Neurotropic murine retroviruses were isolated from a population of wild mice by Gardner et al. (1). These viruses have an ecotropic host range and cause, after neonatal inoculation, a noninflammatory neurodegenerative disease characterized by spongiform degeneration primarily localized to motor areas of the brain stem and spinal cord (2). The major determinant of neurovirulence has been mapped ...

Many insects exploit skylight polarization for visual compass orientation or course control. As found in crickets, the peripheral visual system (optic lobe) contains three types of polarization-sensitive neurons (POL neurons), which are tuned to different (about 60° diverging) e-vector orientations. Thus, each e-vector orientation elicits a specific combination of activities among the POL neuro...

Escherichia coli possesses five known DNA polymerases (pols). Pol III holoenzyme is the cell's main replicase, while pol I is responsible for the maturation of Okazaki fragments and filling gaps generated during nucleotide excision repair. Pols II, IV and V are significantly upregulated as part of the cell's global SOS response to DNA damage and under these conditions, may alter the fidelity of...

DNA SYNTHESIS IN CELL-FREE EXTRACTS OF A DNA POLYMERASE-DEFECTI VE MUTANT Thomas Kornberg and Malcolm L. Gefter Department of Biological Sciences Columbia University New York, New York 10027 Received August 4, 1970 Summary. A DNA-synthesizing activity has been isolated from an E. mmutant defective in DNA polvmerase. Like DNA polvmerase. the svstem requires the presence of all fbur’deoxynucleosi...

Previous findings of low levels of reverse transcriptase (RT) activity in chick cell-derived measles and mumps vaccines showed this activity to be associated with virus particles containing RNA of both subgroup E endogenous avian leukosis viruses (ALV-E) and endogenous avian viruses (EAV). These particles originate from chicken embryonic fibroblast (CEF) substrates used for propagating vaccine ...

UNLABELLED Escherichia coli's DNA polymerase IV (Pol IV/DinB), a member of the Y family of error-prone polymerases, is induced during the SOS response to DNA damage and is responsible for translesion bypass and adaptive (stress-induced) mutation. In this study, the localization of Pol IV after DNA damage was followed using fluorescent fusions. After exposure of E. coli to DNA-damaging agents, f...

Abstract Background Combination chemo-photothermal therapy appears to be one of the next generations cancer treatment. In this study hollow gold nanostars (HGNSs) and nanocages (GNCs) were synthesized stabilized with thermo-pH-sensitive thiol-end capped ABC triblock copolymer poly(acrylic acid)-b-poly( N isopropylacrylamide)-b-poly (e-caprolactone)-SH; PAA-b-PNIPAAm-b-PCL-SH (GNSs@Pol). Doxorub...

1953, the year of Watson and Crick, bore witness to a less acclaimed yet highly influential discovery. Jean Weigle demonstrated that upon infection of Escherichia coli, λ phage deactivated by UV radiation, and thus unable to form progeny, could be reactivated by irradiation of the bacterial host. Evelyn Witkin and Miroslav Radman later revealed the presence of the SOS regulon. The more than 40 ...

Stationary phase adaptive mutation in Escherichia coli is thought to be a mechanism by which mutation rates are increased during stressful conditions, increasing the possibility that fitness-enhancing mutations arise. Here we present data showing that the histone-like protein, HU, has a role in the molecular pathway by which adaptive Lac(+) mutants arise in E. coli strain FC40. Adaptive Lac(+) ...

E. coli DNA Pol II and eukaryotic Rev3 are B-family polymerases that can extend primers past a damaged or mismatched site when the high-fidelity replicative polymerases in the same family are ineffective. We report here the biochemical and structural properties of DNA Pol II that facilitate this translesion synthesis. DNA Pol II can extend primers past lesions either directly or by template ski...