Ectopic expression of Hoxa-1 in the zebrafish alters the fate of the mandibular arch neural crest and phenocopies a retinoic acid-induced phenotype

TY - JOUR

T1 - Ectopic expression of Hoxa-1 in the zebrafish alters the fate of the mandibular arch neural crest and phenocopies a retinoic acid-induced phenotype

AU - Alexandre, D

AU - Clarke, J D

AU - Oxtoby, E

AU - Yan, Y L

AU - Jowett, T

AU - Holder, N

PY - 1996/3

Y1 - 1996/3

N2 - Considerable evidence has demonstrated that retinoic acid influences the formation of the primary body axis in vertebrates and that this may occur through the regulation of Hox gene expression. In this study, we show that the phenotype induced by exogenous retinoic acid in the zebrafish can also be generated by the overexpression of Hoxa-1 following injection of synthetic RNA into the fertilised egg. The isolation, sequence and expression pattern of the zebrafish Hoxa-1 gene is described. We show that exogenously applied retinoic acid causes the ectopic accumulation of Hoxa-1 message during gastrulation in the hypoblast in the head region. Overexpression of Hoxa-1 following injection of RNA causes abnormal growth of the anterior hindbrain, duplication of Mauthner neurons in rhombomere (r) 2 and fate changes of r2 mesenchymal and neurogenic neural crest. These results are discussed in terms of the role of Hoxa-1 in controlling anterior hindbrain patterning and the relationship between expression of Hoxa-1 and retinoic acid.

AB - Considerable evidence has demonstrated that retinoic acid influences the formation of the primary body axis in vertebrates and that this may occur through the regulation of Hox gene expression. In this study, we show that the phenotype induced by exogenous retinoic acid in the zebrafish can also be generated by the overexpression of Hoxa-1 following injection of synthetic RNA into the fertilised egg. The isolation, sequence and expression pattern of the zebrafish Hoxa-1 gene is described. We show that exogenously applied retinoic acid causes the ectopic accumulation of Hoxa-1 message during gastrulation in the hypoblast in the head region. Overexpression of Hoxa-1 following injection of RNA causes abnormal growth of the anterior hindbrain, duplication of Mauthner neurons in rhombomere (r) 2 and fate changes of r2 mesenchymal and neurogenic neural crest. These results are discussed in terms of the role of Hoxa-1 in controlling anterior hindbrain patterning and the relationship between expression of Hoxa-1 and retinoic acid.

KW - Animals

KW - Rhombencephalon

KW - Homeodomain Proteins

KW - Neural Crest

KW - Amino Acid Sequence

KW - Zebrafish

KW - Cloning, Molecular

KW - Mandible

KW - Phenotype

KW - RNA, Messenger

KW - Genes, Homeobox

KW - Base Sequence

KW - Sequence Alignment

KW - Molecular Sequence Data

KW - Tretinoin

KW - Sequence Homology, Amino Acid

KW - Trans-Activators

KW - Gene Expression Regulation, Developmental

M3 - Article

C2 - 8631251

SN - 0950-1991

VL - 122

SP - 735

EP - 746

JO - Development (Cambridge): for advances in developmental biology and stem cells

JF - Development (Cambridge): for advances in developmental biology and stem cells

IS - 3

ER -