Cloning and analysis of three new homeobox genes from the nematode Caenorhabditis elegans.
Three homeobox-containing genes from the nematode Caenorhabditis elegans are described. Two of them (ceh-11 and ceh-12) were isolated from a genomic library by hybridization at low stringency with the Ascaris lumbricoides homeobox AHB-1. The first clone contains a homeobox defining a new class of homeoboxes (ceh-11). This gene maps on the third chromosome of C. elegans, at the same locus as egl-5, a gene already known to be essential for the determination of specific neurons. In the second clone, sequence analysis revealed the existence of the third helix of a putative homeobox (ceh-12) which is interrupted by an intron located upstream of the codon for the amino acid 45 of the homeodomain. Using the ceh-11 homeobox as a probe, a third homeobox (ceh-13) was isolated from a cDNA library. As ceh-13 belongs to the labial class of homeoboxes, we conclude that, at the time when the nematode lineage diverged from the myriapod-insect and the vertebrate lineages, the duplication which led to the Antp and the labial families of homeoboxes had already taken place.
Schaller
D
D
Institute of Zoology, University of Fribourg, Pérolles, Switzerland.
Wittmann
C
C
Spicher
A
A
Müller
F
F
Tobler
H
H
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002107:Caenorhabditis / Q000235:genetics*; D029742:Caenorhabditis elegans Proteins; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics / Q000302:isolation & purification; D005801:Genes, Homeobox; D008969:Molecular Sequence Data; D015183:Restriction Mapping; D014157:Transcription Factors
C518285:CEH-12 protein, C elegans; D029742:Caenorhabditis elegans Proteins; D014157:Transcription Factors; D004247:DNA