in the spring of 1995, i attended a session at the organization of American Historians conference at the Washington Hilton, which focused on the state of political history. When i walked toward the conference room i expected to find a small crowd, and one with little hope for the future. At the time, the political history field seemed bleak. senior practitioners, who, for at least two decades, ...

We compared the neurokinin 1 receptor (NK(1)R) antagonists aprepitant, CP-99994 [(2S,3S)-3-(2-methoxybenzylamino)-2-phenylpiperidine], and ZD6021 [3-cyano-N-((2S)-2-(3,4-dichlorophenyl)-4-[4-[2-(methyl-(S)-sulfinyl)phenyl]piperidino]butyl)-N-methyl]napthamide]] with respect to receptor interactions and duration of efficacy in vivo. In Ca(2+) mobilization assays (fluorometric imaging plate reade...

properties of influenza viruses 2 Jaclyn L. Myers, Katherine S. Wetzel, Susanne L. Linderman, Yang Li, Colleen 3 B. Sullivan, Scott E. Hensley 4 5 Wistar Institute, Philadelphia, PA 19104, USA 6 Department of Microbiology, University of Pennsylvania, Philadelphia, PA 19104, USA 7 Institute for Immunology, University of Pennsylvania, Philadelphia, PA 19104, USA 8 These authors contributed equall...

The single-stranded DNA-binding protein, Replication Protein A (RPA), is a heterotrimeric complex with subunits of 70, 32 and 14 kDa involved in DNA metabolism. RPA may be a target for cellular regulation; the 32 kDa subunit (RPA32) is phosphorylated by several cellular kinases including the DNA-dependent protein kinase (DNA-PK). We have purified a mutant hRPA complex lacking amino acids 1-33 o...

We have analyzed SV40 specific RNA sequences which are associated with purified viral chromatin. Three discrete size classes of large unprocessed transcripts were identified: 4.8, 3.6 and 3.0 kb. Furthermore, two polyadenylated species of 2.6 and 1.6 kb were found, the latter of which representing mature 16 S mRNA. S1 analysis revealed both the presence of spliced and unspliced RNA sequences in...

The interaction between simian virus 40(SV40)-induced endocytotic vacuoles and the nuclear membrane was investigated using cationized ferritin (CF) and concanavalin A (Con A) as cell membrane markers. These markers bound to the cell surfaces of CV-1 cells together with SV40 at 4 degrees C. Following incubation of these modified cells at 37 degrees C in serum-free medium, the cell membranes show...

Mammalian replication protein A (RPA) undergoes DNA damage-dependent phosphorylation at numerous sites on the N terminus of the RPA2 subunit. To understand the functional significance of RPA phosphorylation, we expressed RPA2 variants in which the phosphorylation sites were converted to aspartate (RPA2(D)) or alanine (RPA2(A)). Although RPA2(D) was incorporated into RPA heterotrimers and suppor...

The carcinogen, 7r,8t-dihydroxy-9t,10t-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene, and a number of its noncarcinogenic derivatives form a reversible physical complex with DNA in vitro. The absorbance spectrum of the hydrocarbon in the complex shifts approximately 10 nm to the red. Fluorescence from the physically bound hydrocarbon is significantly quenched, and binding levels are decreased by the ...

We have constructed 14 independent point mutations in the conserved AAUAAA element of the SV40 late polyadenylation signal in order to study the recognition and function of alternative polyadenylation signals. A variant RNA containing an AUUAAA was polyadenylated at 20% the level of wild-type substrate RNA, while all other derivatives tested were not functional in vitro. The AUUAAA variant RNA ...

Simian virus 40 (SV40) mutants dl1066 and dl1140 contain deletions within the region encoding the carboxyl terminus of the large tumor (T) antigen. Although these mutations have little effect on the efficiency of viral DNA replication, they decrease the yield of infectious virus particles by 3-4 orders of magnitude [Pipas, J. (1985) J. Virol. 54, 569-575]. Here we show that the level of late RN...