RESUMEN
We report here a method for the in vivo dissection of the regulatory region of a gene in the Drosophila genome. Our system includes (i) the reporter genes lacZ and white to detect transcriptional enhancer and silencer activities in a target gene, (ii) an efficient way to induce integration of gypsy elements in the genome, and (iii) unidirectional blocking of regulatory activities by the gypsy element, which is dependent on the su(Hw) protein. The optomotor-blind (omb) gene was analyzed. In the omb(P1) line, a P[lacW] construct is inserted about 1.4 kb upstream of the omb transcription start site. The lacZ reporter gene within P[lacW] exhibits the same expression pattern as omb. The white reporter gene is expressed in a "bipolar" pattern. We induced high frequency gypsy mobilization in omb(P1) and identified two lines (D11 and D13-1) with altered eye pigmentation pattern, which is dependent on su(Hw) activity. A gypsy element was found inserted in the first intron of omb in D13-1 and in P[lacW] in D11. These results indicate that it is the blocking of regulatory activities by gypsy that caused the changes in the white reporter gene expression. The effect of these gypsy insertions on the expression patterns allowed us to predict several aspects of the organization of the regulatory elements in the omb locus.
Asunto(s)
Proteínas de Unión al ADN/genética , Proteínas de Drosophila , Drosophila/genética , Genes de Insecto , Genes Reguladores , Proteínas del Tejido Nervioso/genética , Retroelementos/genética , Proteínas de Dominio T Box , AnimalesRESUMEN
Congenital Horner's syndrome is an infrequent illness caused by a lesion of the cervical sympathetic nerve fiber. It's clinical features are facial anhidrosis, ptosis, miosis, and hypochromia iridis of the affected side. The subject of this report, a full-term male newborn, had had a smooth birth process but was found on the second day of life to have narrowing of the palpebral fissure and absence of facial flushing on the right side when he cried. Ophthalmologic examination revealed a smaller right pupil. The above abnormalities proved to result from a post-ganglionic lesion, after pharmacologic test. Roentgenograms of the skull, chest and cervical spine were normal, and a computed tomography scan of the cervical spine showed no abnormalities. The diagnosis was of congenital Horner's syndrome. Since no congenital Horner's syndrome to the newborn period could be found in previous literature, this report is presented.