期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1991
卷号：88
期号：3
页码：810-814
DOI：10.1073/pnas.88.3.810
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Loss of maternal function of the tube gene disrupts a signaling pathway required for pattern formation in Drosophila, causing cells throughout the embryo to adopt the fate normally reserved for those at the dorsal surface. Here we demonstrate that tube mutations also have a zygotic effect on pupal morphology and that this phenotype is shared by mutations in Toll and pelle, two genes with apparent intracellular roles in determining dorsoventral polarity. We then describe the isolation of a functionally full-length tube cDNA identified in a phenotypic rescue assay. The tube mRNA is expressed maximally early in embryogenesis and again late in larval development, corresponding to required periods of tube activity as defined by distinct maternal and zygotic loss-of-function phenotypes in tube mutants. Sequence analysis of the cDNA indicates that the tube protein contains five copies of an eight-residue motif and shares no significant sequence similarity with known proteins. These results suggest that tube represents a class of protein active in signal transduction at two stages of development.
