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：1998
卷号：95
期号：14
页码：8316-8321
DOI：10.1073/pnas.95.14.8316
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：DNA fragments -0.57, -2.2, -2.9, -5.3, and -8.4 kb in length from the upstream regulatory region of the vnd/NK-2 gene were cloned in the 5'-flanking region of a {beta}-galactosidase ({beta}-gal) reporter gene in the P-element pCaSpeR-AUG-{beta}-gal, and the effects of the DNA on the pattern and time of expression of {beta}-gal were determined in transgenic embryos. Embryos from 11 lines transformed with -8.4 kb of vnd/NK-2 regulatory DNA expressed {beta}-gal patterns that closely resemble those of vnd/NK-2. In embryos from four lines transformed with -5.3 kb of vnd/NK-2 DNA, {beta}-gal was found in the normal vnd/NK-2 pattern in the nerve cord but not in part of the cephalic region. {beta}-Gal patterns in embryos from transgenic lines containing -0.57, -2.2, or -2.9 kb of vnd/NK-2 DNA did not resemble vnd/NK-2. Null vnd/NK-2 mutant embryos containing the homozygous P-element p[-8.4 to +0.34 {beta}-gal] expressed little {beta}-gal in contrast to siblings with a wild-type vnd/NK-2 gene. We conclude that (i) the 8.4-kb DNA fragment from the vnd/NK-2 gene contains the nucleotide sequences required to generate the normal pattern of vnd/NK-2 gene expression, sequences that may be involved in the switch between neuroblast vs. epidermoblast pathways of development, (ii) the 5'-flanking region of the vnd/NK-2 gene between -5.3 and -8.4 kb is required for vnd/NK-2 gene expression in the most dorsoanterior part of the cephalic region, and (iii) vnd/NK-2 protein is required, directly or indirectly, for maintenance of vnd/NK-2 gene expression.
