Old Dominion University

4 ARTICLES PUBLISHED IN JoVE

Behavior

Experimental Assessment of Mouse Sociability Using an Automated Image Processing Approach

Frency Varghese¹, Jessica A. Burket², Andrew D. Benson², Stephen I. Deutsch², Christian W. Zemlin¹

¹Department of Electrical and Computer Engineering and Frank Reidy Center for Bioelectrics, Old Dominion University, ²Department of Psychiatry & Behavioral Sciences, Eastern Virginia Medical School

This protocol describes a method to quantify mouse sociability. Mice are videotaped as they move and interact in a special cage. Movie processing allows for the automated quantification of sociability with excellent accuracy and reliability.

Bioengineering

Stiffness Measurement of Soft Silicone Substrates for Mechanobiology Studies Using a Widefield Fluorescence Microscope

Yashar Bashirzadeh^*1, Siddharth Chatterji^*1, Dakota Palmer^*2, Sandeep Dumbali^*1, Shizhi Qian¹, Venkat Maruthamuthu¹

¹Department of Mechanical & Aerospace Engineering, Old Dominion University, ²Department of Biological Sciences, Old Dominion University

Substrates with stiffness in the kilopascal-range are useful to study the response of cells to physiologically relevant micro-environment stiffness. Using just a widefield fluorescence microscope, the Young's modulus of soft silicone gels can be determined using an indentation with a suitable sphere.

Immunology and Infection

A Purification and In Vitro Activity Assay for a (p)ppGpp Synthetase from Clostridium difficile

Astha Pokhrel¹, Asia Poudel¹, Erin B. Purcell¹

¹Department of Chemistry and Biochemistry, Old Dominion University

Here, we describe a method for purifying histidine-tagged pyrophosphokinase enzymes and utilizing thin layer chromatography of radiolabelled substrates and products to assay for the enzymatic activity in vitro. The enzyme activity assay is broadly applicable to any kinase, nucleotide cyclase, or phosphor-transfer reaction whose mechanism includes nucleotide triphosphate hydrolysis.

Bioengineering

Rapid Encapsulation of Reconstituted Cytoskeleton Inside Giant Unilamellar Vesicles

Yashar Bashirzadeh^*1, Nadab Wubshet^*1, Thomas Litschel², Petra Schwille³, Allen P. Liu^1,4,5,6

¹Department of Mechanical Engineering, University of Michigan, Ann Arbor, ²John A. Paulson School of Engineering and Applied Sciences, Harvard University, ³Department of Cellular and Molecular Biophysics, Max Planck Institute of Biochemistry, ⁴Department of Biomedical Engineering, University of Michigan, Ann Arbor, ⁵Department of Biophysics, University of Michigan, Ann Arbor, ⁶Cellular and Molecular Biology Program, University of Michigan, Ann Arbor

This article introduces a simple method for expeditious production of giant unilamellar vesicles with encapsulated cytoskeletal proteins. The method proves to be useful for bottom-up reconstitution of cytoskeletal structures in confinement and cytoskeleton-membrane interactions.