Tag Archives: wu min

Frequency and amplitude control of cortical oscillations by phosphoinositide waves

by Ding Xiong, Shengping Xiao, Su Guo, Qinsong Lin, Fubito Nakatsu & Min Wu

Nature Chemical Biology (2016) doi:10.1038/nchembio.2000
Published online 11 January 2016

Rhythmicity is prevalent in the cortical dynamics of diverse single and multicellular systems. Current models of cortical oscillations focus primarily on cytoskeleton-based feedbacks, but information on signals upstream of the actin cytoskeleton is limited. In addition, inhibitory mechanisms—especially local inhibitory mechanisms, which ensure proper spatial and kinetic controls of activation—are not well understood. Here, we identified two phosphoinositide phosphatases, synaptojanin 2 and SHIP1, that function in periodic traveling waves of rat basophilic leukemia (RBL) mast cells. The local, phase-shifted activation of lipid phosphatases generates sequential waves of phosphoinositides. By acutely perturbing phosphoinositide composition using optogenetic methods, we showed that pulses of PtdIns(4,5)P2 regulate the amplitude of cyclic membrane waves while PtdIns(3,4)P2 sets the frequency. Collectively, these data suggest that the spatiotemporal dynamics of lipid metabolism have a key role in governing cortical oscillations and reveal how phosphatidylinositol 3-kinases (PI3K) activity could be frequency-encoded by a phosphatase-dependent inhibitory reaction.

Read online: Nature Chemical Biology.

Learn more about Wu Min‘s research.

Calcium oscillations-coupled conversion of actin travelling waves to standing oscillations

by Wu M, Wu X, De Camilli P

Proc Natl Acad Sci USA  2013 Jan 22;110(4):1339-44

Dynamic spatial patterns of signaling factors or macromolecular assemblies in the form of oscillations or traveling waves have emerged as important themes in cell physiology. Feedback mechanisms underlying these processes and their modulation by signaling events and reciprocal cross-talks remain poorly understood. In this work we show that antigen stimulation of mast cells triggers cyclic recruitment of curvature-generating protein FBP17 and actin regulatory factors that can be manifested in either spatial pattern. Further mechanistic studies revealed an unexpected pattern-rendering mechanism.

Read online: PNAS.

Learn more about Wu Min’s research.