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：1993
卷号：90
期号：4
页码：1450-1454
DOI：10.1073/pnas.90.4.1450
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The mechanisms determining the functional specificity of Drosophila homeodomain proteins are largely unknown. Here, the role of DNA-binding specificity for the in vivo function of the homeodomain protein fushi tarazu (ftz) is analyzed. We find that specific DNA binding is an important but not sufficient determinant of the functional specificity of ftz in vivo: The ftz DNA-binding specificity mutant ftzQ50K retains partial ftz wild-type activity in gene activation and phenotypic rescue assays. Furthermore, specificity mutations in a ftz-in vivo binding site only partially reduce enhancer activity as compared to null mutations of this site. Despite bicoid-like DNA-binding specificity ftzQ50K does not activate natural or artificial bcd target genes in the realms of ftz. These results are discussed in the light of recent observations on the mechanism of action of the yeast homeodomain protein alpha 2.
