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Deliberative pedagogy encourages productive science communication and learning through engagement and discussion of socio-scientific issues (SSI). This article examines a two-day deliberation module on gene editing that took place in an introductory nonmajors biology course, furthering research on integrating deliberative discussion into the biology classroom. The results demonstrate the benefits of a single, episodic deliberation in the classroom, which can positively encourage active discussion and critical awareness of connections between biology and real-world issues, thus contributing to the development of scientific citizenship. Additionally, the findings show that gene editing is an apt SSI topic for the deliberative process because it encourages productive communication practices of scientific citizenship, including discussion, perspective taking, questioning, and consideration of different types of evidence when coming to a decision.

Hepatitis C virus (HCV) induces microtubule aggregates in infected hepatocytes. To determine if cytoskeletal elements are important for HCV RNA synthesis, we examined the effect of cytoskeleton inhibitors on HCV replicon transcription in Huh7 cells. The data demonstrate that HCV replication complex-mediated RNA synthesis requires microtubule and actin polymerization.

The coronavirus mouse hepatitis virus (MHV) directs the synthesis of viral RNA on discrete membranous complexes that are distributed throughout the cell cytoplasm. These putative replication complexes are composed of intimately associated but biochemically distinct membrane populations, each of which contains proteins processed from the replicase (gene 1) polyprotein. Specifically, one membrane population contains the gene 1 proteins p65 and p1a-22, while the other contains the gene 1 proteins p28 and helicase, as well as the structural nucleocapsid (N) protein and newly synthesized viral RNA. In this study, immunofluorescence confocal microscopy was used to define the relationship of the membrane populations comprising the putative replication complexes at different times of infection in MHV-A59-infected delayed brain tumor cells. At 5.5 h postinfection (p.i.) the membranes containing N and helicase colocalized with the membranes containing p1a-22/p65 at foci distinct from sites of M accumulation. By 8 to 12 h p.i., however, the membranes containing helicase and N had a predominantly perinuclear distribution and colocalized with M. In contrast, the p1a-22/p65-containing membranes retained a peripheral, punctate distribution at all times of infection and did not colocalize with M. By late times of infection, helicase, N, and M each also colocalized with ERGIC p53, a specific marker for the endoplasmic reticulum-Golgi-intermediate compartment. These data demonstrated that the putative replication complexes separated into component membranes that relocalized during the course of infection. These results suggest that the membrane populations within the MHV replication complex serve distinct functions both in RNA synthesis and in delivery of replication products to sites of virus assembly., (Copyright 2001 Academic Press.)

The replicase gene (gene 1) of the coronavirus mouse hepatitis virus (MHV) encodes two co-amino-terminal polyproteins presumed to incorporate all the virus-encoded proteins necessary for viral RNA synthesis. The polyproteins are cotranslationally processed by viral proteinases into at least 15 mature proteins, including four predicted cleavage products of less than 25 kDa that together would comprise the final 59 kDa of protein translated from open reading frame 1a. Monospecific antibodies directed against the four distinct domains detected proteins of 10, 12, and 15 kDa (p1a-10, p1a-12, and p1a-15) in MHV-A59-infected DBT cells, in addition to a previously identified 22-kDa protein (p1a-22). When infected cells were probed by immunofluorescence laser confocal microscopy, p1a-10, -22, -12, and -15 were detected in discrete foci that were prominent in the perinuclear region but were widely distributed throughout the cytoplasm as well. Dual-labeling experiments demonstrated colocalization of the majority of p1a-22 in replication complexes with the helicase, nucleocapsid, and 3C-like proteinase, as well as with p1a-10, -12, and -15. p1a-22 was also detected in separate foci adjacent to the replication complexes. The majority of complexes containing the gene 1 proteins were distinct from sites of accumulation of the M assembly protein. However, in perinuclear regions the gene 1 proteins and nucleocapsid were intercalated with sites of M protein localization. These results demonstrate that the complexes known to be involved in RNA synthesis contain multiple gene 1 proteins and are closely associated with structural proteins at presumed sites of virion assembly.