Human papillomaviruses (HPVs) are the causative agent of warts. Infections with high-risk HPVs are associated with anogenital and head and neck cancers. One of the viral genes responsible for HPV's oncogenic activity is E6. Mice expressing the HPV-16 E6 protein in their epidermis (K14E6 WT ) develop epithelial hyperplasia and squamous carcinomas. Numerous cellular proteins interact with E6, some of which can be grouped based on common amino acid motifs in their E6-binding domains. One such group, the PDZ partners, including hDLG, hSCRIBBLE, MUPP1, and MAGI, bind to the carboxy-terminal four amino acids of E6 through their PDZ domains. E6's interaction with the PDZ partners leads to their degradation. Additionally, E6's binding to PDZ proteins has been correlated with its ability to transform baby rat kidney cells in tissue culture and to confer tumorigenicity onto cells in xenograft experiments. To address whether the ability of E6 to bind PDZ domain partners is necessary for E6 to confer epithelial hyperproliferation in vivo, we generated transgenic mice that express in stratified squamous epithelia a mutant of E6 lacking the last six amino acids at its carboxyl terminus, E6 ⌬146-151 , from the human keratin 14 (K14) promoter. The K14E6 ⌬146-151 mice exhibit a radiation response similar to that of the K14E6 WT mice, demonstrating that this protein, as predicted, retains an ability to inactivate p53. However, the K14E6 ⌬146-151 mice fail to display epithelial hyperplasia. These results indicate that an interaction of E6 with PDZ partners is necessary for its induction of epithelial hyperplasia.Human papillomaviruses (HPVs) are the causative agent of warts. Infections with high-risk HPVs are associated with anogenital (27) and head and neck cancers (18,25). HPVs encode two oncogenes, E6 and E7, which are thought to contribute to cervical cancers because they are selectively induced in their expression in those cancers. E6 and E7 are multifunctional proteins best known for their abilities to bind and inactivate the p53 and pRb cellular tumor suppressors, respectively. E6 binds in a ternary complex with p53 and a cellular ubiquitin ligase, E6AP (10). This complex results in ubiquitination and degradation of p53 through the proteosome pathway (11). Thus, E6 abrogates p53 function. However, E6's oncogenic activities cannot be explained entirely by its effects on p53. E6's ability to transform cells does not always correlate with its ability to degrade p53; mutants of E6 that cannot induce p53 degradation are still able to immortalize mammary epithelial cells (13, 19), transform 3Y1 rat fibroblasts, and confer tumorigenicity onto 2 mouse fibroblast cells (14). Conversely, some E6 mutations that retain the ability to induce p53 degradation are unable to transform cells (5, 13). Studies with K14E6 WT mice also have identified p53-independent activities. Mice expressing the HPV type 16 (HPV-16) E6 protein in their epidermis (K14E6 WT ) develop epithelial hyperplasia (31). However, this phenotype has not been observed in...

Background Researchers have long recognized that stigma is a global, multi-level phenomenon requiring intervention approaches that target multiple levels including individual, interpersonal, community, and structural levels. While existing interventions have produced modest reductions in stigma, their full reach and impact remain limited by a nearly exclusive focus targeting only one level of analysis. Methods We conducted the first systematic review of original research on multi-level stigma-reduction interventions. We used the following eligibility criteria for inclusion: (1) peer-reviewed, (2) contained original research, (3) published prior to initiation of search on November 30, 2017, (4) evaluated interventions that operated on more than one level, and (5) examined stigma as an outcome. We stratified and analyzed articles by several domains, including whether the research was conducted in a low-, middle-, or high-income country. Results Twenty-four articles met the inclusion criteria. The articles included a range of countries (low, middle, and high income), stigmatized conditions/populations (e.g., HIV, mental health, leprosy), intervention targets (e.g., people living with a stigmatized condition, health care workers, family, and community members), and stigma reduction strategies (e.g., contact, social marketing, counseling, faith, problem solving), with most using education-based approaches. A total of 12 (50%) articles examined community-level interventions alongside interpersonal and/or intrapersonal levels, but only 1 (4%) combined a structural-level intervention with another level. Of the 24 studies, only 6 (25%) were randomized controlled trials. While most studies (17 of 24) reported statistically significant declines in at least one measure of stigma, fewer than half reported measures of practical significance (i.e., effect size); those that were reported varied widely in magnitude and were typically in the small-to-moderate range. Conclusions While there has been progress over the past decade in the development and evaluation of multi-level stigma interventions, much work remains to strengthen and expand this approach. We highlight several opportunities for new research and program development.

SUMMARY Regulation of neuronal excitability and cardiac excitation-contraction coupling requires proper localization of L-type Ca2+ channels. We show that the actin-binding protein α-actinin binds to the C-terminal surface targeting motif of α11.2, the central pore-forming CaV1.2 subunit, to foster its surface expression. Disruption of α-actinin function by dominant negative or shRNA constructs reduces CaV1.2 surface localization in HEK293 and neuronal cultures, and dendritic spine localization in neurons. We demonstrate that calmodulin displaces α-actinin from their shared binding site on α11.2 upon Ca2+ influx through L-type channels but not through NMDAR, thereby triggering loss of CaV1.2 from spines. Coexpression of a Ca2+-binding deficient calmodulin mutant does not affect basal CaV1.2 surface expression, but inhibits its internalization upon Ca2+ influx. We conclude that α-actinin stabilizes CaV1.2 at the plasma membrane, and that its displacement by Ca2+-calmodulin induces Ca2+-induced endocytosis of CaV1.2, thus providing an important negative feedback mechanism for Ca2+ influx.

The widespread noradrenergic innervation in the brain promotes arousal and learning by molecular mechanisms that remain largely undefined. Recent work shows that the β(2)-adrenergic receptor (β(2)AR) is linked to the AMPA-type glutamate receptor subunit GluA1 via stargazin and PSD-95 (Joiner ML, Lise MF, Yuen EY, Kam AY, Zhang M, Hall DD, Malik ZA, Qian H, Chen Y, Ulrich JD, Burette AC, Weinberg RJ, Law PY, El-Husseini A, Yan Z, Hell JW. EMBO J 29: 482-495, 2010). We now demonstrate that the β(2)AR plays a prominent role in long-term potentiation (LTP) induced by a train of 900 stimuli at 5 Hz (prolonged theta-tetanus-LTP, or PTT-LTP) in the hippocampal CA1 region in mice, which requires simultaneous β-adrenergic stimulation. Although PTT-LTP was impaired in hippocampal slices from β(1)AR and β(2)AR knockout (KO) mice, only β(2)AR-selective stimulation with salbutamol supported this PTT-LTP in wild-type (WT) slices, whereas β(1)AR-selective stimulation with dobutamine (+ prazosin) did not. Furthermore, only the β(2)AR-selective antagonist ICI-118551 and not the β(1)AR-selective antagonist CGP-20712 inhibited PTT-LTP and phosphorylation of GluA1 on its PKA site S845 in WT slices. Our analysis of S845A knockin (KI) mice indicates that this phosphorylation is relevant for PTT-LTP. These results identify the β(2)AR-S845 signaling pathway as a prominent regulator of synaptic plasticity.

The roles of PDZ domain-containing proteins such as Dlg and Scrib have been well described for Drosophila; however, their requirement for mammalian development is poorly understood. Here we show that Dlg, Scrib, MAGI1, MAGI3, and MPDZ are expressed in the mouse ocular lens. We demonstrate that the increase in proliferation and defects in cellular adhesion and differentiation observed in epithelia of lenses that express E6, a viral oncoprotein that can bind to several PDZ proteins, including the human homologs of Dlg and Scrib, is dependent on E6's ability to bind these proteins via their PDZ domains. Analyses of lenses from mice carrying an insertional mutation in Dlg (dlg gt ) show increased proliferation and proliferation in spatially inappropriate regions of the lens, a phenotype similar to that of lenses expressing E6. The results from this study indicate that multiple PDZ domain-containing proteins, including Dlg and Scrib, may be required for maintaining the normal pattern of growth and differentiation in the lens. Furthermore, the phenotypic similarities among the Drosophila dlg mutant, the lenses of dlg gt mice, and the lenses of E6 transgenic mice suggest that Dlg may have a conserved function in regulating epithelial cell growth and differentiation across species.Determining the molecular mechanisms that regulate cell growth and differentiation during the critical phase of organogenesis in vivo has been a central theme in developmental biology for many years. Inherent in this process is a fundamental switch of a cell from a state capable of proliferation to one that is irreversibly withdrawn from the cell cycle and undergoing terminal differentiation. Disruption of cell cycle control often has adverse consequences, such as defects in development, tumorigenesis, and cell death. The retinoblastoma susceptibility protein, pRb, is a critical regulator of cell proliferation during development (26,31). Evidence from studies in invertebrates suggests that perhaps other proteins with tumor suppressor properties, such as the PDZ (PSD-95/Dlg/ZO-1) domain-containing proteins, which include Discs Large (Dlg) and Scribble (Scrib), are also important in regulating mammalian cell growth and differentiation (3, 42). To address the possible role of PDZ domain-containing proteins in regulating growth and differentiation of epithelial tissues in vertebrates, we have examined the consequences of the functional disruption of some of these PDZ proteins on cell growth and differentiation in the mouse ocular lens.The mouse ocular lens is an ideal system in which to identify the cellular factors that are required for maintaining proper cell cycle control. In the postnatal mouse, the lens can be divided into two major compartments, the anterior epithelium and the fiber cell compartment. The anterior epithelium is a monolayer of cuboidal epithelial cells that covers the anterior surface. Within the epithelium reside specific groups of cells at spatially restricted positions that exhibit different proliferative characteristics. I...