L cells lacking thymidine kinase (TK) activity (Ltk-cells) have been stably transformed to a TK-positive phenotype by infection with ultraviolet-irradiated herpes simplex virus (HSV-UV). The highest frequency of the Ltkto Ltk+ transformation observed in these experiments was approximately 10-3, whereas no measurable transformation was observed (less than 10-8) in the absence of HSV-UV infection. Cell lines of HSV-transformed Ltk+ cell lines contain 7 to 24 times as much TK activity as do the parental Ltk-cells, and they have been maintained in culture for a period exceeding 8 months. The kinetics of thermal inactivation of the TK activity derived from an Ltk+ HSV-transformed cell line and the TK activity from Ltkc cells lytically infected with infectious HSV are similar. Both of these TK activities are much more thermolabile than the TK activity present in wild-type L cells. A mutant strain of HSV which does not induce TK activity during lytic infection does not cause the Ltkto Ltk+ transformation. These data suggest that either an HSV TK gene has been transferred to Ltk-cells or that an HSV gene product has caused the expression of a previously repressed cellular enzyme.
Elite universities are credited as launch points for the widest variety of meaningful careers. Yet, year after year at the most selective universities, nearly half the graduating seniors head to a surprisingly narrow band of professional options. Over the past few decades, this has largely been into the finance and consulting sectors, but increasingly it also includes high-tech firms. This study uses a cultural-organizational lens to show how student cultures and campus structures steer large portions of anxious and uncertain students into high-wealth, high-status occupational sectors. Interviewing 56 students and recent alumni at Harvard and Stanford Universities, we found that the majority of our respondents experienced confusion about career paths when first arriving at college but quickly learned what were considered to be the most prestigious options. On-campus corporate recruitment for finance, consulting, and high-tech jobs functioned as a significant driver of student perceptions of status; career prestige systems built up among peers exacerbated the funneling effect into these jobs. From these processes, students learned to draw boundaries between ''high-status'' and ''ordinary'' jobs. Our findings demonstrate how status processes on college campuses are central in generating preferences for the uppermost positions in the occupational structure and that elite campus environments have a large, independent role in the production and reproduction of social inequality.
Transformation of mouse cells (Ltk
−
) and human cells (HeLa Bu) from a thymidine kinase (TK)-minus to a TK
+
phenotype (herpes simplex virus [HSV]-transformed cells) has been induced by infection with ultraviolet-irradiated HSV type 2 (HSV-2), as well as by HSV type 1 (HSV-1). Medium containing methotrexate, thymidine, adenine, guanosine, and glycine was used to select for cells able to utilize exogenous thymidine. We have determined the kinetics of thermal inactivation of TK from cells lytically infected with HSV-1 or HSV-2 and from HSV-1- and HSV-2-transformed cells. Three hours of incubation at 41 C produces a 20-fold decrease in the TK activity of cell extracts from HSV-2-transformed cells and Ltk
−
cells lytically infected with HSV-2. The same conditions produce only a twofold decrease in the TK activities from HSV-1-transformed cells and cells lytically infected with HSV-1. This finding supports the hypothesis that an HSV structural gene coding for TK has been incorporated in the HSV-transformed cells.
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