ABSTRACT
The Tre1 G-protein coupled receptor (GPCR) was discovered to be required for Drosophila germ cell (GC) coalescence almost two decades ago, yet the molecular events both upstream and downstream of Tre1 activation remain poorly understood. To gain insight into these events, we describe a bona fide null allele and both untagged and tagged versions of Tre1. We find that the primary defect with complete Tre1 loss is the failure of GCs to properly navigate, with GC mis-migration occurring from early stages. We find that Tre1 localizes with F-actin at the migration front, along with PI(4,5)P2; dPIP5K, an enzyme that generates PI(4,5)P2; and dWIP, a protein that binds activated Wiskott-Aldrich syndrome protein (WASP), which stimulates F-actin polymerization. We show that Tre1 is required for polarized accumulation of F-actin, PI(4,5)P2, and dPIP5K. Smoothened also localizes with F-actin at the migration front, and Hh, through Smo, increases levels of Tre1 at the plasma membrane and Tre1's association with dPIP5K.
Subject(s)
Actin Cytoskeleton/metabolism , Drosophila Proteins/metabolism , Drosophila melanogaster/metabolism , Embryonic Germ Cells/metabolism , Hedgehog Proteins/metabolism , Phosphatidylinositol 4,5-Diphosphate/metabolism , Receptors, G-Protein-Coupled/metabolism , Actin Cytoskeleton/genetics , Animals , Animals, Genetically Modified , Cell Movement , Drosophila Proteins/genetics , Drosophila melanogaster/embryology , Drosophila melanogaster/genetics , Hedgehog Proteins/genetics , Receptors, Cell Surface/genetics , Receptors, Cell Surface/metabolism , Receptors, G-Protein-Coupled/genetics , Signal Transduction , Smoothened Receptor/genetics , Smoothened Receptor/metabolism , Time Factors , Wiskott-Aldrich Syndrome Protein/genetics , Wiskott-Aldrich Syndrome Protein/metabolismABSTRACT
Purpose: Low-income children with high caries risk are disproportionately affected by poor access to dental care. Retail-based clinics (RBCs) can provide accessible ancillary oral health care. The purposes of this study were: (1) to measure caregivers' acceptance rate of an oral health screening, fluoride varnish (FV) application, and caries risk assessment offered to children on a walk-in basis in an RBC; and (2) to categorize the caries risk and demographics among the participants.
Methods: Screenings and FV applications were provided to children younger than 18 years at a Walgreens Health Care Clinic in Baltimore, Md., USA, from October 2016 to October 2017. The acceptance rate and caries risk using the American Dental Association caries risk assessment form were documented. Descriptive statistics and Fisher's exact test were used to analyze the data.
Results: Eighty-five children and their caretakers were approached and 32 (38 percent) agreed to participate. Most children had high caries risk (84.3 percent) and a dental home (81.2 percent), but only 50 percent reported visiting their dentist in the last year.
Conclusion: Our results demonstrate modest acceptance of FV application for children on a convenience basis. This population had predominantly high caries risk, with poor adherence to follow-up with their dental home. Retail-based dental care should not replace the dental home but could support it by increasing access to preventive dental care in children. (J Dent Child 2019;86(1):40-6)
Received July 2, 2018; Last Revision August 13, 2018; Accepted August 13, 2018.
