Disease relevance of Hoxc

• We have studied the expression of nine homeobox genes from Hox 1, Hox 2, Hox 3 and Hox 5 clusters in human embryonal carcinoma (EC) cell lines analyzed as both stem cells and after exposure to the differentiation-inducing agents retinoic acid (RA), hexamethylenebisacetamide (HMBA) and bromodeoxyuridine (BUdR) [1].

High impact information on Hoxc

• Using Northern blot analysis and in situ hybridization to mouse tissue sections, the spatially restricted expression of a newly identified mouse homoeo box locus, Hox-3, within the central nervous system of newborn and adult mice has been demonstrated [2].
• 2. Furthermore, we have identified another zebrafish gene related to hox-2.2 which appears to correspond to the Hox-6.1 gene of the murine Hox-3 locus [3].
• Primary structure and developmental expression pattern of Hox 3.1, a member of the murine Hox 3 homeobox gene cluster [4].
• It is possible that a pair of Dlx genes linked to the Hoxc cluster has been lost from mammals [5].
• Other mouse homeo box-containing genes of the Antennapedia class (class I) map to mouse chromosomes 6 (Hox-1, proximal to the IgK locus) and 15 (Hox-3) [6].

Biological context of Hoxc

• Results support genome duplication before divergence of zebrafish and pufferfish lineages, followed by loss of a Hoxc cluster in the pufferfish lineage and loss of a Hoxd cluster in the zebrafish lineage [7].
• Alternatively, Hox-3 may be most distal, and several double recombinations at the telomere lead to map expansion [8].
• Thus, the kinetics are different from the previously described homeobox transcripts Hox 1.1 and Hox 3 [9].
• Hox3 genes coordinate mechanisms of genetic suppression and activation in the generation of branchial and somatic motoneurons [10].
• 1. In situ hybridization of mouse metaphase chromosomes shows this Hox-6 locus to be located on chromosome 14 (14E2) [11].

Anatomical context of Hoxc

• Hoxc family transcription factors are expressed in different domains along the rostrocaudal (RC) axis of the developing spinal cord and they define RC identities of spinal neurons [12].
• Our previous study using an in vitro assay system demonstrated that Fgf and Gdf11 signals located around Hensen's node of chick embryos have the ability to induce profiled Hoxc protein expression [12].
• These data suggest a specific role for the AbdB-related Hoxc genes in patterning the hindlimb and pelvic girdle, which is separate from a second role relevant for both hind- and forelimb development [13].
• The anterior boundaries of Hox-3.5 expression in the hindbrain and prevertebral column lie anterior to those of Hox-3.4 and all other, more 5'-located Hox-3 genes [14].

Other interactions of Hoxc

• The murine homeobox-containing gene Hox-3.2 is the most 5' member of the Hox-3 complex on chromosome 15 isolated to date [15].
• Hox-3.6: isolation and characterization of a new murine homeobox gene located in the 5' region of the Hox-3 cluster [16].
• As a prerequisite for studying the role of the AbdB-related Hoxc genes during limb development, we have isolated and mapped the three predicted AbdB-related Hoxc-11, -12, and -13 loci, thus defining the 5' end of the Hoxc cluster [13].

References