Highlights d Chromatin undergoes liquid-liquid phase separation (LLPS) under physiologic conditions d Linker DNA length and patterning, histone H1, and acetylation modulate chromatin LLPS d Acetylated chromatin only phase separates upon binding multi-bromodomain proteins d LLPS could enable establishment and maintenance of distinct chromatin compartments

Macroautophagic clearance of cytosolic materials entails the initiation, growth, and closure of autophagosomes. Cargo triggers the assembly of a web of cargo receptors and core machinery. ATG9 vesicles seed the growing autophagosomal membrane, which is supplied by de novo phospholipid synthesis, phospholipid transport via ATG2 proteins, and lipid flipping by ATG9. Autophagosomes close via the ESCRT complexes. Here we review recent discoveries that illuminate the molecular mechanisms of autophagosome formation and discuss emerging questions in this rapidly developing field.

The selective autophagy pathways of xenophagy and mitophagy are initiated when the adaptor NDP52 recruits the ULK1 complex to autophagic cargo. Hydrogen-deuterium exchange coupled to mass spectrometry (HDX-MS) was used to map the membrane and NDP52 binding sites of the ULK1 complex to unique regions of the coiled coil of the FIP200 subunit. Electron microscopy of the full-length ULK1 complex shows that the FIP200 coiled coil projects away from the crescent-shaped FIP200 N-terminal domain dimer. NDP52 allosterically stimulates membrane-binding by FIP200 and the ULK1 complex by promoting a more dynamic conformation of the membrane-binding portion of the FIP200 coiled coil. Giant unilamellar vesicle (GUV) reconstitution confirmed that membrane recruitment by the ULK1 complex is triggered by NDP52 engagement. These data reveal how the allosteric linkage between NDP52 and the ULK1 complex could drive the first membrane recruitment event of phagophore biogenesis in xenophagy and mitophagy.