Graded effect of tailless on posterior gut development: molecular basis of an allelic series of a nuclear receptor gene.
By marking cells of early gastrula stage embryos, we showed that in embryos mutant for a strong tll allele the fate map is shifted posteriorly and the hindgut anlage is deleted. We therefore used aspects of hindgut development to characterize the phenotype of new and previously described tll alleles. In embryos mutant for the various alleles, relative levels of blastoderm expression of Trg (T-related gene, required to establish the hindgut) and of mature hindgut size were determined; the results of these assays correlated with each other. Of the alleles that map to the sequence encoding the Tailless nuclear receptor protein, all (four) affect the zinc fingers of the DNA binding domain; surprisingly, substitutions of highly conserved residues allow a range of activities as detected by our bioassays.
Diaz
R J
RJ
Department of Molecular, Cell and Developmental Biology, UCLA 90095-1606, USA.
Harbecke
R
R
Singer
J B
JB
Pignoni
F
F
Janning
W
W
Lengyel
J A
JA
D000483:Alleles; D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D001756:Blastoderm / Q000378:metabolism; D019070:Cell Lineage; D004247:DNA / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000502:physiology*; D029721:Drosophila Proteins; D004331:Drosophila melanogaster / Q000196:embryology / Q000235:genetics*; D004625:Embryo, Nonmammalian / Q000378:metabolism / Q000648:ultrastructure; D005775:Gastrula / Q000166:cytology / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental; D017344:Genes, Insect; D005804:Genes, Lethal; D007413:Intestinal Mucosa / Q000378:metabolism; D007422:Intestines / Q000196:embryology*; D008969:Molecular Sequence Data; D010641:Phenotype; D017354:Point Mutation; D012097:Repressor Proteins / Q000235:genetics / Q000502:physiology*; D017384:Sequence Deletion; D016335:Zinc Fingers / Q000235:genetics / Q000502:physiology
D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D012097:Repressor Proteins; C074090:TLL protein, Drosophila; D004247:DNA