The bulk of eukaryotic diversity is microbial, with macroscopic lineages such as plant, animals and fungi nesting among a plethora of diverse lineages that include amoebae, flagellates, ciliates, and many types of algae. Our understanding of the evolutionary relationships and genome properties of microbial eukaryotes is rapidly advancing through analyses of omics (transcriptomic, genomic) data. However, phylogenomic analyses are challenging for microeukaryotes, and particularly uncultivable lineages, as single-cell approaches generate a mixture of sequence data from hosts, associated microbiomes, and contaminants.
View Article and Find Full Text PDFMemories are encoded by sparse populations of neurons but how such sparsity arises remains largely unknown. We found that a neuron's eligibility to be recruited into the memory trace depends on its epigenetic state prior to encoding. Principal neurons in the mouse lateral amygdala display intrinsic chromatin plasticity, which when experimentally elevated favors neuronal allocation into the encoding ensemble.
View Article and Find Full Text PDFOptic neuropathies are characterized by the degeneration of the optic nerves and represent a considerable individual and societal burden. Notably, Leber's hereditary optic neuropathy (LHON) is a devastating vision disease caused by mitochondrial gene mutations that hinder oxidative phosphorylation and increase oxidative stress, leading to the loss of retinal ganglion neurons and axons. Loss of vision is rapid and severe, predominantly in young adults.
View Article and Find Full Text PDFThe ribotoxic stress response (RSR) is a signaling pathway in which the p38- and c-Jun N-terminal kinase (JNK)-activating mitogen-activated protein kinase kinase kinase (MAP3K) ZAKα senses stalling and/or collision of ribosomes. Here, we show that reactive oxygen species (ROS)-generating agents trigger ribosomal impairment and ZAKα activation. Conversely, zebrafish larvae deficient for ZAKα are protected from ROS-induced pathology.
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