98%
921
2 minutes
20
Epithelial tissues are composed of polarized cells with distinct apical and basolateral membrane domains. In the Drosophila ovarian follicle cell epithelium, apical membranes are specified by Crumbs (Crb), Stardust (Sdt), and the aPKC-Par6-cdc42 complex. Basolateral membranes are specified by Lethal giant larvae (Lgl), Discs large (Dlg), and Scribble (Scrib). Apical and basolateral determinants are known to act in a mutually antagonistic fashion, but it remains unclear how this interaction generates polarity. We have built a computer model of apicobasal polarity that suggests that the combination of positive feedback among apical determinants plus mutual antagonism between apical and basal determinants is essential for polarization. In agreement with this model, in vivo experiments define a positive feedback loop in which Crb self-recruits via Crb-Crb extracellular domain interactions, recruitment of Sdt-aPKC-Par6-cdc42, aPKC phosphorylation of Crb, and recruitment of Expanded (Ex) and Kibra (Kib) to prevent endocytic removal of Crb from the plasma membrane. Lgl antagonizes the operation of this feedback loop, explaining why apical determinants do not normally spread into the basolateral domain. Once Crb is removed from the plasma membrane, it undergoes recycling via Rab11 endosomes. Our results provide a dynamic model for understanding how epithelial polarity is maintained in Drosophila follicle cells.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.cub.2012.04.020 | DOI Listing |
JMIR Res Protoc
September 2025
School of Rehabilitation Science, University of Saskatchewan, Saskatoon, SK, Canada.
Background: In Canada, the Indigenous population is the youngest and fastest growing, yet ongoing health disparities for Indigenous peoples are widely recognized. There is a concerning lack of research on childhood disabilities and health conditions in Indigenous populations in Canada. For children with disabilities and chronic health conditions, ongoing access to rehabilitation services, such as occupational therapy, physical therapy, speech-language pathology, and audiology, is critical in promoting positive health and developmental outcomes.
View Article and Find Full Text PDFJMIR Res Protoc
September 2025
Institute for Collaboration on Health, Intervention, and Policy, University of Connecticut, Storrs, CT, United States.
Background: Children in the United States have poor diet quality, increasing their risk for chronic disease burden later in life. Caregivers' feeding behaviors are a critical factor in shaping lifelong dietary habits. The Strong Families Start at Home/Familias Fuertes Comienzan en Casa (SFSH) was a 6-month, home-based, pilot randomized-controlled feasibility trial that aimed to improve the diet quality of 2-5-year-old children and promote positive parental feeding practices among a predominantly Hispanic/Latine sample.
View Article and Find Full Text PDFJMIR Serious Games
September 2025
Global Health Institute, American University of Beirut, PO Box 11-0236, Riad El Solh, Beirut, 1107 2020, Lebanon, 961 3047578.
Background: High maternal morbidity and mortality rates globally, especially in low-income and lower-middle-income countries, highlight the critical role of skilled health care providers (HCPs) in preventing pregnancy-related complications among disadvantaged populations. Lebanon, hosting over 1.5 million refugees, is no exception.
View Article and Find Full Text PDFMol Cell Biochem
September 2025
Peking University Third Hospital, Beijing, China.
Cardiovascular-Kidney-Metabolic (CKM) syndrome, a newly defined systemic disorder, is characterized by the pathological interplay among diabetes, chronic kidney disease (CKD), and cardiovascular disease (CVD). Recent studies have identified chronic inflammation not only as a central mediator in the pathological progression of CKM syndrome but also as a pivotal molecular hub that drives coordinated damage across multiple organ systems. Mechanistic investigations have revealed that aberrant activation of signaling pathways such as NF-κB, Wnt, PI3K-AKT, JAK-STAT, and PPAR constitutes a complex inflammatory regulatory network.
View Article and Find Full Text PDFACS Synth Biol
September 2025
School of Biological and Health Systems Engineering, Arizona State University, Tempe, Arizona 85281, United States.
Cellular resource limitations create unintended interactions among synthetic gene circuit modules, compromising circuit modularity. This challenge is particularly pronounced in circuits with positive feedback, where uneven resource allocation can lead to Winner-Takes-All (WTA) behavior, favoring one module at the expense of others. In this study, we experimentally implemented a Negatively Competitive Regulatory (NCR) controller using CRISPR interference (CRISPRi) and evaluated its effectiveness in mitigating WTA behavior in two gene circuits: dual self-activation and cascading bistable switch.
View Article and Find Full Text PDF