TY  - JOUR
A1  - Berger, Nathalie
A1  - Demolombe, Vincent
A1  - Hem, Sonia
A1  - Rofidal, Valérie
A1  - Steinmann, Laura
A1  - Krouk, Gabriel
A1  - Crabos, Amandine
A1  - Nacry, Philippe
A1  - Verdoucq, Lionel
A1  - Santoni, Véronique
T1  - Root membrane ubiquitinome under short-term osmotic stress
JF  - International Journal of Molecular Sciences
N2  - Osmotic stress can be detrimental to plants, whose survival relies heavily on proteomic plasticity. Protein ubiquitination is a central post-translational modification in osmotic-mediated stress. In this study, we used the K-Ɛ-GG antibody enrichment method integrated with high-resolution mass spectrometry to compile a list of 719 ubiquitinated lysine (K-Ub) residues from 450 Arabidopsis root membrane proteins (58% of which are transmembrane proteins), thereby adding to the database of ubiquitinated substrates in plants. Although no ubiquitin (Ub) motifs could be identified, the presence of acidic residues close to K-Ub was revealed. Our ubiquitinome analysis pointed to a broad role of ubiquitination in the internalization and sorting of cargo proteins. Moreover, the simultaneous proteome and ubiquitinome quantification showed that ubiquitination is mostly not involved in membrane protein degradation in response to short osmotic treatment but that it is putatively involved in protein internalization, as described for the aquaporin PIP2;1. Our in silico analysis of ubiquitinated proteins shows that two E2 Ub-conjugating enzymes, UBC32 and UBC34, putatively target membrane proteins under osmotic stress. Finally, we revealed a positive role for UBC32 and UBC34 in primary root growth under osmotic stress.
KW  - aquaporin
KW  - mass spectrometry
KW  - osmotic stress
KW  - ubiquitination
Y1  - 2022
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-284003
SN  - 1422-0067
VL  - 23
IS  - 4
ER  - 
TY  - JOUR
A1  - Schwerk, Christian
A1  - Papandreou, Thalia
A1  - Schuhmann, Daniel
A1  - Nickol, Laura
A1  - Borkowski, Julia
A1  - Steinmann, Ulrike
A1  - Quednau, Natascha
A1  - Stump, Carolin
A1  - Weiss, Christel
A1  - Berger, Jürgen
A1  - Wolburg, Hartwig
A1  - Claus, Heike
A1  - Vogel, Ulrich
A1  - Ishikawa, Hiroshi
A1  - Tenenbaum, Tobias
A1  - Schroten, Horst
T1  - Polar Invasion and Translocation of Neisseria meningitidis and Streptococcus suis in a Novel Human Model of the Blood-Cerebrospinal Fluid Barrier
JF  - PLoS One
N2  - Acute bacterial meningitis is a life-threatening disease in humans. Discussed as entry sites for pathogens into the brain are the blood-brain and the blood-cerebrospinal fluid barrier (BCSFB). Although human brain microvascular endothelial cells (HBMEC) constitute a well established human in vitro model for the blood-brain barrier, until now no reliable human system presenting the BCSFB has been developed. Here, we describe for the first time a functional human BCSFB model based on human choroid plexus papilloma cells (HIBCPP), which display typical hallmarks of a BCSFB as the expression of junctional proteins and formation of tight junctions, a high electrical resistance and minimal levels of macromolecular flux when grown on transwell filters. Importantly, when challenged with the zoonotic pathogen Streptococcus suis or the human pathogenic bacterium Neisseria meningitidis the HIBCPP show polar bacterial invasion only from the physiologically relevant basolateral side. Meningococcal invasion is attenuated by the presence of a capsule and translocated N. meningitidis form microcolonies on the apical side of HIBCPP opposite of sites of entry. As a functionally relevant human model of the BCSFB the HIBCPP offer a wide range of options for analysis of disease-related mechanisms at the choroid plexus epithelium, especially involving human pathogens.
KW  - gene expression
KW  - plexus epithelial-cells
KW  - central-nervous-system
KW  - microvascular endothelial-cells
KW  - choroid-plexus
KW  - in vitro
KW  - brain barrier
KW  - tight junctions
KW  - meningococcal disease
KW  - bacterial meningitis
Y1  - 2012
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-131459
VL  - 7
IS  - 1
ER  -