Pollard discovered the first unconventional myosin (myosin-I) and provided the first direct link between cytoplasmic actin filaments and cellular movements. He characterized the mechanism of actin polymerization and discovered and characterized two key proteins that regulate actin assembly, capping protein and Arp2/3 complex. His work on regulation of actin polymerization led to the highly influential dendritic nucleation hypothesis for how assembly of branched actin filaments produce forces for cellular movements. Pollard also discovered that myosin-II concentrates in the cytokinetic cleavage furrow, a key observation supporting the concept that a contractive ring of actin filaments and myosin pinches cells in two. His investigation of the molecular pathway of cytokinesis in fission yeast culminated in molecularly explicit mathematical models that accurately account for the assembly and constriction of the contractile ring and provide the physical basis for understanding how cells regulate the system during the transitions in the cell cycle.

Research Interests

Pollard's laboratory is currently investigating high-resolution structures of actin filaments and their interactions with partner proteins, the mechanism of actin filament nucleation and the molecular composition of the cytokinetic contractile ring.

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Primary Section

Section 29: Biophysics and Computational Biology

Secondary Section

Section 22: Cellular and Developmental Biology