0000000000348852
AUTHOR
Stefan Günther
Single-cell profiling reveals GPCR heterogeneity and functional patterning during neuroinflammation.
GPCR expression was intensively studied in bulk cDNA of leukocyte populations, but limited data are available with respect to expression in individual cells. Here, we show a microfluidic-based single-cell GPCR expression analysis in primary T cells, myeloid cells, and endothelial cells under naive conditions and during experimental autoimmune encephalomyelitis, the mouse model of multiple sclerosis. We found that neuroinflammation induces characteristic changes in GPCR heterogeneity and patterning, and we identify various functionally relevant subgroups with specific GPCR profiles among spinal cord-infiltrating CD4 T cells, macrophages, microglia, or endothelial cells. Using GPCRs CXCR4, S1…
Proteomics of Galápagos Marine Iguanas Links Function of Femoral Gland Proteins to the Immune System
Femoral glands secrete a wax-like substance on the inner side of lizard hind legs, which is thought to function as a mode of chemical communication. Though the minor volatile fraction is well studied, the major protein fraction remains enigmatic. Here, we use proteomics to analyze proteins in femoral gland secretions of the Galápagos marine iguana. Although we found no evidence for proteins and peptides involved in chemical communication, we found several immune-regulatory proteins which also demonstrate anti-microbial functions. Accordingly, we show that femoral gland proteins and peptides function as a barrier against microbial infection and may prevent the rapid degradation of volatile s…
Skeletal muscle-specific methyltransferase METTL21C trimethylates p97 and regulates autophagy-associated protein breakdown
Summary: Protein aggregates and cytoplasmic vacuolization are major hallmarks of multisystem proteinopathies (MSPs) that lead to muscle weakness. Here, we identify METTL21C as a skeletal muscle-specific lysine methyltransferase. Insertion of a β-galactosidase cassette into the Mettl21c mouse locus revealed that METTL21C is specifically expressed in MYH7-positive skeletal muscle fibers. Ablation of the Mettl21c gene reduced endurance capacity and led to age-dependent accumulation of autophagic vacuoles in skeletal muscle. Denervation-induced muscle atrophy highlighted further impairments of autophagy-related proteins, including LC3, p62, and cathepsins, in Mettl21c−/− muscles. In addition, w…