If fused to a protein the subcellular location can be observed and changes in localization in response to signals can be monitored over time. 1. coding regions from different proteins can be joined together. If the reading frame is maintained functional proteins can be synthesized from them in vitro or in vivo. 1. site-directed mutagenesis can be accomplished using oligonucleotides to change one or several bases. F. Transgenic analysis 1.
Many approaches make use of transgenic organisms.
These methods are extremely powerful because we can now put reporter gene constructs, fusion protein constructs, or mutagenized sequences into the organism. These approaches can also be used to generate knock-outs. Complementation of existing mutants or examination of the expression of a known gene in mutants can demonstrate the function of a cloned sequence. Their haploid genomes also facilitate analysis. Gene addition can be used to insert genes that yield antisense RNA molecules.