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McClintock JM
,
Jozefowicz C
,
Assimacopoulos S
,
Grove EA
,
Louvi A
,
Prince VE
.
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The previously described expression patterns of zebrafish and mouse Hoxa1 genes are seemingly very disparate, with mouse Hoxa1 expressed in the gastrula stage hindbrain and the orthologous zebrafish hoxa1a gene expressed in cell clusters within the ventralforebrain and midbrain. To investigate the evolution of Hox gene deployment within the vertebrate CNS, we have performed a comparative expression analysis of Hoxa1 orthologs in a range of vertebrate species, comprising representatives from the two major lineages of vertebrates (actinopterygians and sarcopterygians). We find that fore/midbrain expression of hoxa1a is conserved within the teleosts, as it is shared by the ostariophysan teleost zebrafish (Danio rerio) and the distantly related acanthopterygian teleost medaka (Oryzias latipes). Furthermore, we find that in addition to the described gastrula stage hindbrain expression of mouse Hoxa1, there is a previously unreported neurula stage expression domain, again located more anteriorly at the ventral fore/midbrain boundary. A two-phase expression profile in early hindbrain and later fore/midbrain is shared by the other tetrapod model organisms chick and Xenopus. We show that the anteriorHoxa1 expression domain is localized to the anterior terminus of the medial longitudinal fasciculus (MLF) in mouse, chick, and zebrafish. These findings suggest that anterior expression of Hoxa1 is a primitive characteristic that is shared by the two major vertebrate lineages. We conclude that Hox gene expression within the vertebrate CNS is not confined exclusively to the segmented hindbrain and spinal cord, but rather that a presumptive fore/midbrain expression domain arose early in vertebrate origins and has been conserved for at least 400 million years.
Amores,
Zebrafish hox clusters and vertebrate genome evolution.
1998, Pubmed
Amores,
Zebrafish hox clusters and vertebrate genome evolution.
1998,
Pubmed
Baron,
Hox-1.6: a mouse homeo-box-containing gene member of the Hox-1 complex.
1987,
Pubmed
Belting,
Multiple phases of expression and regulation of mouse Hoxc8 during early embryogenesis.
,
Pubmed
Chiu,
Molecular evolution of the HoxA cluster in the three major gnathostome lineages.
2002,
Pubmed
Dupé,
Hindbrain patterning involves graded responses to retinoic acid signalling.
2001,
Pubmed
Force,
Hox cluster organization in the jawless vertebrate Petromyzon marinus.
2002,
Pubmed
Force,
Preservation of duplicate genes by complementary, degenerative mutations.
1999,
Pubmed
Frasch,
Evolutionary-conserved enhancers direct region-specific expression of the murine Hoxa-1 and Hoxa-2 loci in both mice and Drosophila.
1995,
Pubmed
Frohman,
Isolation and analysis of embryonic expression of Hox-4.9, a member of the murine labial-like gene family.
1992,
Pubmed
Gaufo,
Hoxb1 controls effectors of sonic hedgehog and Mash1 signaling pathways.
2000,
Pubmed
Gibson,
Genetic redundancy in vertebrates: polyploidy and persistence of genes encoding multidomain proteins.
1998,
Pubmed
Greer,
Hoxb8 is required for normal grooming behavior in mice.
2002,
Pubmed
Grove,
The hem of the embryonic cerebral cortex is defined by the expression of multiple Wnt genes and is compromised in Gli3-deficient mice.
1998,
Pubmed
,
Xenbase
HAMBURGER,
A series of normal stages in the development of the chick embryo.
1951,
Pubmed
Hemmati-Brivanlou,
Localization of specific mRNAs in Xenopus embryos by whole-mount in situ hybridization.
1990,
Pubmed
,
Xenbase
Hunter,
Zebrafish hox paralogue group 2 genes function redundantly as selector genes to pattern the second pharyngeal arch.
2002,
Pubmed
Irvine,
Genomic analysis of Hox clusters in the sea lamprey Petromyzon marinus.
2002,
Pubmed
Jackman,
Coincident iterated gene expression in the amphioxus neural tube.
2002,
Pubmed
Katsuyama,
Expression of the labial group Hox gene HrHox-1 and its alteration induced by retinoic acid in development of the ascidian Halocynthia roretzi.
1995,
Pubmed
Kim,
Hox cluster genomics in the horn shark, Heterodontus francisci.
2000,
Pubmed
Kolm,
Regulation of the Xenopus labial homeodomain genes, HoxA1 and HoxD1: activation by retinoids and peptide growth factors.
1995,
Pubmed
,
Xenbase
Langston,
Retinoic acid-responsive enhancers located 3' of the Hox A and Hox B homeobox gene clusters. Functional analysis.
1997,
Pubmed
Langston,
Identification of a retinoic acid responsive enhancer 3' of the murine homeobox gene Hox-1.6.
1992,
Pubmed
Loosli,
Six3, a medaka homologue of the Drosophila homeobox gene sine oculis is expressed in the anterior embryonic shield and the developing eye.
1998,
Pubmed
Macdonald,
Regulatory gene expression boundaries demarcate sites of neuronal differentiation in the embryonic zebrafish forebrain.
1994,
Pubmed
Mastick,
Initial organization of neurons and tracts in the embryonic mouse fore- and midbrain.
1996,
Pubmed
McClintock,
Knockdown of duplicated zebrafish hoxb1 genes reveals distinct roles in hindbrain patterning and a novel mechanism of duplicate gene retention.
2002,
Pubmed
McClintock,
Consequences of Hox gene duplication in the vertebrates: an investigation of the zebrafish Hox paralogue group 1 genes.
2001,
Pubmed
Murphy,
Expression of the mouse labial-like homeobox-containing genes, Hox 2.9 and Hox 1.6, during segmentation of the hindbrain.
1991,
Pubmed
Naruse,
A detailed linkage map of medaka, Oryzias latipes: comparative genomics and genome evolution.
2000,
Pubmed
Postlethwait,
Vertebrate genome evolution and the zebrafish gene map.
1998,
Pubmed
Prince,
Splitting pairs: the diverging fates of duplicated genes.
2002,
Pubmed
Prince,
Zebrafish hox genes: expression in the hindbrain region of wild-type and mutants of the segmentation gene, valentino.
1998,
Pubmed
Prince,
The Hox Paradox: More complex(es) than imagined.
2002,
Pubmed
Sakach,
Localization of the HoxB5 protein in the developing CNS of late gestational mouse embryos.
1996,
Pubmed
Shih,
Expression of zebrafish Hoxa1a in neuronal cells of the midbrain and anterior hindbrain.
2001,
Pubmed
Sive,
Retinoic acid perturbs the expression of Xhox.lab genes and alters mesodermal determination in Xenopus laevis.
1991,
Pubmed
,
Xenbase
Wada,
Colinear and segmental expression of amphioxus Hox genes.
1999,
Pubmed
