Hoxa5

..Whereas HoxA5 is down regulated in active angiogenic endothelial cells (EC), sustained expression of HoxA5 induces TSP-2 and ..

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..Overlap among DNA-binding sites suggests that regulation imparted by certain cis-elements may be integrated by these different factors...

..Using WebQTL's extensive database of published BXD phenotypes, we also detected a strong and potentially biologically meaningful correlation between hippocampal volume and the acoustic startle response...

..Gene array analysis identified differentially expressed genes. Expression of HoxA5, a tumor suppressor gene, was decreased following 9 wk of treatment with 27 mg CSC, and returned to control levels ..

We have previously described a Hoxa5 mutant mouse line in which specification of axial identity is perturbed and viability is markedly reduced...

..The analysis of double, triple and even quadruple mutants should determine the ways in which these Hox genes interact in order to specify the multitude of tissues in a restricted region of the developing mouse embryo...

..These results demonstrate that the Hoxa-5 gene has an important role in the establishment of the skeleton during development and contributes to the process whereby the axial structures are determined...

..6 transcripts were present both in embryonic total RNA and in embryonal carcinoma cell cytoplasmic RNA. These various transcripts are probably generated by an alternative splicing mechanism and may thus encode a set of related proteins...

..5 onwards. We discuss the possibility that members of the murine Polycomb-group can form multimeric protein complexes of different compositions with varying affinity or specificity for different subsets of Hox genes...

Genetic analyses have revealed the essential role of the murine Hoxa5 gene for the correct specification of the cervical and upper thoracic region of the skeleton, and for the normal organogenesis and function of the respiratory tract, ..

..3. The results suggest that mouse Hox-1.3 cannot only substitute functionally for Drosophila Scr in the determination of external structures but also can participate in the regulatory hierarchy of insect organogenesis...

..Since expression of Hoxa-5 is confined to the mesenchymal component of the developing trachea and lung, the effects observed in epithelial cells may result from a disruption of normal epithelial-mesenchymal interactions...

..Several Hox genes are expressed in normal and neoplastic mammary glands. Using Hoxa5 mutant mice, we showed that Hoxa5-/- females present nursing defects...

..It has been suggested that HOXA5 possesses growth-suppressive properties through activation of p53 expression in human breast tissue...

..In transgenic mice, gene fusions between Hoxa5 (previously called Hox-1...

..Hox1-3 is shown to be a member of a cluster of at least four homeo-boxes lying within a 75-kb segment of DNA on mouse chromosome 6. The structure of the whole cluster, the Hox-1 locus is presented...

..As for other Hox genes, region-specific expression of Hoxa5 appears to be important for correct function during development...

..This complex pattern of expression suggests that Hox 1.3 may provide a function required by many cell types in addition to any role it may have in morphogenesis...

..We have examined the role of Hox genes in gut patterning using the Hoxa5(-/-) mice as a model. Hoxa5 is expressed in a dynamic fashion in the mesenchymal component of the developing gut...

..This overexpression correlated with changes in the normal developmental program of the gut, resulting in an inherited abnormal phenotype known as megacolon...

..A phenotypical survey of the Hoxa5(-/-) mutant mice shows that the surviving mutants display symptoms of hypothyroidism, including transient growth ..

..4 expression within the spinal cord and the testis are very similar to those shown by a neighbouring Hox-3 gene (Hox-3.3), but they are quite different from those shown by Hox-1 genes (Hox-1.2, -1.3 and -1.4)...

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Analysis of the Hoxa5(-/-) mutants has revealed the critical role of Hoxa5 in survival, specification of axial identity, and ontogeny of organs, including the respiratory tract...

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..Multiple overlapping transcriptional units exist at the Hoxa5 locus reflecting the complexity of Hox clustering: a major form of 1...

..It is probable that Ankrd1/CARP has a role in the propagation of signals initiated by myogenic regulatory factors (MRFs) during myogenesis...

..Importantly, the levels of Sf3b1 in PcG complexes were decreased in Sf3b1-heterozygous embryos. These findings suggest that Sf3b1-PcG protein interaction is essential for true PcG-mediated repression of Hox genes...

..Thus, the ;Hox code' in somitic mesoderm is the result of the distinct, graded effects of two or more Hox paralogous groups functioning in any anteroposterior location...

The Hoxa5 mutation is associated with a high perinatal mortality rate caused by a severe obstruction of the laryngotracheal airways, pulmonary dysmorphogenesis, and a decreased production of surfactant proteins...

..Together, these observations point to identical transcription factors that control motor axon guidance and soma migration and reveal the molecular hierarchy of myotopic organisation...

..Here we describe the methylation patterns of HoxA5 and HoxB5 in various tissues of fetal and adult mice and their relevance to expression...

..However, genetic crosses with a Mash2 null allele suggested that Eed was not required to maintain Mash2 imprinting, but could be required in a lineage specific fashion to suppress Mash2 expression...

..In conclusion, our data show that Moz regulates H3K9 acetylation at Hox gene loci and that RA can act independently of Moz to establish specific Hox gene expression boundaries...

..Concomitant regulation of Cyp26a1 expression, restraining retinoic acid signaling away from the posterior growth zone, may likewise play a role in timing the trunk-tail transition...

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..b>Hoxa5 belongs to the Hox gene family encoding transcription factors known for their role in skeletal patterning...

..These observations provide previously undescribed evidence for the in vivo relationship and SET domain dependence between histone methylation and DNA methylation on MLL target genes during embryonic development...

..We previously showed that the transcription factor homeobox A5 (HoxA5), which is absent in activated angiogenic endothelial cells can block angiogenesis...

..These results demonstrated significant effects of GDF11 propeptide transgene on vertebral formation, which are likely occurring through depressing GDF11 function and altered locations of Hoxa-4 and Hoxa-5 expression...

Previously, we reported a line of mice (Hoxa5SV2) that ectopically expresses HOXA5 in the developing cervical and brachial dorsal spinal cord...

..Functional redundancy between Phc2 and Phc1 leads us to hypothesize that the overall level of polyhomeotic orthologues in nuclei is a parameter that is critical in enabling the class II PcG complexes to exert their molecular functions...

Transgenic mice expressing the homeobox gene Hoxa5 under the control of Hoxb2 regulatory elements present a growth arrest during weeks two and three of postnatal development, resulting in proportionate dwarfism...

..Our results suggest that this type of protein-protein interaction may be essential for the biological activities of Hox-a5 and Scr...

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..Similar alterations in GHRHR might explain some isolated GH deficiencies in humans...

..6 and Hox3.5 during embryogenesis revealed that the relationship between relative position in the Hox3 cluster and expression domain along antero-posterior axis appears similar to that seen for members of the other Hox clusters...

..3 and Hox-4.2 genomic DNA revealed some differences in nucleotide sequences and in the deduced homeodomain amino acid sequences compared with the sequences that have been reported...

..In this study, we characterized the DNA binding properties of five representative members of the Hox family: HoxA5, HoxB4, HoxA7, HoxC8, and HoxB1...

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..All results indicate the presence of an additional ZPA at the anterior margin of limb buds in these mutants. Thus, it appears that multiple endogenous genes regulate the spatial localization of the ZPA in the developing mouse limb bud...

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..Untransformed 3T3 cells carry abundant 1.9 kb Hox 1.3 RNA, whereas the methylcholanthrene-transformed MB66 and LTK- cells or 3T3 cells transformed by the oncogenes src, fos or SV40 T antigen express only low levels...

..Finally, we have described the differential expression of these homeo-box-containing regions in various adult tissues...

..5, leading to the hypothesis that, during development, the M33 gene might play a role in defining access to retinoic acid response elements localised in the regulatory regions of several Hox genes...

..Some skeletal malformations encountered in Hoxa5 mutants are shared by the undulated (un) mice, which bear a point mutation in the Pax1 gene...

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..We have studied the expression domains of these genes in the gut both spatially and temporally...

..Such patterns of expression suggest that Hox genes play a role in the specification and maturation of lung cell lineage derivatives throughout the pseudoglandular, canalicular and terminal sac phases of lung development...

..These results indicate that the rae28 gene is involved in the regulation of Hox gene expression and segment specification during paraxial mesoderm and neural crest development...

..One member of this family, Hoxa5, displays a dynamic pattern of expression during gut development...

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..Cycloheximide and actinomycin D treatment studies suggested that the differences in RA effect on each cell type may involve the presence of a repressor that can be overcome by RA...

..4, Hox-1.3 and Hox-1.5, are expressed in the germ line but at lower levels. Further, both Hox-1.3 and Hox-1.4 produced unique, germ line-specific transcripts as compared to other adult tissues and the Day 12.5 embryo...

Mutation of murine Hoxa5 has shown that HOXA5 controls lung, gastrointestinal tract and vertebrae development. Hoxa5 is also expressed in the spinal cord, yet no central nervous system phenotype has been described in Hoxa5 knockouts...

..BMI1 complexes, along with YY1 and methylated H3-K27, were detected in upstream regulatory regions of Hoxc8 and Hoxa5. The combined data suggest a model wherein epigenetic and genetic elements cooperatively recruit and retain ..

..These experiments highlight which genes and pathways potentially affected by lack of Tbx1, and whose role may be explored further by testing for epistasis using mouse mutants...

..Our objective was to determine how pulmonary hypoplasia alters temporal, spatial, and cellular expression of Hoxa5, Hoxb4, and Hoxb6 proteins compared to normal lung development.

..We conclude that there are many homeobox genes expressed in developing rodent lung and that their mRNA levels are affected by both gestational age and RA...

..Mesodermal structures specifically affected in Hoxa5 mutant mice develop from this spatial region; therefore such elements are central to Hox5 functional expression...