Abstract: A hand-held illuminated presentation pointer is described. In a lighted room, the pointer has all of the advantages of a conventional pointing rod. In a darkened room, the pointer can be illuminated so that it emits light from just one side of the shaft. When used in conjunction with a projected image such as from a 35 mm slide, the pointer is held so that illuminated side of the shaft faces the audience, with the result that the pointer is clearly visible as a glowing line in front of the projected image, and yet the appearance of the image is unaffected. Smaller illuminated pointers for use at close range are also described.

Abstract: The invention described here is a method whereby a molecular tag is put on a gene, transcript and protein in a single recombinational event. The protein tag takes the form of a unique peptide that can be recognized by an antibody or other specific reagent, the transcript tag takes the form of the sequence of nucleotides encoding the peptide that can be recognized by a specific polynucleotide probe, and the gene tag takes the form of a larger sequence of nucleotides that includes the peptide-encoding sequence and other associated nucleotide sequences. The central feature of the invention in its essential form is that the tag-creating DNA has a structure such that when it is inserted into an intron within a gene it creates two hybrid introns separated by a new exon encoding the protein tag. A major virtue of the method is that it allows one to identify new proteins or protein-containing structures, and, having done so, to readily identify and analyze the genes encoding those proteins.