Microinjection experiments using cloned gene templates into fertilized eggs of Xenopus laevis provide an interesting experimental system to study factors involved in control of gene expression, as well as possible mechanisms of gene integration and rearrangements of injected DNA templates into the Xenopus genome. In addition, for many types of cloned genes it is possible to compare transcription characteristics obtained from an embryo injection experiment with results from gene-injected oocytes.
In the case of DNA injection experiments into Xenopus oocytes, systematic studies have been carried out on the stability and chromatin configuration of injected DNA following injection into the cytoplasm or into the nucleus (‘germinal vesicle’) of the large Xenopus oocyte. It was found that DNA can be injected into both cellular compartments, but that injected DNA is rapidly degraded after injection into the cytoplasm, whereas DNA injected into the nucleus of the oocyte is not degraded but assembled into...
