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Andreas Müller, Martin Neukam, Anna Ivanova, Anke Sönmez, Carla Münster, Susanne Kretschmar, Yannis Kalaidzidis, Thomas Kurth, Jean-Marc Verbavatz, Michele Solimena
A Global Approach for Quantitative Super Resolution and Electron Microscopy on Cryo and Epoxy Sections Using Self-labeling Protein Tags.
Sci Rep, 7 Art. No. 23 (2017)
  PubMed   

Correlative light and electron microscopy (CLEM) is a powerful approach to investigate the molecular ultrastructure of labeled cell compartments. However, quantitative CLEM studies are rare, mainly due to small sample sizes and the sensitivity of fluorescent proteins to strong fixatives and contrasting reagents for EM. Here, we show that fusion of a self-labeling protein to insulin allows for the quantification of age-distinct insulin granule pools in pancreatic beta cells by a combination of super resolution and transmission electron microscopy on Tokuyasu cryosections. In contrast to fluorescent proteins like GFP organic dyes covalently bound to self-labeling proteins retain their fluorescence also in epoxy resin following high pressure freezing and freeze substitution, or remarkably even after strong chemical fixation. This enables for the assessment of age-defined granule morphology and degradation. Finally, we demonstrate that this CLEM protocol is highly versatile, being suitable for single and dual fluorescent labeling and detection of different proteins with optimal ultrastructure preservation and contrast.
@article{Müller6796,
author={Andreas Müller, Martin Neukam, Anna Ivanova, Anke Sönmez, Carla Münster, Susanne Kretschmar, Yannis Kalaidzidis, Thomas Kurth, Jean-Marc Verbavatz, Michele Solimena},
title={A Global Approach for Quantitative Super Resolution and Electron Microscopy on Cryo and Epoxy Sections Using Self-labeling Protein Tags.},
journal={Scientific reports},
volume={7},
pages={null--null},
year=2017
}

Mesut Bilgin, Andrej Shevchenko
Quantification of endogenous endocannabinoids by LC-MS/MS
In: Lipidomics. (Eds.) Paul Wood (Neuromethods ; 125).,New York,Springer (2017),99-107 Ch. 7
  

Here, we describe the LC-MS/MS quantification of 46 molecules representing five major classes of endogenous endocannabinoids and endocannabinoid-related compounds in human blood serum and its lipoprotein fractions.

Jussi Helppi, Ronald Naumann, Marianne Asikainen, Jaakko Mononen, Oliver Zierau
Novel Bedding Material Results in Poor Pregnancy Rate with CD-1 Female Mice Used as Fosters for Producing Transgenic Mice
Scand. J. Lab. Anim. Sci., 43(3) 1-5 (2017)
  

The impact of a novel bedding material (cotton cloth) on the reproductive performance (pregnancy rate and production of offspring) was studied in foster females used for producing transgenic mice. Embryos injected with DNA were transferred to pseudo-pregnant foster females housed under standard conditions (aspen bedding and nesting material). After embryo transfer, mice were divided between the experimental group (AGREBE cotton cloth) and control group (aspen bedding and nesting material). Pregnant mice were observed at day 15 after the transfer and the number of offspring was recorded on post-natal days 3 and 21. Altogether 116 foster mice were used as embryo recipients. Significantly more pregnancies were observed in the control group versus the experimental group: 43% and 19% of foster mice, respectively. Informal interviews with animal caretakers revealed a general dislike towards the cotton cloth (dirtier cages, mice often found on the plastic cage surface, difficult husbandry routines). The cotton cloth showed major signs of wear and tear after only a few weeks of usage. In conclusion, this study with female mice demonstrated that a cotton cloth cannot be recommended as a sole replacement for bedding and nesting material.
@article{Helppi6850,
author={Jussi Helppi, Ronald Naumann, Marianne Asikainen, Jaakko Mononen, Oliver Zierau},
title={Novel Bedding Material Results in Poor Pregnancy Rate with CD-1 Female Mice Used as Fosters for Producing Transgenic Mice },
journal={Scandinavian Journal of Labooratory Animal Science},
volume={43},
issue ={3},
pages={1--5},
year=2017
}

Malou Zuidscherwoude, Vera-Marie E Dunlock, Geert van den Bogaart, Sjoerd J van Deventer, Alie van der Schaaf, Jenny van Oostrum, Joachim Goedhart, Joanna In 't Hout, Günter J Hämmerling, Satoshi Tanaka, André Nadler, Carsten Schultz, Mark D Wright, Merel J W Adjobo-Hermans, Annemiek B van Spriel
Tetraspanin microdomains control localized protein kinase C signaling in B cells.
Sci Signal, 10(478) Art. No. eaag2755 (2017)
PubMed   

Activation of B cells by the binding of antigens to the B cell receptor (BCR) requires the protein kinase C (PKC) family member PKCβ. Because PKCs must translocate to the plasma membrane to become activated, we investigated the mechanisms regulating their spatial distribution in mouse and human B cells. Through live-cell imaging, we showed that BCR-stimulated production of the second messenger diacylglycerol (DAG) resulted in the translocation of PKCβ from the cytosol to plasma membrane regions containing the tetraspanin protein CD53. CD53 was specifically enriched at sites of BCR signaling, suggesting that BCR-dependent PKC signaling was initiated at these tetraspanin microdomains. Fluorescence lifetime imaging microscopy studies confirmed the molecular recruitment of PKC to CD53-containing microdomains, which required the amino terminus of CD53. Furthermore, we showed that Cd53-deficient B cells were defective in the phosphorylation of PKC substrates. Consistent with this finding, PKC recruitment to the plasma membrane was impaired in both mouse and human CD53-deficient B cells compared to that in their wild-type counterparts. These data suggest that CD53 promotes BCR-dependent PKC signaling by recruiting PKC to the plasma membrane so that it can phosphorylate its substrates and that tetraspanin-containing microdomains can act as signaling hotspots in the plasma membrane.
@article{Zuidscherwoude6843,
author={Malou Zuidscherwoude, Vera-Marie E Dunlock, Geert van den Bogaart, Sjoerd J van Deventer, Alie van der Schaaf, Jenny van Oostrum, Joachim Goedhart, Joanna In 't Hout, Günter J Hämmerling, Satoshi Tanaka, André Nadler, Carsten Schultz, Mark D Wright, Merel J W Adjobo-Hermans, Annemiek B van Spriel},
title={Tetraspanin microdomains control localized protein kinase C signaling in B cells.},
journal={Science signaling},
volume={10},
issue ={478},
pages={null--null},
year=2017
}

J Gray Camp, Barbara Treutlein
Human development: Advances in mini-brain technology.
Nature, 545(7652) 39-40 (2017)
PubMed  

@article{Camp6855,
author={J Gray Camp, Barbara Treutlein},
title={Human development: Advances in mini-brain technology.},
journal={Nature},
volume={545},
issue ={7652},
pages={39--40},
year=2017
}

Carlos Ocaña-Morgner, Susanne Sales, Manuela Rothe, Andrej Shevchenko, Rolf Jessberger
Tolerogenic versus Immunogenic Lipidomic Profiles of CD11c(+) Immune Cells and Control of Immunogenic Dendritic Cell Ceramide Dynamics.
J Immunol, Art. No. doi: 10.4049/jimmunol.1601928 (2017)
PubMed   

Lipids affect the membrane properties determining essential biological processes. Earlier studies have suggested a role of switch-activated protein 70 (SWAP-70) in lipid raft formation of dendritic cells. We used lipidomics combined with genetic and biochemical assays to analyze the role of SWAP-70 in lipid dynamics. TLR activation using LPS as a ligand represented a pathogenic immunogenic stimulus, physical disruption of cell-cell contacts a tolerogenic stimulus. Physical disruption, but not LPS, caused an increase of phosphatidylcholine ether and cholesteryl esters in CD11c(+) immune cells. An increase of ceramide (Cer) was a hallmark for LPS activation. SWAP-70 was required for regulating the increase and localization of Cers in the cell membrane. SWAP-70 controls Cer accumulation through the regulation of pH-dependent acid-sphingomyelinase activity and of RhoA-dependent transport of endosomal contents to the plasma membrane. Poor accumulation of Cers in Swap70(-/-) cells caused decreased apoptosis. This shows that two different pathways of activation, immunogenic and tolerogenic, induce different changes in the lipid composition of cultured CD11c(+) cells, and highlights the important role of SWAP-70 in Cer dynamics in dendritic cells.
@article{Ocaña-Morgner6845,
author={Carlos Ocaña-Morgner, Susanne Sales, Manuela Rothe, Andrej Shevchenko, Rolf Jessberger},
title={Tolerogenic versus Immunogenic Lipidomic Profiles of CD11c(+) Immune Cells and Control of Immunogenic Dendritic Cell Ceramide Dynamics.},
journal={Journal of immunology (Baltimore, Md. : 1950)},
volume={},
pages={1--1},
year=2017
}

Salman F Banani, Hyun-Ok Kate Lee, Anthony Hyman, Michael K Rosen
Biomolecular condensates: organizers of cellular biochemistry.
Nat Rev Mol Cell Biol, 18(5) 285-298 (2017)
PubMed   

Biomolecular condensates are micron-scale compartments in eukaryotic cells that lack surrounding membranes but function to concentrate proteins and nucleic acids. These condensates are involved in diverse processes, including RNA metabolism, ribosome biogenesis, the DNA damage response and signal transduction. Recent studies have shown that liquid-liquid phase separation driven by multivalent macromolecular interactions is an important organizing principle for biomolecular condensates. With this physical framework, it is now possible to explain how the assembly, composition, physical properties and biochemical and cellular functions of these important structures are regulated.
@article{Banani6797,
author={Salman F Banani, Hyun-Ok Kate Lee, Anthony Hyman, Michael K Rosen},
title={Biomolecular condensates: organizers of cellular biochemistry.},
journal={Nature reviews. Molecular cell biology},
volume={18},
issue ={5},
pages={285--298},
year=2017
}

Shradha Das, Elisabeth Knust
Stardust, the Janus-faced partner of Crumbs.
J Cell Biol, 216(5) 1219-1221 (2017)
PubMed   

The Drosophila melanogaster scaffolding protein Stardust (Sdt) stabilizes the transmembrane protein Crumbs, a conserved regulator of apical-basal epithelial polarity. In this issue, Perez-Mockus et al. (2017. J. Cell Biol https://doi.org/10.1083/jcb.201611196) report that a subset of Sdt isoforms are targeted by the ubiquitin ligase Neuralized, thus fine tuning the endocytosis and activity of this apical determinant.
@article{Das6839,
author={Shradha Das, Elisabeth Knust},
title={Stardust, the Janus-faced partner of Crumbs.},
journal={The Journal of cell biology},
volume={216},
issue ={5},
pages={1219--1221},
year=2017
}

Caren Norden
Pseudostratified epithelia - cell biology, diversity and roles in organ formation at a glance.
J Cell Sci, Art. No. doi: 10.1242/jcs.192997 (2017)
PubMed   

Pseudostratified epithelia (PSE) are widespread and diverse tissue arrangements, and many PSE are organ precursors in a variety of organisms. While cells in PSE, like other epithelial cells, feature apico-basal polarity, they generally are more elongated and their nuclei are more densely packed within the tissue. In addition, nuclei in PSE undergo interkinetic nuclear migration (IKNM, also referred to as INM), whereby all mitotic events occur at the apical surface of the elongated epithelium. Previous reviews have focused on the links between IKNM and the cell cycle, as well as the relationship between IKNM and neurogenesis, which will not be elaborated on here. Instead, in this Cell Science at a Glance article and the accompanying poster, I will discuss the cell biology of PSEs, highlighting how differences in PSE architecture could influence cellular behaviour, especially IKNM. Furthermore, I will summarize what we know about the links between apical mitosis in PSE and tissue integrity and maturation.
@article{Norden6846,
author={Caren Norden},
title={Pseudostratified epithelia - cell biology, diversity and roles in organ formation at a glance.},
journal={Journal of cell science},
volume={},
pages={1--1},
year=2017
}

Irena Kuzmanovska, Andreas Milias-Argeitis, Jan Mikelson, Christoph Zechner, Mustafa Khammash
Parameter inference for stochastic single-cell dynamics from lineage tree data.
BMC Syst Biol, 11(1) Art. No. 52 (2017)
PubMed   

With the advance of experimental techniques such as time-lapse fluorescence microscopy, the availability of single-cell trajectory data has vastly increased, and so has the demand for computational methods suitable for parameter inference with this type of data. Most of currently available methods treat single-cell trajectories independently, ignoring the mother-daughter relationships and the information provided by the population structure. However, this information is essential if a process of interest happens at cell division, or if it evolves slowly compared to the duration of the cell cycle.
@article{Kuzmanovska6856,
author={Irena Kuzmanovska, Andreas Milias-Argeitis, Jan Mikelson, Christoph Zechner, Mustafa Khammash},
title={Parameter inference for stochastic single-cell dynamics from lineage tree data.},
journal={BMC systems biology},
volume={11},
issue ={1},
pages={null--null},
year=2017
}