Xenopus helveticus, an endangered species?

This review traces the history of Xenopus research in Switzerland, its worldwide beginnings and British chapters having been summarised previously (Gurdon and Hopwood, 2000). As in other countries, Xenopus was initially used in the pharmaceutical industry at Basel for pregnancy testing. Developmental biologists became interested in this peculiar amphibian because it may be induced to ovulate all year round. Swiss Xenopus research is reviewed over 50 years, from the introduction of Xenopus by Rudolf Weber to the University of Bern, the return from Great Britain of two Swiss expatriates, Michail Fischberg and Max Birnstiel through the numerous pupils of the founder labs to the independently arisen Xenopus research units in the country. Besides developmental biology, Swiss Xenopus research engaged in immunology, genetics and cell biology, the latter focusing mainly on the oocyte. It set highlights in molecular biology by isolating some of the first eukaryotic genes and analysing their transcriptional regulation and post-transcriptional modifications through 'surrogate genetic' approaches in the oocyte system. An important line of research applied this system to study nuclear trafficking. Presently, functional testing mainly serves to characterise the function of proteins produced from expression vectors injected into the oocyte. A main accent of developmental studies was, from the early beginnings and still today, set on molecular characterisation of gene function in the embryo.