 region of human chromosome 4 [10].

Anatomical context of PRRX1

• The expression pattern of the chick homeobox gene gMHox suggests a role in patterning of the limbs and face and in compartmentalization of somites [8].
• Removal of the surface ectoderm overlying the somites has no visible effect on the architecture of somites but results in the failure of gMHox to be expressed in the underlying dermatome, suggesting that regulation of gMHox expression in these cells is dependent on cues emanating from the surface ectoderm [8].
• Furthermore, PRX1 expression preceded the segregation of very distinct nonmuscular cells and smooth muscle cells in the media of the great arteries [11].
• PRX2 patterns deviated at later stages from those of PRX1 and showed specific and high transcript levels in the ductus arteriosus from embryonic day 6 onward [11].
• Prx2 is never expressed in the brain, whereas Prx1 is expressed, from at least day 9.5 onwards, in a unique distinct domain in the ventral part of the hypothalamus, as well as in a broader region of the telencephalon [12].

Associations of PRRX1 with chemical compounds

• Expression of a homeobox gene in the chick wing bud following application of retinoic acid and grafts of polarizing region tissue [13].
• A chicken DNA fragment, which was isolated from a cosmid genomic library using a murine homeobox probe, is shown here to be a likely candidate for encoding a protein homologous to the bovine B15 subunit of NADH ubiquinone oxidoreductase [14].

Analytical, diagnostic and therapeutic context of PRRX1

• In the chicken, we isolated BAC clones containing PRRX1, SELE, and SCYC1 and positioned them by fluorescent in situ hybridization [15].
• We have used degenerate oligonucleotide primers from highly conserved domains in the homeobox motif to amplify homeobox gene segments from chick embryo limb bud cDNAs using the polymerase chain reaction [16].
• In an effort to demonstrate a similar role for such genes during ear development in the chicken, we present a detailed expression study of two related homeobox-containing genes, SOHo-1 and GH6, using in situ hybridization [17].
• For this the homeobox containing region of the porcine gsc was isolated using RT-PCR [18].

References