An essential approach to understanding the mechanisms of development is to alter a gene function/expression. In vivo electroporation has been adapted as one such technique (Muramatsu et al., 1997). It is a very useful tool to achieve a gain- and loss-of-function (by using RNAi or morpholinos) of a gene of interest (Funahashi et al., 1999
Fukuchi-Shimogori and Grove, 2001
Kos et al., 2001
Katahira and Nakamura, 2003
Sugiyama and Nakamura, 2003). The technique has allowed the altering of gene expression temporally and spatially. Pulse-labeling technique is an approach to manipulate a specific cell population temporally, depending on its birthday, as this chapter describes. This technique is more advantageous over the BrdU application, as it can reveal cell lineage
it also has the ability to manipulate a gain- and loss-of-function into specific precursor cells (Tabata and Nakajima, 2001
Sugiyama and Nakamura, 2003
Huber et al., 2008). In spatial terms, widespread gene transfer by electroporation has provided an efficient way to unveil a new gene function on a given tissue (Nakamura and Funahashi, 2001). On the other hand, the spatial precision of gene transfer also has been addressed as each individual cell responds differently to gene expression. Thus, there has been increasing efforts to improve electrodes and create new techniques such as single-cell electroporation (Haas et al., 2001
Kitamura et al., 2008). © 2009 Springer Japan.