bioRxiv Science⌕ Search

Biology subjects

Peyrard, S.

Publications and source records attributed to Peyrard, S..

2 recordsLinked to original sources

Astrocyte glucocorticoid signaling mediates cognitive impairment induced by early-life stress

Early-life stress can have lifelong consequences, enhancing stress susceptibility and resulting in behavioural and cognitive deficits. While the effects of early-life stress on neuronal function have been well-described, we still know very little about the contribution of non-neuronal brain cells. Investigating the complex interactions between distinct brain cell types is critical to fully understand how cellular changes manifest as behavioural deficits following early-life stress. Here, using male and female mice we report that early-life stress induces anxiety-like behaviour and fear generalisation in an amygdala-dependent learning and memory task. These behavioural changes were associated with impaired synaptic plasticity, increased neural excitability, and astrocyte hypofunction. Genetic perturbation of amygdala astrocyte function by either reducing astrocyte calcium activity or reducing astrocyte network function was sufficient to replicate cellular, synaptic, and fear memory generalisation associated with early-life stress. Our data reveal a role of astrocytes in tuning emotionally salient memory and provide mechanistic links between early-life stress, astrocyte hypofunction, and behavioural deficits. Summary Figure O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=157 SRC="FIGDIR/small/519598v4_ufig1.gif" ALT="Figure 1"> View larger version (33K): org.highwire.dtl.DTLVardef@1d9a228org.highwire.dtl.DTLVardef@124ff67org.highwire.dtl.DTLVardef@1fbe186org.highwire.dtl.DTLVardef@19362fb_HPS_FORMAT_FIGEXP M_FIG C_FIG

neuroscience↗

The soybean rust pathogen Phakopsora pachyrhizi displays transposable element proliferation that correlates with broad host-range adaptation on legumes

Asian soybean rust, caused by Phakopsora pachyrhizi, is one of the worlds most economically damaging agricultural diseases. Despite P. pachyrhizis impact, the exceptional size and complexity of its genome prevented generation of an accurate genome assembly. We simultaneously sequenced three P. pachyrhizi genomes uncovering a genome up to 1.25 Gb comprising two haplotypes with a transposable element (TE) content of ~93%. The proliferation of TEs within the genome occurred in several bursts and correlates with the radiation and speciation of the legumes. We present data of clear de-repression of TEs that mirrors expression of virulence-related candidate effectors. We can see a unique expansion in amino acid metabolism for this fungus. Our data shows that TEs play a dominant role in P. pachyrhizis genome and have a key impact on various processes such as host range adaptation, stress responses and genetic plasticity of the genome.

microbiology↗