Wykorzystanie linii komórkowych i metod synchronizacji cyklu komórkowego w klonowaniu ssaków

Studies aimed at improving the effectiveness of cloning by nuclear transfer have shown thatproper development of the majority of reconstituted embryos is secured by G1 phase of thedonor nucleus or by using “universal recipients” i.e. enucleated pre-activated oocytes. Donornuclei for cloning may be derived from cell lines of embryonic stem cells (mouse), embryoniccells after short in vitro culture (sheep, pig, cattle) or even from fetal cells or adult cells afterin vitro culture and inducing quiescence in their nuclei (sheep).The use of fetal cells for transgenesis in vitro and the production of transgenic sheep afternuclear transfer from these cells opens the way to profitable technology of cloning transgenicfarm animals.