University of California, Davis

About: University of California, Davis is a education organization based out in Davis, California, United States. It is known for research contribution in the topics: Population & Gene. The organization has 78770 authors who have published 180033 publications receiving 8064158 citations. The organization is also known as: UC Davis & UCD.

Gut inflammation provides a respiratory electron acceptor for Salmonella

Abstract: Salmonella enterica serotype Typhimurium (S. Typhimurium) causes acute gut inflammation by using its virulence factors to invade the intestinal epithelium and survive in mucosal macrophages. The inflammatory response enhances the transmission success of S. Typhimurium by promoting its outgrowth in the gut lumen through unknown mechanisms. Here we show that reactive oxygen species generated during inflammation react with endogenous, luminal sulphur compounds (thiosulphate) to form a new respiratory electron acceptor, tetrathionate. The genes conferring the ability to use tetrathionate as an electron acceptor produce a growth advantage for S. Typhimurium over the competing microbiota in the lumen of the inflamed gut. We conclude that S. Typhimurium virulence factors induce host-driven production of a new electron acceptor that allows the pathogen to use respiration to compete with fermenting gut microbes. Thus the ability to trigger intestinal inflammation is crucial for the biology of this diarrhoeal pathogen.

Conserved cell types with divergent features in human versus mouse cortex.

Abstract: Elucidating the cellular architecture of the human cerebral cortex is central to understanding our cognitive abilities and susceptibility to disease. Here we used single-nucleus RNA-sequencing analysis to perform a comprehensive study of cell types in the middle temporal gyrus of human cortex. We identified a highly diverse set of excitatory and inhibitory neuron types that are mostly sparse, with excitatory types being less layer-restricted than expected. Comparison to similar mouse cortex single-cell RNA-sequencing datasets revealed a surprisingly well-conserved cellular architecture that enables matching of homologous types and predictions of properties of human cell types. Despite this general conservation, we also found extensive differences between homologous human and mouse cell types, including marked alterations in proportions, laminar distributions, gene expression and morphology. These species-specific features emphasize the importance of directly studying human brain.

Techniques in insect nematology

Abstract: Publisher Summary This chapter focuses on the techniques used for identifying, isolating, propagating, assaying, and preserving nematodes that are parasitic in or pathogenic to insects. Nematodes are nonsegmented animals with excretory, nervous, digestive, reproductive, and muscular systems but lacking circulatory and respiratory systems. The stage of entomogenous and entomopathogenic nematodes that is infective varies depending on the group. A good stereomicroscope is essential for nematode identification and should have a range of magnification between 10 and 100X, a fairly fiat field, and good resolution. The gonads and other structures of fixed nematodes may be obscured by the granular appearance of the intestine. Specimens can be cleared by processing to lactophenol or glycerin. The cephalic structures and the number of longitudinal chords are diagnostic characters for genetic or specific determination of certain groups of nematodes. Extraction methods for insect nematodes are derived from techniques developed with plant-parasitic nematodes. It is found that the most common methods are the Baermann funnel, sieving, elutriation, and centrifugal flotation.

The Collaborative Cross, a community resource for the genetic analysis of complex traits

Abstract: The goal of the Complex Trait Consortium is to promote the development of resources that can be used to understand, treat and ultimately prevent pervasive human diseases. Existing and proposed mouse resources that are optimized to study the actions of isolated genetic loci on a fixed background are less effective for studying intact polygenic networks and interactions among genes, environments, pathogens and other factors. The Collaborative Cross will provide a common reference panel specifically designed for the integrative analysis of complex systems and will change the way we approach human health and disease.