C-terminal amides mark proteins for degradation via SCF-FBXO31.

During normal cellular homeostasis, unfolded and mislocalized proteins are recognized and removed, preventing the build-up of toxic byproducts. When protein homeostasis is perturbed during ageing, neurodegeneration or cellular stress, proteins can accumulate several forms of chemical damage through reactive metabolites. Such modifications have been proposed to trigger the selective removal of chemically marked proteins; however, identifying modifications that are sufficient to induce protein degradation has remained challenging.

Deciphering regulation of FOXP3 expression in human conventional T cells.

FOXP3 is a lineage-defining transcription factor that controls differentiation and maintenance of suppressive function of regulatory T cells (Tregs). Foxp3 is exclusively expressed in Tregs in mice. However, in humans, FOXP3 is not only constitutively expressed in Tregs; it is also transiently expressed in stimulated CD4+CD25- conventional T cells (Tconvs).

Intercellular nanotube-mediated mitochondrial transfer enhances T cell metabolic fitness and antitumor efficacy.

Mitochondrial loss and dysfunction drive T cell exhaustion, representing major barriers to successful T cell-based immunotherapies. Here, we describe an innovative platform to supply exogenous mitochondria to T cells, overcoming these limitations. We found that bone marrow stromal cells establish nanotubular connections with T cells and leverage these intercellular highways to transplant stromal cell mitochondria into CD8 T cells.

Removal of TREX1 activity enhances CRISPR-Cas9-mediated homologous recombination.

CRISPR-Cas9-mediated homology-directed repair (HDR) can introduce desired mutations at targeted genomic sites, but achieving high efficiencies is a major hurdle in many cell types, including cells deficient in DNA repair activity. In this study, we used genome-wide screening in Fanconi anemia patient lymphoblastic cell lines to uncover suppressors of CRISPR-Cas9-mediated HDR. We found that a single exonuclease, TREX1, reduces HDR efficiency when the repair template is a single-stranded or linearized double-stranded DNA.