RESUMEN
During entry, non-enveloped viruses penetrate a host membrane to cause infection, although how this is accomplished remains enigmatic. Polyomaviruses (PyVs) are non-enveloped DNA viruses that penetrate the endoplasmic reticulum (ER) membrane to reach the cytosol en route to the nucleus for infection. To penetrate the ER membrane, the prototype PyV simian virus 40 (SV40) induces formation of ER-escape sites, called foci, composed of repeating units of multi-tubular ER junctions where the virus is thought to exit. How SV40 triggers formation of the ER-foci harboring these multi-tubular ER junctions is unclear. Here, we show that the ER morphogenic atlastin 2 (ATL2) and ATL3 membrane proteins play critical roles in SV40 infection. Mechanistically, ATL3 mobilizes to the ER-foci where it deploys its GTPase-dependent membrane fusion activity to promote formation of multi-tubular ER junctions within the ER-foci. ATL3 also engages an SV40-containing membrane penetration complex. By contrast, ATL2 does not reorganize to the ER-foci. Instead, it supports the reticular ER morphology critical for the integrity of the ATL3-dependent membrane complex. Our findings illuminate how two host factors play distinct roles in the formation of an essential membrane penetration site for a non-enveloped virus. IMPORTANCE Membrane penetration by non-enveloped viruses, a critical infection step, remains enigmatic. The non-enveloped PyV simian virus 40 (SV40) penetrates the endoplasmic reticulum (ER) membrane to reach the cytosol en route for infection. During ER-to-cytosol membrane penetration, SV40 triggers formation of ER-associated structures (called ER-foci) that function as the membrane penetration sites. Here, we discover a role of the ATL ER membrane proteins-known to shape the ER morphology-during SV40-induced ER-foci formation. These findings illuminate how a non-enveloped virus hijacks host components to construct a membrane penetration structure.
Asunto(s)
Membranas Intracelulares , Chaperonas Moleculares , Membranas Intracelulares/metabolismo , Chaperonas Moleculares/metabolismo , Internalización del Virus , Retículo Endoplásmico/metabolismo , Proteínas de la Membrana/metabolismoRESUMEN
OBJECTIVE: Many children in low-income and middle-income countries are disadvantaged in achieving early developmental potential in childhood as they lack the necessary support from their surroundings, including from parents and caregivers. Digital technologies, such as smartphone apps, coupled with iterative codesign to engage end-users in the technology-delivered content development stages, can help overcome gaps in early child development (ECD). We describe the iterative codesign and quality improvement process that informs the development of content for the Thrive by Five International Program, localised for nine countries in Asia and Africa. DESIGN: Between 2021 and 2022, an average of six codesign workshops in each country were conducted in Afghanistan, Indonesia, Kyrgyzstan, Uzbekistan, Cameroon, the Democratic Republic of the Congo, Ethiopia, Kenya and Namibia.ParticipantsA total of 174 parents and caregivers and 58 in-country subject matter experts participated and provided feedback to refine and inform the cultural appropriateness of the Thrive by Five app and its content. Detailed notes from the workshops and written feedback were coded and analysed using established thematic techniques. RESULTS: Four themes emerged from the codesign workshops: local realities, barriers to positive parenting, child development and lessons learnt about the cultural context. These themes, as well as various subthemes, informed content development and refinement. For example, childrearing activities were requested and developed to promote inclusion of families from diverse backgrounds, encourage best parenting practices, increase engagement of fathers in ECD, address parents' mental well-being, educate children about cultural values and help bereaved children with grief and loss. Also, content that did not align with the laws or culture of any country were removed. CONCLUSIONS: The iterative codesign process informed the development of a culturally relevant app for parents and caregivers of children in the early years. Further evaluation is required to assess user experience and impact in real world settings.
Asunto(s)
Aplicaciones Móviles , Responsabilidad Parental , Niño , Humanos , Preescolar , Responsabilidad Parental/psicología , Países en Desarrollo , Cognición , CamerúnRESUMEN
BACKGROUND: Digital technologies are widely recognized for their equalizing effect, improving access to affordable health care regardless of gender, ethnicity, socioeconomic status, or geographic region. The Thrive by Five app is designed to promote positive interactions between children and their parents, extended family, and trusted members of the community to support socioemotional and cognitive development in the first 5 years of life and to strengthen connections to culture and community. OBJECTIVE: This paper aims to describe the iterative co-design process that underpins the development and refinement of Thrive by Five's features, functions, and content. Minderoo Foundation commissioned this work as a quality improvement activity to support an engaging user experience and inform the development of culturally appropriate and relevant content for parents and caregivers in each country where the app is implemented. METHODS: The app content, referred to as Collective Actions, comprises "The Why," that presents scientific principles that underpin socioemotional and cognitive development in early childhood. The scientific information is coupled with childrearing activities for parents, extended family, and members of the community to engage in with the children to support their healthy development and to promote positive connections between parents, families, and communities and these young children. Importantly, the initial content is designed and iteratively refined in collaboration with a subject matter expert group from each country (ie, alpha testing). This content is then configured into the app (either a beta version or localized version) for testing (ie, beta testing) by local parents and caregivers as well as experts who are invited to provide their feedback and suggestions for improvements in app content, features, and functions via a brief web-based survey and a series of co-design workshops. The quantitative survey data will be analyzed using descriptive statistics, whereas the analysis of qualitative data from the workshops will follow established thematic techniques. RESULTS: To date, the co-design protocol has been completed with subject matter experts, parents, and caregivers from 9 countries, with the first results expected to be published by early 2023. The protocol will be implemented serially in the remaining 21 countries. CONCLUSIONS: Mobile technologies are the primary means of internet connection in many countries worldwide, which underscores the potential for mobile health programs to improve access to valuable, evidence-based, and previously unavailable parenting information. However, for maximum impact, it is critically important to ensure that mobile health programs are designed in collaboration with the target audience to support the alignment of content with parents' cultural values and traditions and its relevance to their needs and circumstances. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/39225.
RESUMEN
Nuclear entry represents the final and decisive infection step for most DNA viruses, although how this is accomplished by some viruses is unclear. Polyomavirus SV40 transports from the cell surface through the endosome, the endoplasmic reticulum, and the cytosol from where it enters the nucleus to cause infection. Here we elucidate the nuclear entry mechanism of SV40. Our results show that cytosol-localized SV40 is targeted to the nuclear envelope by directly engaging Nesprin-2 of the linker of nucleoskeleton and cytoskeleton (LINC) nuclear membrane complex. Additionally, we identify the NUP188 subunit of the nuclear pore complex (NPC) as a new Nesprin-2-interacting partner. This physical proximity positions the NPC to capture SV40 upon release from Nesprin-2, enabling the channel to facilitate nuclear translocation of the virus. Strikingly, SV40 disassembles during nuclear entry, generating a viral genome-VP1-VP3 subcomplex that efficiently crosses the NPC to enter the nucleus. Our results reveal how two major nuclear membrane protein complexes are exploited to promote targeting and translocation of a virus into the nucleus.
Asunto(s)
Poro Nuclear , Virus , Núcleo Celular/metabolismo , Citoesqueleto/metabolismo , Membrana Nuclear/metabolismo , Matriz NuclearRESUMEN
OBJECTIVE: Transillumination and laparoscopic visualization are two techniques recommended to minimize the risks of injury to abdominal wall structures during insertion of secondary trocars. This study was designed to determine the effectiveness of these techniques to locate the epigastric vessels and superior bladder margin. DESIGN: Prospective observational. SETTING: Academic medical centers. PATIENT(S): One hundred five women undergoing laparoscopy for tubal sterilization, infertility, pelvic masses, or pelvic pain. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): The ability to visualize the superficial and inferior epigastric vessels, and bladder margin; body mass index (BMI; in kilograms per meter squared); and skin color. RESULT(S): Transillumination successfully visualized 64% of superficial epigastric vessels and was less effective both as weight increased (BMI <25 kg/m(2): 86%; BMI = 25-30 kg/m(2): 61%; BMI >30 kg/m(2): 25%) and in dark-skinned women (69%) compared to those with lighter skin (42%). Laparoscopic visualization successfully identified 82% of inferior epigastric vessels and 46% of bladder margins, and was less effective as weight increased. CONCLUSION(S): Transillumination can successfully locate superficial epigastric vessels, and laparoscopic visualization can locate inferior epigastric vessels and the superior bladder margin in the majority of women undergoing laparoscopy. Transillumination is less effective in dark-skinned women, and both techniques are less effective with increasing body weight.