Accumulation of unfolded proteins in the endoplasmic reticulum (ER) causes ER stress and results in the activation of the unfolded protein response (UPR), which aims at restoring ER homeostasis. However, when the stress is too severe the UPR switches from being a pro-survival response to a pro-death one, and the molecular mechanisms underlying ER stress-mediated death have remained incompletely understood. In this study, we identified receptor interacting protein kinase 1 (RIPK1)-a kinase at the crossroad between life and death downstream of various receptors-as a new regulator of ER stress-induced death. We found that Ripk1-deficient MEFs are protected from apoptosis induced by ER stressors, which is reflected by reduced caspase activation and PARP processing. Interestingly, the pro-apoptotic role of Ripk1 is independent of its kinase activity, is not regulated by its cIAP1/2-mediated ubiquitylation, and does not rely on the direct regulation of JNK or CHOP, two reportedly main players in ER stress-induced death. Instead, we found that ER stress-induced apoptosis in these cells relies on death receptor-independent activation of caspase-8, and identified Ripk1 upstream of caspase-8. However, in contrast to RIPK1-dependent apoptosis downstream of TNFR1, we did not find Ripk1 associated with caspase-8 in a death-inducing complex upon unresolved ER stress. Our data rather suggest that RIPK1 indirectly regulates caspase-8 activation, in part via interaction with the ER stress sensor inositol-requiring protein 1 (IRE1).

Journalists have traditionally focused on a small range of elite sources. Far less attention went to ordinary or common people, resulting in little visibility for that community in news output. However, bottom-up Web 2.0 technologies have given common people new communication tools, allowing them to disperse information autonomously. This has made traditional news media aware of a public desire for bottom-up participation in the news production process. Accordingly, some news media have begun to offer their own participation features. Bearing this context in mind, we address the question whether Web 2.0 has helped increase the visibility and importance of the common people in daily news output. Via a content analysis of five Flemish newspapers, the current representation of ordinary citizens is compared to a decade ago, before the appearance Web 2.0. The analysis shows that citizens appear more prominently in the news nowadays.

Much attention has been paid to audience participation in online journalism in recent years. This article contributes to that ongoing discussion by focusing on the previously largely overlooked macro level. It compares participatory journalism on German and Flemish national newspapers’ Web sites with a threefold aim: a) discussing the (lack of) introduction of certain participatory features in both markets; b) offering the first longitudinal perspective in that field for both markets; and, c) analyzing the various influences of market size on participatory journalism implementation. The longitudinal overview confirms that changes are happening at a fast pace. In general, the availability of participatory features on national Flemish and German newspaper Web sites is comparable, as both markets belong largely to the same journalistic culture. The larger part of the dissimilarities is explained by the difference in market size.

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