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The Kumar Laboratory

Welcome to the home page of the Kumar Laboratory in the Department of Bioengineering at the University of California, Berkeley!

We address problems in molecular cell dynamics and mechanics, with a focus on understanding how the cellular cytoskeleton governs cellular structure and senses and transduces mechanical inputs from the extracellular environment. We are especially interested in exploring these issues in the nervous system, including neuronal and glial tumors and adult neural stem cells. We take both "inside-out" and "outside-in" approaches, including: (1) Studying and manipulating the microscale assembly and mechanics of cytoskeletal networks in reconstituted and live-cell preparations; and (2) Fabricating extracellular matrices that present defined biophysical cues to cells and determining how these cues influence cell physiology. Our work takes advantage of optical and atomic force microscopy, subcellular laser ablation and photobleaching, microfabrication, traditional biochemical and cell biological methods, and computational tools.

An increasing number of micro- and nanotechnologies either subject cells to mechanical forces, require cells to be patterned into specific spatial arrangements, or both, including a wide variety of MEMS and microfluidic devices and tissue engineering systems. Moreover, many disease states are characterized by altered biophysical crosstalk between cells and their environment. Thus, in addition to building a fundamental understanding of cellular mechanobiology, we envision applying what we learn to contribute to the rational design of cellular biotechnology and to the development of new forms of therapy.

News and Announcements

April 2017: Congratulations to George on receiving an Outstanding Graduate Student Instructor Award from the UC Berkeley Teaching & Resource Center!

April 2017: The lab welcomes Pierre Nedelec, a visiting student from École Polytechnique (France).

April 2017: Congratulations to George on winning a travel award to attend and present at the Biophysical Society Thematic Meeting on Single-Cell Biophysics in Taiwan in June!

March 2017: We have a new publication in Stem Cells in collaboration with Schaffer Lab at UC Berkeley: Rammensee, Kang et al., Dynamics of Mechanosensitive Neural Stem Cell Differentiation. 

February 2017: Congratulations to Ruoxing for passing her qualifying exam and advancing to Ph.D. candidacy!

February 2017: We have a new publication in PNAS in collaboration with Ulrich Schwarz’s lab at the University of Heidelberg: Kassianidou et al., Geometry and network connectivity govern the mechanics of stress fibers.

January 2017: Stacey is awarded an NIH NRSA (F31) Predoctoral Fellowship. Congratulations!

November 2016: We have a new publication in Biophysical Journal in collaboration with the Muller Lab at UCB and the Husson and Barakat Labs at École Polytechnique in France: Guillou, Dahl, Lin et al., Measuring cell viscoelastic properties using a microfluidic extensional flow device.

October 2016: Recent visitor Jieung Baek wins the student oral competition at the Korean Society for Biomaterials meeting for the work she did with us on controlling neural stem cell differentiation with 3D biomaterials.  Congratulations!   

October 2016: Recent visitor Anne-Lou Roguet wins a Grand Prize for Research at Ecole Polytechnique (France) for the work she did with us on geometric regulation of stress fibers.  Congratulations!

September 2016: We have a new publication in F1000 Faculty Reviews: Lee and Kumar, Actomyosin stress fiber mechanosensing in 2D and 3D.

August 2016: The lab bids farewell to Joanna Bechtel Dahl, who is moving on to a faculty position in the Department of Engineering at UMass Boston.  Congratulations and good luck, Professor!

July 2016: Sanjay is elected a Fellow of the Biomedical Engineering Society (BMES).  Details here.

June 2016: Congratulations to Ari (Arezou) for receiving a Staff Appreciation and Recognition (STAR) Achievement Award from the UC Berkeley campus!   

June 2016: We have a new publication in Biomaterials in collaboration with the Francis Lab at UCB: Lee et al., N-terminal Specific Conjugation of Extracellular Matrix Proteins to 2-Pyridinecarboxaldehyde Functionalized Polyacrylamide Hydrogels

May 2016: We have a new publication in Langmuir in collaboration with the Weaver Lab at UCSF: Bhagawati et al., Site-specific modulation of charge controls the structure and stimulus-responsiveness of intrinsically disordered peptide brushes

May 2016: We have a new publication in Current Opinion in Biotechnology: Hughes and Kumar, Synthetic mechanobiology: Engineering cellular force generation and signaling.  

May 2016: Congratulations to Jess Lee on completing her Ph.D.! We wish her the very best as she starts her new position in the Polymer Science and Materials Chemistry Practice at Exponent.

April 2016: Congratulations to Elena on being named a 2016-17 Siebel Scholar and to Stacey for being named a 2016-17 Lloyd Scholar by the Bioengineering PhD program!  

April 2016: We have a new publication in Royal Society Open Science in collaboration with the Schaffer Lab: Luque, Kang et al., Microelastic mapping of the rat dentate gyrus.

March 2016: Congratulations to former PhD student Anuj Patel on his new position at DiCE Molecules!

March 2016: We are pleased to welcome three visiting scholars to the lab: Olivier Venzin (EPFL, Switzerland), Jieung Baek (KAIST, Korea), and Anne-Lou Roguet (Ecole Polytechnique, France). 

March 2016: We have a new publication in Soft Matter in collaboration with the Muller Lab and the Shaqfeh Lab (Stanford): Dahl et al., Experimental Observation of the Asymmetric Instability of Intermediate-Reduced-Volume Vesicles 

February 2016: Congratulations to Phil for passing his qualifying exam and advancing to Ph.D. candidacy!

January 2016: Our 2013 Integrative Biology paper on co-regulation of invasive migration by transforming potential and matrix stiffness receives a two-star recommendation in Faculty of 1000.

January 2016: We have a new publication in Current Biology in collaboration with the Butcher Lab at Cornell: Gould et al., Cyclic mechanical loading is essential for Rac1-mediated elongation and remodeling of the embryonic mitral valve.

December 2015: Congratulations to Stacey for passing her qualifying exam and advancing to Ph.D. candidacy!

November 2015: The lab is pleased to welcome Ruoxing Lei, a first-year Chemistry PhD student!

November 2015: Congratulations to former postdoc Nithya Srinivasan on her new position at Cynvenio Biosystems!

November 2015: Congratulations to former PhD student Joanna MacKay on her new position at Janssen R&D!

September 2015: We have a new publication in Scientific Reports: Chang and Kumar, Differential Contributions of Nonmuscle Myosin II Isoforms and Functional Domains to Stress Fiber Mechanics.

September 2015: We have a new publication in Nature Communications in collaboration with the Murthy Lab: Rape et al., A synthetic hydrogel for the high-throughput study of cell–ECM interactions.  Read the announcement here.

August 2015: We have a new publication in Gene Therapy in collaboration with the Schaffer Lab and others: Santiago-Ortiz et al., AAV ancestral reconstruction library enables selection of broadly infectious viral variants.  

August 2015: Badri departs to begin his new position as a Research Scientist at Benitec Biopharma.  Congratulations and best wishes!

July 2015: Sanjay is appointed Associate Chair of the Department of Bioengineering.

July 2015: The lab warmly welcomes new postdoctoral fellow Joe Chen, Ph.D., from Vanderbilt!

July 2015: The lab bids farewell to Andy Rape and wishes him the best in his new position as Co-Founder and Creative Director of A519.

July 2015: Congratulations to Elena on receiving a travel award to attend and present her work at PhysCell 2015 later this summer!

July 2015: The NIH appoints Sanjay to a four-year term as a Standing Member of the Intercellular Interactions (ICI) Study Section.

June 2015: Congratulations to George for receiving a 2015-2016 Cancer Research Coordinating Committee (CRCC) Predoctoral Fellowship!

May 2015: Congratulations to Sophie Wong and Yushan Kim on completing their Ph.D.’s!   We wish them the very best in their new positions at Simon-Kucher & Partners (Dr. Wong) and C1 Consulting (Dr. Kim). 

May 2015: Our research on intrinsically disordered protein-based materials is featured in Berkeley Engineer.

May 2015: Congratulations to former Ph.D. student Albert Keung, who will be joining the North Carolina State University Department of Chemical and Biomolecular Engineering as an Assistant Professor in January 2016!

May 2015: Kayla Wolf, a first-year Ph.D. student in Bioengineering, has joined the lab for her thesis research. Welcome, Kayla!

May 2015: Congratulations to Stacey Lee on receiving an Outstanding Graduate Student Instructor Award from the UC Berkeley Teaching & Resource Center!  Details here.

April 2015: We have a new publication in the Annual Review of Chemical and Biomolecular Engineering : Dahl, Lin, et al. Microfluidic strategies for understanding the mechanics of cells and cell-mimetic systems.

April 2015: Our recent Cancer Research study on GBM invasion, which was done in collaboration with the Reynolds Lab, is featured on the University of Florida website

April 2015: We have a new publication in BBA Molecular Cell Research: Kassianidou and Kumar, A biomechanical perspective on stress fiber structure and function.

March 2015: Congratulations to Mike for passing his qualifying exam and advancing to Ph.D. candidacy!

February 2015: Congratulations to former postdoc Ching-Wei Chang on his new position as a Staff Research Engineer in the Department of Electrical Engineering at Stanford!

February 2015: UC Berkeley’s Excellence in Research page profiles our lab’s cancer research.  Story here.

January 2015: Congratulations to George for passing his qualifying exam and advancing to Ph.D. candidacy!

January 2015: We have a new publication in Cancer Research in collaboration with the Reynolds Lab at U Florida: Wong et al., Constitutive activation of myosin-dependent contractility sensitizes glioma tumor-initiating cells to mechanical inputs and reduces tissue invasion.

January 2015: Congratulations to former postdoc Amit Pathak, now Assistant Professor of Mechanical Engineering and Materials Science at Washington University, on receiving the NSF CAREER Award!  Details here.

January 2015: Sanjay is elected to the American Institute for Medical and Biological Engineering (AIMBE).  Details here.

November 2014: Congratulations to Theresa Ulrich (PhD 2011) on her new position as Associate Director of Foundation Relations at MIT! 

October 2014: Our 2014 Molecular Cancer Reearch paper is featured as one of the highlights of the issue.

October 2014: We have a new publication in Nature Communications: Srinivasan et al., Stimuli-sensitive intrinsically disordered protein brushes.  Read the campus news story here and the Faculty of 1000 highlight here.

September 2014: We have a new publication in PNAS in collaboration with the Lam Lab at Georgia Tech/Emory: Qiu et al., Platelet mechanosensing of substrate stiffness during clot formation mediates adhesion, spreading, and activation.

September 2014: We have a new publication in Analytical Chemistry in collaboration with the Herr Lab: Kang et al., Single-cell western blotting after whole-cell imaging to assess cancer chemotherapeutic response.

September 2014: We have a News and Views piece in Nature Materials about recent efforts to decouple contributions of extracellular matrix stiffness from effects of ligand density and tethering.

September 2014: Congratulations to Sophie on being named a 2015 Siebel Scholar!  She is one of only 83 students nationally to receive this honor.   Details here.  

August 2014: Sebastian departs for the UK to start as a Consultant with The Technology Partnership.  Congratulations and best wishes!

July 2014: We have a new publication in Integrative Biology: MacKay and Kumar, Simultaneous and independent tuning of RhoA and Rac1 activity with orthogonally inducible promoters.

July 2014: We have a new publication in Biomaterials: Rape and Kumar, A composite hydrogel platform for the dissection of tumor cell migration at tissue interfaces.

July 2014: We have a new publication in PLOS ONE: Umesh et al., Microenvironmental stiffness enhances glioma cell proliferation by stimulating epidermal growth factor receptor signaling.

July 2014: Sanjay is promoted to Full Professor.  Many thanks to all who helped make it happen, especially past and present members of the lab. 

June 2014: We have a new publication in Molecular Cancer Research: Kim and Kumar, CD44-mediated Adhesion to Hyaluronic Acid Contributes to Mechanosensing and Invasive Motility.

June 2014: We have a new publication in Cell Reports in collaboration with the LaBarge Lab at LBNL: Pelissier et al., Age-related dysfunction in mechanotransduction impairs differentiation of human mammary epithelial progenitors.

June 2014: Congratulations to Jasmine for passing her qualifying exam and advancing to Ph.D. candidacy!

May 2014: Phil Kang and Stacey Lee, first-year Ph.D. students in
Bioengineering, have joined the lab for their thesis research.
Welcome, Phil and Stacey!

April 2014: Congratulations to Jasmine for receiving the Natural
Sciences and Engineering Research Council of Canada (NSERC)
Postgraduate Doctoral Scholarship!

March 2014: Sanjay receives support from the Raymond and Beverly Sackler Center Sabbatical Exchange Program for his activities at UCSF. Details here.

January 2014: We have a new publication in Science Translational Medicine: Kurpinski et al., Mastering Translational Medicine: Interdisciplinary Education for a New Generation.

January 2014: The lab is grateful to receive a research award from the W. M. Keck Foundation.  Details here.

November 2013: The lab is pleased to welcome Jessica (Jess) Lee, a Chemical Biology Ph.D. student who will be jointly advised by Prof. Matt Francis in Chemistry.

November 2013: We have a new publication in Soft Matter: MacKay et al., Three-dimensional patterning of multiple cell populations through orthogonal genetic control of cell motility.

October 2013: The lab is pleased to welcome Dr. Joanna Bechtel Dahl, an NSF Postdoctoral Research Fellow in Biology who will be jointly advised by Prof. Susan Muller in Chemical and Biomolecular Engineering.

October 2013: We have a new publication in Chemical Communications: Acharya et al., A fluorescent peroxidase probe increases the sensitivity of commercial ELISAs by two orders of magnitude.

August 2013: Congratulations to Elena on winning a Howard Hughes Medical Institute (HHMI) International Student Research Fellowship!  She was only one of 42 recipients nationally and will receive three years of significant financial support.  She is also featured prominently in the official HHMI press release and on the Berkeley BioE Department webpage.

July 2013: The lab is featured in a campus news story on the Amgen Scholars Program.





Archive of past news and announcements from the Kumar Lab

Lab Meeting Schedule

Resources for lab members

The Kumar Laboratory gratefully acknowledges grant support from the National Institutes of Health, the National Science Foundation, the Army Research Office, the Raymond and Beverly Sackler Center, and the W. M. Keck Foundation.  We also gratefully acknowledge predoctoral fellowship support from the National Science Foundation, Department of Defense, Natural Sciences and Engieneering Research Council of Canada, and Howard Hughes Medical Institute, and postdoctoral fellowship support from the California Institute for Regenerative Medicine and the National Institutes of Health.