Genomic sequence and embryonic expression of the zebrafish homeobox gene hox-3.4.
We have analyzed the genomic DNA sequence and embryonic expression pattern of the zebrafish hox-3.4 gene. Two exons, encoding a protein with a total size of 232 amino acids, were identified within a 3.5 kbp genomic region. Besides the homeodomain, which is identical to that of the human HOX3D and mouse Hox-3.4 genes, the first 58 residues of the N-terminal domain in the predicted Hox-3.4 protein share 48% sequence identity with the gene product of the human cognate. Some of the N-terminal sequence elements are also conserved relative to the two other members of the Hox-1.3/Hox-2.1/Hox-3.4 paralogy group. In addition, the paralogous genes share a significant degree of sequence identity in non-coding regions. This conservation is particularly evident in the promoter regions of the cognates hox-3.4, Hox-3.4, and HOX3D, where a 180 bp TATA-box-containing element with a 60% identity is located. This is in agreement with the previous finding that the HOX3D promoter region contains response elements for other Hox proteins and retinoids. Also with respect to embryonic expression, the zebrafish hox-3.4 gene is very similar to its mammalian counterparts. Within the central nervous system of 16, 24, and 48 h embryos, hox-3.4 transcripts were detected throughout most of the spinal cord from a boundary at the posterior end of the hindbrain. In 16 h embryos the hox-3.4 gene is also active within a restricted region of the tailbud.
Ericson
J U
JU
Department of Molecular Genetics, University of Tromsø, Norway.
Krauss
S
S
Fjose
A
A
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002490:Central Nervous System / Q000196:embryology / Q000378:metabolism; D003001:Cloning, Molecular; D017124:Conserved Sequence; D004268:DNA-Binding Proteins / Q000096:biosynthesis / Q000235:genetics*; D004625:Embryo, Nonmammalian / Q000502:physiology; D005091:Exons; D005801:Genes, Homeobox; D018398:Homeodomain Proteins; D006801:Humans; D017403:In Situ Hybridization; D007438:Introns; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D015183:Restriction Mapping; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid; D013116:Spinal Cord / Q000196:embryology / Q000378:metabolism; D016385:TATA Box; D014158:Transcription, Genetic; D015027:Zebrafish / Q000235:genetics*; D029961:Zebrafish Proteins
D004268:DNA-Binding Proteins; D018398:Homeodomain Proteins; D029961:Zebrafish Proteins; C083560:hoxc5a protein, zebrafish