High impact information on HOXA4

• In a screen for homeobox transcription factors expressed in the embryonic ventral midbrain, Andersson et al. recently identified Lmx1a and Msx1 [1].
• Induction of a mesencephalic phenotype in the 2-day-old chick prosencephalon is preceded by the early expression of the homeobox gene en [2].
• The homeobox gene Hex and the chick Frizbee homologue Crescent are both expressed prominently within anterior definitive endoderm at the time when removal of this tissue results in forebrain defects, and the possible implications of this are discussed [3].
• We have isolated two members of the divergent T-cell leukemia translocation (HOX11/Tlx) homeobox gene family from chick, Tlx-1 and Tlx-3, and show that they are expressed in differentiating neurons of both the peripheral and central nervous systems [4].
• Tlx-1 and Tlx-3 homeobox gene expression in cranial sensory ganglia and hindbrain of the chick embryo: markers of patterned connectivity [4].

Biological context of HOXA4

• Comparison of the avian bsp promoter sequence to those of other genes expressed in vertebrate skeletal tissues, identified the presence of homeobox protein binding sequence motifs for engrailed (en-1) and Msx 2 (Hox 8.1), and two collagen type II gene silencer elements [5].
• A unique mutation of the paired box (Pax)-6 gene (a kind of homeobox gene) was found in a new rat strain "rSey" which showed no induction of both lens and nasal placodes in the homozygote [6].

Anatomical context of HOXA4

• During early stages of normal chick limb development, the homeobox-containing (HOX) gene GHox-4.6 is expressed throughout the posterior mesoderm of the wing bud from which most of the skeletal elements including the digits will develop, whereas GHox-8 is expressed in the anterior limb bud mesoderm which will not give rise to skeletal elements [7].
• Chicken homeobox gene Msx-1: structure, expression in limb buds and effect of retinoic acid [8].
• Goosecoid (gsc) is an evolutionarily conserved homeobox gene expressed in the gastrula organizer region of a variety of vertebrate embryos, including zebrafish, Xenopus, chicken and mouse [9].
• A homeobox gene involved in node, notochord and neural plate formation of chick embryos [10].
• We analyzed the spatial expression patterns of Hox genes belonging to the HoxA and HoxB cluster (Hoxa-4 approximately a-9, Hoxb-5 approximately b-9) in the developing chick digestive tract [11].

Other interactions of HOXA4

• Expression of the chicken homeobox-containing gene GHox-8 during embryonic chick limb development [12].
• We report the cloning and expression pattern of the chicken DLX3 gene, a homeobox gene highly related to the DLX5 gene with regard to both the encoded protein structure and the expression pattern [13].

Analytical, diagnostic and therapeutic context of HOXA4

• The binding profiles of these proteins to the 5'-leader and 5'-upstream sequences of Chox-1.4 and Chox-a coding regions were analyzed by immunoprecipitation and DNase I footprint assays [14].
• PCR also proved to be a rapid method for identifying homeobox sequences from diverse metazoan species [15].

References