George A Jacob

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Homeostatic control of volume within the alveolar spaces of the mammary gland has been proposed to involve a feedback system mediated by serotonin signaling. In this article, we describe some of the mechanisms underlying this feedback based on studies of a human normal mammary epithelial cell line (MCF10A) and mouse mammary epithelium. Mammary serotonin was(More)
We have previously shown that assembly of nucleosomes on the DNA template blocks transcription initiation by RNA polymerase II in vitro. In the studies reported here, we demonstrate that assembly of a complete RNA polymerase II preinitiation complex before nucleosome assembly results in nucleosomal templates which support initiation in vitro as efficiently(More)
We have investigated the formation of the first phosphodiester bond by RNA polymerase II in vitro. The template was a cloned DNA bearing the adenovirus 2 major late promoter; transcription factors and RNA polymerase II were provided by a HeLa cell nuclear extract. Dinucleotide primers and single nucleoside triphosphates were used as substrates. We found(More)
We have measured the ability of three TATA box promoters, adenovirus 2 major late (Ad 2 ML), Ad 2 ML with a point mutation in the TATA box, and mouse beta-globin, to support abortive and productive RNA synthesis in vitro. We have also measured the ability of these promoters to direct the assembly of preinitiation complexes using a nuclease protection assay.(More)
We have shown that accurate initiation of productive RNA synthesis in vitro at the adenovirus 2 major late promoter is accompanied by abortive initiation of very short transcripts (Luse, D. S., and Jacob, G. A. (1987) J. Biol. Chem. 262, 14990-14997). We made a set of sequence variants of this promoter, using every possible base at position -28 (in the TATA(More)
We previously demonstrated that RNA polymerase II promoters may be limited in strength not only at the step of transcription complex assembly, but also at initiation or promoter clearance. Here we report on experiments designed to test the possibility that steps following transcription complex assembly might be stimulated by transcriptional activators.(More)
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