Horizontální přenos genů a genové inženýrství vyústily v celou řadu případů, kdy došlo k překročení hranic oddělujících lidský genom od genomů jiných organismů. Horizontální přenos genů je ryze přírodní proces, který nedokážeme potlačit. Genové inženýrství je vys- oce prospěšná lidská aktivita, jíž se nemůžeme vzdát. Navíc se ukazuje, že naši předci „pošpinili“ náš genom sekvencemi několika vymřelých druhů člověka. Je proto nezbytné přijmout jako fakt, že hranice lidského genomu nejsou jasně vytyčené a že v budoucnu budou jeho obrysy ještě nejasnější., The horizontal gene transfer and genetic engineering resulted in many crossings of the boundary dividing the human genome from the genomes of other organisms. The horizontal gene transfer is a natural process and cannot be stopped. The genetic engineering is a highly beneficial human activity and we cannot abandon it. Moreover, our ancestors “spilled” our genome with sequences of DNA from seve- ral extinct human species. It is necessary to accept that the border of the human genome is not sharply delineated. In the future, the contours of our genome could become even much fuzzier., Jaroslav Petr, and Literatura
Granulosa cells (GCs) are somatic cells essential for establishing and maintaining bi-directional communication with the oocytes. This connection has a profound importance for the delivery of energy substrates, structural components and ions to the maturing oocyte through gap junctions. Cumulus cells, group of closely associated GCs, surround the oocyte and can diminished the effect of harmful environmental insults. Both GCs and oocytes prefer different energy substrates in their cellular metabolism: GCs are more glycolytic, whereas oocytes rely more on oxidative phosphorylation pathway. The interconnection of these cells is emphasized by the fact that GCs supply oocytes with intermediates produced in glycolysis. The number of GCs surrounding the oocyte and their age affect the energy status of oocytes. This review summarises available studies collaboration of cellular types in the ovarian follicle from the point of view of energy metabolism, signaling and protection of toxic insults. A deeper knowledge of the underlying mechanisms is crucial for better methods to prevent and treat infertility and to improve the technology of in vitro fertilization.