Volume 29 Issue 2, February 2022

Genetic and genome-wide analysis of a catalytically deficient SETDB1-like enzyme, MET-2, in Caenorhabditis elegans reveals that MET-2 promotes transcriptional silencing and fertility through both H3K9 methylation and focus formation, which blocks histone acetylation.

Courtney et al. found that the C-terminal amphipathic helix of a presynaptic protein, complexin, can dramatically remodel phospholipid bilayers. This activity enables complexin to increase the size and stability of SNARE-mediated fusion pores.

NHA2 exchanges sodium ions for protons across cell membranes, and its activity is linked to the pathogenesis of diabetes mellitus and essential hypertension in humans. Drew et al. report the cryo-EM structure of NHA2 in detergent and nanodiscs.

The authors solve the cryo-EM structure of nucleotide-free Chd1 bound to a nucleosome to dissect how Chd1 shifts DNA onto the histone core, and also report that recognition of the acidic patch by Chd1 blocks action of competing chromatin remodelers.

Here, the authors provide mechanistic evidence for the piRNA pathway connection to the heterochromatin machinery in Drosophila.

Activation of the Tn7 transposase depends on the Tn7-encoded AAA+ ATPase adaptor, TnsC. A new cryo-EM structure reveals how TnsC targets DNA sequences between target and insertion sites to restrict insertion events to control sequence-specific transposon insertion.

The authors solve structures of the bacterial ribosome bound to the peptidyl transferase center targeting antibiotic chloramphenicol with adjacent growing peptide chains to explain the context-specificity of action of this antibiotic.

The authors determine the cryo-EM structures of prokaryotic ribosomes with the oxazolidinone antibiotics linezolid and radezolid bound to the peptidyl transferase center with an adjacent growing nascent peptide chain, providing an explanation for their context-specific action.

Cryo-EM structures of the porcine respiratory complex I reveal how Q10 is bound and reduced in the Q chamber comprising four different Q10-binding sites. A ‘two-Q’ model is proposed for the coupling mechanism of complex I.