Investigators can utilize X chromosome inactivation (methylation) to determine the clonality status of a tumor or premalignant lesion in females. The technique is based on a methylation-sensitive restriction enzyme and analysis of a polymorphic locus on the X chromosome. Clonal cell populations will show "loss" of the non-methylated allele after restriction digest. The assay can be performed on DNA recovered from microdissected samples. Both frozen tissue and fixed-embedded tissue can be used. - [Read Clonality - X Chromosome Inactivation Assay Protocol]
How to Use Asci for Obtaining Double Mutants- http://www.fgsc.net/neurosporaprotocols/How%20to%20use%20asci%20for%20obtaining%20double%20mutants%20of%20genes%20that%20show%20epistasis%20of%20are%20phenotypically%20similar.pdf
Frozen tissue sections show good preservation of tissue structure and antigens. The principle disadvantages of using them in immunostaining are that the specimens must be stored frozen, and a special microtome, known as a cryostat, is required. Also, many clinical specimens are not available in this form, and most classic histological descriptions of tissue structure and pathology are based on the use of paraffin-embedded sections of formalin-fixed material. - [Read Preparing Frozen Tissue Sections for Immunostaining Protocol]
This procedure was first described by Bertrand et al to demonstrate that ribozymes could be enzymatically active in vivo. We adapted the method to show that certain oligodeoxynucleotides could direct the activity of endogenous ribonuclease H to cleave tar - [Read Reverse Ligation Mediated RT - PCR]
Human embryonic stem cells are a valuable resource for research and cell replacement therapy but are notoriously cumbersome to culture. Bhatia and colleagues show that an increased dose of basic fibroblast growth factor eliminates the need for feeder laye - [Read Simplifying hESC culture]
Describes how FACSort can be used to enrich for transfected mouse cells expressing high levels of the human thrombin receptor. The sorted fraction can then be cultured in vivo and reanalyzed 12 days later to show that it remains enriched for thrombin receptor-expressing cells. - [Read Sorting Transfected Cells Based on Gene Expression, Followed by Culture in Vivo]