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Biology subjects

Pieters, J.

Publications and source records attributed to Pieters, J..

2 recordsLinked to original sources

Implementation of Ribo-BiFC method to plant systems using a split mVenus approach

Translation is a fundamental process for every living organism. In plants, the rate of translation is tightly modulated during development and in response to environmental cues. However, it is difficult to measure the actual translation state of the tissues in vivo. Here, we report the implementation of an in vivo translation marker based on bimolecular fluorescence complementation, the Ribo-BiFC. We combined method originally developed for fruit-fly with an improved low background split-mVenus BiFC system previously described in plants. We labelled Arabidopsis thaliana small subunit ribosomal protein (RPS) and large subunit ribosomal protein (RPL) with fragments of the mVenus fluorescent protein. Upon the assembly of the 80S ribosome, the mVenus fragments complemented and were detected by fluorescent microscopy. We show that these recombinant proteins are in close proximity in the tobacco epidermal cells, although the signal is reduced when compared to BiFC signal from known interactors. This Ribo-BiFC method system can be used in stable transgenic lines to enable visualisation of translational rate in plant tissues and could be used to study translation dynamics and its changes during plant development, under abiotic stress or in different genetic backgrounds.

plant biology↗

A novel approach to single cell analysis to reveal intrinsic differences in immune marker expression in unstimulated macrophages from BALB/c and C57BL/6 mouse strains

Macrophages are cells of the innate immune system that provide the first line of defense against pathogens. Their functional and morphological heterogeneity is well known, though the origin of this heterogeneity is still debated. Furthermore, while mouse strains differ in the type of immune responses that they mount to individual pathogens, the range of gene expression variation among their macrophages in the absence of a specific stimulus is not known. By applying single cell RNA sequencing we here reveal the gene expression variation in pre-stimulation macrophage populations from specific pathogen-free BALB/c and C57BL/6 mice, two mouse strains that give prototypical Th2 and Th1-biased immune responses, directed towards extracellular or intracellular pathogens, respectively. We show that intrinsic differences between the macrophages of these two strains are detectable before any specific stimulation and we place the gene expression profile of these cells within the range of variation that is measured upon in vitro stimulation with pro-inflammatory lipopolysaccharide (LPS) and interferon {gamma} (IFN), or anti-inflammatory IL-4. We find that C57BL/6 mice show stronger evidence of macrophage polarization than BALB/c mice, which could explain their resistance to pathogens such as Leishmania. Our computational methods for analyzing single cell RNA sequencing data, controlling for common sources of stochastic variation, can be more generally adopted to uncover biological variation between cell populations.

systems biology↗