Ronald S. Rock

Associate Professor
Research Summary
Cells use an extensive toolkit of myosin motor proteins to traffic materials, anchor components, and control their shape. The focus of our group is to understand biological motion, specifically how motor proteins navigate the cytoskeleton and dynamically organize cells. We use a multifaceted approach, constructing advanced single-molecule fluorescence microscopes and optical tweezers to watch how myosins move in vitro and in whole cells. We also use structural biology tools to understand how myosin architecture and quaternary structure regulates motility.
Keywords
Single Molecule, Myosins, Actin Cytoskeleton, Optical Tweezers, TIRF Microscopy, Structural Biology
Education
  • Stanford University, Palo Alto, CA, Postdoc, Spudich Lab Biochemistry 2004
  • Caltech, Pasadena, CA, Ph.D. Chemistry 1998
  • University of Chicago, Chicago, IL, B.S. Chemistry 1992
Biosciences Graduate Program Association
Awards & Honors
  • 1999 - Helen Hay Whitney Postdoctoral Fellow
  • 2002 - Burroughs Wellcome Career Award at the Scientific Interface
Publications
  1. LILAC: enhanced actin imaging with an optogenetic Lifeact. Nat Methods. 2023 02; 20(2):214-217. View in: PubMed

  2. 4-Hydroxyacetophenone modulates the actomyosin cytoskeleton to reduce metastasis. Proc Natl Acad Sci U S A. 2020 09 08; 117(36):22423-22429. View in: PubMed

  3. How Actin Tracks Affect Myosin Motors. Adv Exp Med Biol. 2020; 1239:183-197. View in: PubMed

  4. Snapshots of a molecular swivel in action. Nucleic Acids Res. 2018 06 01; 46(10):5286-5296. View in: PubMed

  5. Tail-Anchored Protein Insertion by a Single Get1/2 Heterodimer. Cell Rep. 2017 Sep 05; 20(10):2287-2293. View in: PubMed

  6. Investigations of human myosin VI targeting using optogenetically controlled cargo loading. Proc Natl Acad Sci U S A. 2017 02 28; 114(9):E1607-E1616. View in: PubMed

  7. Myosin light chain kinase steady-state kinetics: comparison of smooth muscle myosin II and nonmuscle myosin IIB as substrates. Cell Biochem Funct. 2016 Oct; 34(7):469-474. View in: PubMed

  8. Competition between Coiled-Coil Structures and the Impact on Myosin-10 Bundle Selection. Biophys J. 2016 06 07; 110(11):2517-2527. View in: PubMed

  9. Actin age orchestrates myosin-5 and myosin-6 run lengths. Curr Biol. 2015 Aug 03; 25(15):2057-62. View in: PubMed

  10. Pharmacological activation of myosin II paralogs to correct cell mechanics defects. Proc Natl Acad Sci U S A. 2015 Feb 03; 112(5):1428-33. View in: PubMed

  11. The development and application of a quantitative peptide microarray based approach to protein interaction domain specificity space. Mol Cell Proteomics. 2014 Dec; 13(12):3647-62. View in: PubMed

  12. Molecular motors: a finicky myosin V chooses its own path. Curr Biol. 2012 Aug 07; 22(15):R606-8. View in: PubMed

  13. The optical trapping dumbbell assay for nonprocessive motors or motors that turn around filaments. Cold Spring Harb Protoc. 2011 Nov 01; 2011(11):1372-4. View in: PubMed

  14. Attachment of anti-GFP antibodies to microspheres for optical trapping experiments. Cold Spring Harb Protoc. 2011 Nov 01; 2011(11):1370-1. View in: PubMed

  15. Optical traps to study properties of molecular motors. Cold Spring Harb Protoc. 2011 Nov 01; 2011(11):1305-18. View in: PubMed

  16. Actin filament bundling by fimbrin is important for endocytosis, cytokinesis, and polarization in fission yeast. J Biol Chem. 2011 Jul 29; 286(30):26964-77. View in: PubMed

  17. Characterization of engineered actin binding proteins that control filament assembly and structure. PLoS One. 2010 Nov 12; 5(11):e13960. View in: PubMed

  18. The stepping pattern of myosin X is adapted for processive motility on bundled actin. Biophys J. 2010 Sep 22; 99(6):1818-26. View in: PubMed

  19. Intracellular transport: force controls motor switching at filament junctions. Curr Biol. 2010 Jun 22; 20(12):R525-7. View in: PubMed

  20. Actin cross-link assembly and disassembly mechanics for alpha-Actinin and fascin. J Biol Chem. 2010 Aug 20; 285(34):26350-7. View in: PubMed

  21. Structured post-IQ domain governs selectivity of myosin X for fascin-actin bundles. J Biol Chem. 2010 Aug 20; 285(34):26608-17. View in: PubMed

  22. Unconventional processive mechanics of non-muscle myosin IIB. J Biol Chem. 2010 Aug 20; 285(34):26326-34. View in: PubMed

  23. A peptide tag system for facile purification and single-molecule immobilization. Biochemistry. 2009 Dec 22; 48(50):11834-6. View in: PubMed

  24. A new direction for titin pulling. Proc Natl Acad Sci U S A. 2009 Aug 11; 106(32):13149-50. View in: PubMed

  25. Fast benchtop fabrication of laminar flow chambers for advanced microscopy techniques. PLoS One. 2009 Aug 03; 4(8):e6479. View in: PubMed

  26. Mechanosensing through cooperative interactions between myosin II and the actin crosslinker cortexillin I. Curr Biol. 2009 Sep 15; 19(17):1421-8. View in: PubMed

  27. An engineered substance P variant for receptor-mediated delivery of synthetic antibodies into tumor cells. Proc Natl Acad Sci U S A. 2009 Jul 07; 106(27):11011-5. View in: PubMed

  28. Unconventional myosin traffic in cells reveals a selective actin cytoskeleton. Proc Natl Acad Sci U S A. 2009 Jun 16; 106(24):9685-90. View in: PubMed

  29. A myosin motor that selects bundled actin for motility. Proc Natl Acad Sci U S A. 2008 Jul 15; 105(28):9616-20. View in: PubMed

  30. The dual mode of action of bistramide A entails severing of filamentous actin and covalent protein modification. Proc Natl Acad Sci U S A. 2008 Mar 18; 105(11):4088-92. View in: PubMed

  31. A flexible domain is essential for the large step size and processivity of myosin VI. Mol Cell. 2005 Feb 18; 17(4):603-9. View in: PubMed

  32. Single molecule high-resolution colocalization of Cy3 and Cy5 attached to macromolecules measures intramolecular distances through time. Proc Natl Acad Sci U S A. 2005 Feb 01; 102(5):1419-23. View in: PubMed

  33. Myosin VI walks hand-over-hand along actin. Nat Struct Mol Biol. 2004 Sep; 11(9):884-7. View in: PubMed

  34. Dynacortin is a novel actin bundling protein that localizes to dynamic actin structures. J Biol Chem. 2002 Mar 15; 277(11):9088-95. View in: PubMed

  35. A crossbridge too far. Nat Cell Biol. 2002 Jan; 4(1):E8-10. View in: PubMed

  36. Myosin VI is a processive motor with a large step size. Proc Natl Acad Sci U S A. 2001 Nov 20; 98(24):13655-9. View in: PubMed

  37. A myosin II mutation uncouples ATPase activity from motility and shortens step size. Nat Cell Biol. 2001 Mar; 3(3):311-5. View in: PubMed

  38. In vitro assays of processive myosin motors. Methods. 2000 Dec; 22(4):373-81. View in: PubMed

  39. Myosin-V stepping kinetics: a molecular model for processivity. Proc Natl Acad Sci U S A. 2000 Aug 15; 97(17):9482-6. View in: PubMed

  40. Myosin-V is a processive actin-based motor. Nature. 1999 Aug 05; 400(6744):590-3. View in: PubMed

  41. Roux B, ed. Molecular Machines. Muscle and myosin. 2011; 99-114.::::

  42. Lennarz WJ, Lane MD, ed. The Encyclopedia of Biological Chemistry. Cytoskeletal motors: general principles. 2013; 3:632-635.::::

  43. Preparation of a water-soluble cage based on 3,5-dimethoxybenzoin. J Am Chem Soc. 1998; 120:10766-10767.::::

  44. Synthesis and photolysis properties of a photolabile linker based on 3’-methoxybenzoin. J Org Chem. 1996; 61(4):1526-1529.::::

  45. Efficient synthesis of photolabile alkoxy benzoin protecting groups. Tetr Lett. 1996; 37(3):307-310.::::

  46. Ha T, Selvin PR, ed. Single Molecule Techniques: A Laboratory Manual. Optical traps to study properties of molecular motors. 2007; 279-296.::::

  47. Hackney DD, Tamanoi F, ed. The Enzymes. The mechanics of unconventional myosins. 2003; 23:55-87.::::

  48. Rapid photochemical triggering of protein unfolding in a nondenaturing environment. Chem Phys. 2004; 307(2):201-208.::::

  49. A method for photoinitiating protein folding in a nondenaturing environment. J Am Chem Soc. 2000; 122:11567-11568.::::