A5044188303- Genetics, Aging, and Longevity in Model Organisms
- Reproductive Biology and Fertility
- Circadian rhythm and melatonin
- Evolution and Genetic Dynamics
- CRISPR and Genetic Engineering
- Spaceflight effects on biology
- Radiation Dose and Imaging
- Mitochondrial Function and Pathology
- Pluripotent Stem Cells Research
- Cellular transport and secretion
- Pharmacogenetics and Drug Metabolism
- Marine Ecology and Invasive Species
- Adolescent and Pediatric Healthcare
- Neurogenesis and neuroplasticity mechanisms
- Nematode management and characterization studies
- Nanoparticles: synthesis and applications
- Neonatal Health and Biochemistry
- Health, Environment, Cognitive Aging
- Marine Invertebrate Physiology and Ecology
- Nerve injury and regeneration
- Alcohol Consumption and Health Effects
- Chromosomal and Genetic Variations
- Cellular Mechanics and Interactions
- Bioenergy crop production and management
- Wnt/β-catenin signaling in development and cancer
University of North Carolina at Chapel Hill
2020-2025
University of North Carolina Health Care
2024
T.K.M. College of Arts and Science
2023
Duke University
2017-2019
University of Chicago
2010-2015
Dartmouth Hospital
2010
Dartmouth College
2010
Izaak Walton Killam Health Centre
2006
University of California, San Francisco
2001
Children's Medical Research Institute
1996
The actin-based microfilament system is thought to play a critical role in neuronal development. We have determined specific changes the composition of microfilaments accompanying morphogenesis. By using antibodies against isoforms for tropomyosin (Tm) (Tm-5 and TmBr-1/-3) actin (beta- gamma-actin), we found that during early morphogenesis vivo immature growing axons contain beta- gamma-actin Tm-5. In particular, Tm-5 exclusively located axonal processes relative cell body. contrast,...
Abstract Exercise and caloric restriction improve health, including reducing risk of cardiovascular disease, neurological cancer. However, molecular mechanisms underlying these protections are poorly understood, partly due to the cost time investment mammalian long-term diet exercise intervention studies. We subjected Caenorhabditis elegans nematodes a 6-day, twice daily swimming regimen, during which animals also experienced brief, transient food deprivation. Accordingly, we included...
Stem cells reside in and rely upon their niche to maintain stemness but must balance self-renewal with the production of daughters that leave differentiate. We discovered a mechanism stem cell exit canonical C. elegans distal tip (DTC) germ mediated by previously unobserved, thin, membranous protrusions adjacent somatic gonad pair (Sh1). A disproportionate number divisions were observed at DTC-Sh1 interface. Stem-like differentiating fates segregated across this boundary. Spindles polarized,...
Phenotypes that appear to be conserved could maintained not only by strong purifying selection on the underlying genetic systems, but also stabilizing acting via compensatory mutations with balanced effects. Such coevolution has been invoked explain experimental results, rarely focus of study. Conserved expression driven unc-47 promoters Caenorhabditis elegans and C. briggsae persists despite divergence within a cis-regulatory element between this trans-regulatory environment. Compensatory...
Using a recently published scRNA-seq dataset of adult C. elegans hermaphrodites, we identified previously unknown regulator the germ line stem cell niche (the distal tip cell, or DTC). The gene mig-21 has highest "marker score"-yet no known role-in DTC. classical genetics techniques, RNAi knockdown, and live imaging, discovered that integrates information from Wnt Netrin pathways to guide anteroposterior dorsoventral DTC migration. Our study demonstrates utility datasets in revealing...
Abstract Membrane trafficking is a crucial function of all cells and regulated at multiple levels from vesicle formation, packaging, localization to fusion, exocytosis, endocytosis. Rab GTPase proteins are core regulators eukaryotic membrane trafficking, but developmental roles specific GTPases less well characterized, potentially because their essentiality for basic cellular function. C. elegans gonad development entails the coordination cell growth, proliferation, migration—processes in...
Different functional constraints contribute to different evolutionary rates across genomes. To understand why some sequences evolve faster than others in a single cis-regulatory locus, we investigated function and dynamics of the promoter Caenorhabditis elegans unc-47 gene. We found that this consists two distinct domains. The proximal is conserved largely sufficient direct appropriate spatial expression. distal displays little if any conservation between several closely related nematodes....
The transcription factor COE (collier/olfactory-1/early B cell factor) is an unusual basic helix-loop-helix as it lacks a domain and maintained single copy gene in the genomes of all currently analysed non-vertebrate Metazoan genomes. Given unique features gene, its proposed ancestral role specification chemosensory neurons wealth functional data from vertebrates Drosophila, evolutionary history can be readily investigated. We have examined ways which expression has diversified among Metazoa...
Gene regulatory information guides development and shapes the course of evolution. To test conservation gene regulation within phylum Nematoda, we compared functions putative cis-regulatory sequences four sets orthologs (unc-47, unc-25, mec-3 elt-2) from distantly-related nematode species. These species, Caenorhabditis elegans, its congeneric C. briggsae, three parasitic species Meloidogyne hapla, Brugia malayi, Trichinella spiralis, represent five major clades in Nematoda. Despite great...
The Caenorhabditis elegans adult hermaphrodite germline is surrounded by a thin tube formed somatic sheath cells that support germ as they mature from the stem-like mitotic state through meiosis, gametogenesis, and ovulation. Recently, we discovered distal Sh1 associate with exit niche Gordon et al., 2020. Here, report these sheath-associated differentiate first in animals temperature-sensitive mutations affecting cell state, are maintained to boundary. We analyze several markers of sheath,...
Abstract Polyploid cells contain more than two copies of each chromosome. Polyploidy has important roles in development, evolution, and tissue regeneration/repair, can arise as a programmed polyploidization event or be triggered by stress. Cancer are often polyploid. C. elegans nematodes typically diploid, but stressors such heat shock starvation trigger the production tetraploid offspring. In this study, we utilized recently published protocol to generate stable strains compared their...
Membrane trafficking is a crucial function of all cells and regulated at multiple levels from vesicle formation, packaging, localization to fusion, exocytosis, endocytosis. Rab GTPase proteins are core regulators eukaryotic membrane trafficking, but developmental roles specific GTPases less well characterized, potentially because their essentiality for basic cellular function.
Polyploid cells contain more than two copies of each chromosome. Polyploidy has important roles in development, evolution, and tissue regeneration/repair, can arise as a programmed polyploidization event or be triggered by stress. Cancer are often polyploid. C. elegans nematodes typically diploid, but stressors such heat shock starvation trigger the production tetraploid offspring. In this study, we utilized recently published protocol to generate stable strains compared their physiological...
Data on nuclear medicine thyroid examinations performed in Manitoba (population 1 million) from 1981-1985 were collected, with more detailed demographic data obtained 1,100 consecutive patients between June 1987 and January 1988. An average of 2,081 examined per year, 81% female 19% male, representing 8.4% all procedures. Typical administered activity associated HE patient 238.0 MBq 1.5 mSv for 99mTc, 7.4 1.2 123I, 0.33 3.9 131I. Based NCRP risk estimates explicit corrections age, sex,...