Snap Chip for Cross-reactivity-free and Spotter-free Multiplexed Sandwich Immunoassays.

Multiplexed protein analysis has shown superior diagnostic sensitivity and accuracy compared to single proteins. Antibody microarrays allow for thousands of micro-scale immunoassays performed simultaneously on a single chip. Sandwich assay format improves assay specificity by detecting each target with two antibodies, but suffers from cross-reactivity between reagents thus limiting their multiplexing capabilities.

Calnuc Function in Endosomal Sorting of Lysosomal Receptors.

Calnuc is a ubiquitous Ca(2+)-binding protein present on the trans-Golgi network (TGN) and endosomes. However, the precise role of Calnuc in these organelles is poorly characterized. We previously highlighted the role of Calnuc in the transport of LRP9, a new member of a low-density lipoprotein (LDL) receptor subfamily that cycles between the TGN and endosomes.

Macrocyclic cell penetrating peptides: a study of structure-penetration properties.

Arginine-rich cell penetrating peptides are short cationic peptides able to cross biological membranes despite their peptidic character. In order to optimize their penetration properties and further elucidate their mechanisms of cellular entry, these peptides have been intensively studied for the last two decades. Although several parameters are simultaneously involved in the internalization mechanism, recent studies suggest that structural modifications influence cellular internalization.

Topology and membrane anchoring of the lysosomal storage disease-related protein CLN5.

One late infantile variant of the neurodegenerative disease neuronal ceroid lipofuscinosis (NCL) is caused by a mutation in the CLN5 gene. CLN5 encodes a lysosomal glycoprotein whose structure and function have not yet been clearly defined. In the present study, we used epitope-tagged CLN5 to determine the topology and solubility of the CLN5 protein.

Calnuc binds to LRP9 and affects its endosomal sorting.

Calnuc is an ubiquitous Ca(++)-binding protein found in the cytoplasm where it binds different Galpha subunits, in the Golgi lumen where it constitutes a major Ca(++) storage pool, and outside the cell. We identified LDLR-related protein 9 (LRP9) as the first transmembrane protein shown to interact directly with Calnuc. LRP9 is a member of a new subfamily of the LDLR superfamily that cycles between the trans-Golgi network (TGN) and endosomes through a mechanism dependent on clathrin adaptor GGA proteins.

Intracellular trafficking of LRP9 is dependent on two acidic cluster/dileucine motifs.

LDL receptor-related protein 9 (LRP9) is a distant member of the low-density lipoprotein receptor (LDLR) superfamily. To date, there are no reports on the cellular distribution of LRP9 or the signals responsible for its localization. Here, we investigated the intracellular localization and trafficking of LRP9.