Intermediate filaments (IF) are major cytoskeletal systems of vertebrate and many nonvertebrate cells whose expression is cell-type specific and developmentally regulated. This protocol describes the x-rhodamine labeling of one type of IF, vimentin, and a method for microinjection of the labeled vimentin into cultured cells. IF dynamics can then be examined with fluorescence microscopy. - [Read Preparation and Microinjection of x-Rhodamine-Labeled Vimentin Protocol]
Protocol reproducibly generates competent cultures of E. coli that yield 1 x 108 to 3 x 108 transformed colonies/µg of plasmid DNA. The protocol works optimally when the bacterial culture is grown at 18°C. If a suitable incubator is not available, a standard bacterial shaker can be set up in a 4°C cold room and regulated to 18°C. - [Read Preparation and Transformation of Competent E. Coli: "Ultra-Competent" Cells Protocol]
Protocol reproducibly generates competent cultures of E. coli that yield 1 x 108 to 3 x 108 transformed colonies/µg of plasmid DNA. The protocol works optimally when the bacterial culture is grown at 18°C. If a suitable incubator is not available, a standard bacterial shaker can be set up in a 4°C cold room and regulated to 18°C. - [Read Preparation and Transformation of Competent E. Coli: "Ultra-Competent" Cells Protocol]
Intermediate filaments (IF) are major cytoskeletal systems of vertebrate and many nonvertebrate cells whose expression is cell-type specific and developmentally regulated. This protocol describes a method for purifying one type of IF, vimentin, from bovine lens tissue. Purification of human vimentin expressed in Escherichia coli is also described. These methods are useful in the preparation of other IF protein subunits for microinjection studies as well. - [Read Purification of Bovine Lens and Bacterially Expressed Human Vimentin Protocol]
This protocol uses mitogen-activated protein/ERK kinase (MEK) to activate the extracellular-signal-regulated (Erk) mitogen-activated protein (MAP) kinases upon agonist binding to receptors. Protocol includes information about: Harvest, Immunoprecipitation and Kinase Reaction. Also includes following solutions: Laemmli Sample Buffer (1X), ATP Mix, Kinase Buffer (10X), Lysis Buffer. Helpful protocol hints are also included. - [Read Raf-1 Kinase Assay]
Protocol uses an autoregulatory system in which the transcriptional trans-activator tTA drives its own expression and that of a target gene. The first stage of the procedure describes how to generate stable lines of NIH-3T3 cells that express either tTA alone or tTA and the tetracycline-regulated target gene. - [Read Tetracycline as Regulator of Inducible Gene Expression Protocol]