Homologs of the Caenorhabditis elegans masculinizing gene her-1 in C. briggsae and the filarial parasite Brugia malayi.
The masculinizing gene her-1 in Caenorhabditis elegans (Ce-her-1) encodes a novel protein, HER-1A, which is required for male development. To identify conserved elements in her-1 we have cloned and characterized two homologous nematode genes: one by synteny from the closely related free-living species C. briggsae (Cb-her-1) and the other, starting with a fortuitously identified expressed sequence tag, from the distantly related parasite Brugia malayi (Bm-her-1). The overall sequence identities of the predicted gene products with Ce-HER-1A are only 57% for Cb-HER-1, which is considerably lower than has been found for most homologous briggsae genes, and 35% for Bm-HER-1. However, conserved residues are found throughout both proteins, and like Ce-HER-1A, both have putative N-terminal signal sequences. Ce-her-1 produces a larger masculinizing transcript (her-1a) and a smaller transcript of unknown function (her-1b); both are present essentially only in males. By contrast, Cb-her-1 appears to produce only one transcript, corresponding to her-1a; it is enriched in males but present also in hermaphrodites. Injection of dsRNA transcribed from Cb-her-1 into C. briggsae hermaphrodites (RNA interference) caused XO animals to develop into partially fertile hermaphrodites. Introducing a Cb-her-1 construct as a transgene under control of the C. elegans unc-54 myosin heavy chain promoter caused strong masculinization of both C. briggsae and C. elegans hermaphrodites. Introduction of a similar Bm-her-1 construct into C. elegans caused only very weak, if any, masculinization. We conclude that in spite of considerable divergence the Cb gene is likely to be a functional ortholog of Ce-her-1, while the function of the distantly related Bm gene remains uncertain.
Streit
A
A
Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder, Colorado 80309-0347, USA.
Li
W
W
Robertson
B
B
Schein
J
J
Kamal
I H
IH
Marra
M
M
Wood
W B
WB
D000595:Amino Acid Sequence; D000818:Animals; D030801:Animals, Genetically Modified; D017178:Brugia malayi / Q000235:genetics*; D002107:Caenorhabditis / Q000235:genetics*; D017173:Caenorhabditis elegans / Q000235:genetics*; D029742:Caenorhabditis elegans Proteins; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D012734:Disorders of Sex Development / Q000235:genetics*; D019143:Evolution, Molecular; D017238:Genes, Helminth; D015801:Helminth Proteins / Q000235:genetics* / Q000502:physiology; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000502:physiology; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid; D019849:Sex Determination Processes; D013045:Species Specificity
D029742:Caenorhabditis elegans Proteins; D018076:DNA, Complementary; D015801:Helminth Proteins; D011993:Recombinant Fusion Proteins; C079744:her-1 protein, C elegans