COLD SPRING HARBOR, N.Y. (Tues., June 1, 2010) -- Gel electrophoresis is one of the most important and frequently used techniques in RNA analysis. Electrophoresis is used for RNA detection, quantification, purification by size and quality assessment. Gels are involved in a wide variety of methods including northern blotting, primer extension, footprinting and analyzing processing reactions. The two most common types of gels are polyacrylamide and agarose. Polyacrylamide gels are used in most applications and are appropriate for RNAs smaller than approximately 600 nucleotides (agarose gels are preferred for larger RNAs). "Polyacrylamide Gel Electrophoresis of RNA" describes how to prepare, load and run polyacrylamide gels for RNA analysis. The article is featured in the June issue of Cold Spring Harbor Protocols and is freely available on the journal's website. It is part of a suite of basic RNA protocols included in this month's issue that provide an early preview of the forthcoming RNA: A Laboratory Manual due later this year from Cold Spring Harbor Laboratory Press.
The rapid pace of technological progress in biological imaging has provided great insight into the processes of embryonic development. But for higher organisms with opaque eggs or internal development, optical access to the embryo is limited. While various embryonic culture methods are available, vertebrate development is best studied in an intact embryo model, one in which the natural environment has not been disrupted. In the June issue of Cold Spring Harbor Protocols, Paul Kulesa and colleagues from the Stowers Institute for Medical Research present "In Ovo Live Imaging of Avian Embryos," a detailed set of instructions for time-lapse imaging of fluorescently labeled cells within a living avian embryo. During the procedure, a hole is made in the shell, and a Teflon membrane that is oxygen-permeable and liquid-impermeable is used to provide a window for visualization of the embryo via confocal or two-photon microscopy. Imaging can take place for up to five days without dehydration or degradation of the normal developmental environment. As one of June's featured articles, the protocol is freely available on the journal's website.