Small GTPase
- Rap1 and membrane lipids cooperatively recruit talin to trigger integrin activation
Summary: Talin requires cooperative Rap1 binding to its F0 and F1 domains and lipid binding to the F2 domain for its recruitment to adhesion sites to trigger integrin activation.
- The Joubert syndrome protein ARL13B binds tubulin to maintain uniform distribution of proteins along the ciliary membrane
Summary: The Joubert syndrome protein ARL13B binds tubulin to maintain uniform distribution of proteins along the ciliary membrane.
- Arl8b is required for lysosomal degradation of maternal proteins in the visceral yolk sac endoderm of mouse embryos
Summary: The small GTPase Arl8b, known to be involved in lysosomal function, contributes to mouse embryonic growth by mediating lysosomal degradation of maternal proteins in the visceral yolk sac endoderm.
- The F-actin-binding RapGEF GflB is required for efficient macropinocytosis in Dictyostelium
Summary: Dictyostelium GflB, known as a Rap1 GEF, interacts with F-actin via its N-terminal villin headpiece (VHP)-like domain and regulates macropinocytic and phagocytic cup formation and retraction.
- Microscopy analysis of reconstituted COPII coat polymerization and Sec16 dynamics
Highlighted Article: COPII components mediate the formation of transport carriers from the ER. Fluorescence microscopy analysis of artificial planar membrane is used to define the dynamics of COPII coat polymerization.
- Rab2a and Rab27a cooperatively regulate the transition from granule maturation to exocytosis through the dual effector Noc2
Summary: Although regulated exocytosis comprises several sequential steps, the mechanisms coordinating each step are poorly understood. These findings suggest that Noc2 regulates the transition between Rab2a- and Rab27a-mediated exocytosis.
- PI3K regulates endocytosis after insulin secretion by mediating signaling crosstalk between Arf6 and Rab27a
Summary: The insulin secretagogue glucose activates PI3K and induces endocytosis through promoting signaling crosstalk between Arf6 and Rab27a pathways.
- Mon1–Ccz1 activates Rab7 only on late endosomes and dissociates from the lysosome in mammalian cells
Highlighted Article: A combination of a Rab7 sensor and confocal FRET imaging techniques revealed that the Mon1–Ccz1 complex activates Rab7 only on late endosome and dissociates from lysosome in mammalian cells.