1Biochemistry and Molecular Biology, Colorado State University
A method is presented for the reconstitution of model nucleosomal arrays from recombinant core histones and tandemly repeated nucleosome positioning DNA. We also describe how sedimentation velocity experiments in the analytical ultracentrifuge, and atomic force microscopy (AFM) are used to monitor the extent of nucleosomal array saturation after reconstitution.
Published September 10, 2013. Keywords: Cellular Biology, Chromosome Structures, Chromatin, Nucleosomes, Histones, Microscopy, Atomic Force (AFM), Biochemistry, Chromatin, Nucleosome, Nucleosomal Array, Histone, Analytical Ultracentrifugation, Sedimentation Velocity
1Department of Cell and Developmental Biology, University of Pennsylvania, 2Biomedical Graduate Studies, University of Pennsylvania, 3Department of Animal Biology and Center for Animal Transgenesis and Germ Cell Research, University of Pennsylvania, 4Department of Genetics, University of Pennsylvania, 5Department of Biology, University of Pennsylvania
The STA-PUT method allows for the separation of different populations of spermatogenic cells based on size and density.
Published October 9, 2013. Keywords: Cellular Biology, Developmental Biology, Spermatogenesis, STA-PUT, cell separation, Spermatogenesis, spermatids, spermatocytes, spermatogonia, sperm, velocity sedimentation
1National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Dynamics of Macromolecular Assembly, Laboratory of Bioengineering and Physical Science
The analytical ultracentrifuge (AUC) sample cell holds sample and reference buffer and during experiments and is exposed to high vacuum and rotor speeds up to 60,000 rpm. This video will demonstrate the rigorous attention to detail necessary for assembly, loading and alignment of this very important component of an AUC experiment.
Published November 5, 2009. Keywords: Basic Protocols, analytical ultracentrifugation, sedimentation velocity, sedimentation equilibrium, protein characterization, sedimentation coefficient
1Departamento de Biología Molecular, Instituto de Investigaciones Biológicas Clemente Estable (IIBCE), 2Servicio de Citometría de Flujo y Clasificación Celular (SECIF), Instituto de Investigaciones Biológicas Clemente Estable, 3Sección Bioquímica, Facultad de Ciencias, Universidad de la República
A novel protocol for the mechanical preparation of testicular cell suspensions from rodent material, avoiding enzymes and detergents, is described. The method is very simple, fast, reproducible, and renders good quality cell suspensions, which are suitable for flow sorting and RNA extraction.
Published August 4, 2013. Keywords: Cellular Biology, Medicine, Biomedical Engineering, Anatomy, Physiology, Cell Separation, Flow Cytometry, Cytological Techniques, Meiosis, Spermatogenesis, Cell Biology, Flow cytometry, FACS, testis, meiosis, cell suspension, rodent, cell culture, animal model
1Genome Plasticity Laboratory, Department of Cancer Biology, The Scripps Research Institute, 2Flow Cytometry Core, The Scripps Research Institute
An efficient method to obtain highly purified viable meiotic fractions from mouse testis is described, which combines a refined cell dissociation protocol with fluorescent activated cell sorting (FACS). This method takes advantage of differences in the DNA content and nuclear density of discrete meiotic fractions.
Published April 15, 2011. Keywords: Cellular Biology, meiosis, mouse, FACS, purification, testis