Transplantation of Xenopus laevis cell nucleus to enucleated Xenopus egg leads to the generation of cloned animal. This exemplifies the process of nuclear reprogramming by which the nucleus of a specialized cell is reset to an embryonic state from which it can generate all the cells of an organism. Using the precursor of the egg, the oocyte, it is also possible to reprogram somatic cell. The ad...

Mammalian oocytes possess fascinating unknown factors, which can reprogram terminally differentiated germ cells or somatic cells into totipotent embryos. Here, we demonstrate that oocyte-specific homeobox 1 (Obox1), an oocyte-specific factor, can markedly enhance the generation of induced pluripotent stem cells (iPSCs) from mouse fibroblasts in a proliferation-independent manner and can replace...

The specific molecular mechanisms involved in somatic reprogramming remain unidentified. Removal of the oocyte genome is one of the primary causes of developmental failure in cloned embryos, whereas intact oocyte shows stronger reprogramming capability than enucleated oocyte. To identify the reason for the low efficiency of cloning and elucidate the mechanisms involved in somatic reprogramming ...

Background: Since the sheep ‘Dolly’ was successfully cloned by somatic cell nuclear transfer (SCNT), the inefficiency of SCNT cloning and abnormality of cloned animals have been a focus of considerable controversy. Oocyte quality has been shown to contribute to poor somatic cloning and cell reprogramming efficiency with many factors affecting oocyte quality and developmental potential. It has b...

The birthrate following round spermatid injection (ROSI) remains low in current and evidence suggests that factors in the germinal vesicle (GV) cytoplasm and certain substances in the GV such as the nucleolus might be responsible for genomic reprogramming and embryonic development. However, little is known whether the reprogramming factors in GV oocyte cytoplasm and/or nucleolus in GV are benef...

While reprogramming a foreign nucleus after somatic cell nuclear transfer (SCNT), the enucleated oocyte (ooplasm) must signal that biomass and cellular requirements changed compared to the nucleus donor cell. Using cells expressing nuclear-encoded but mitochondria-targeted EGFP, a strategy was developed to directly distinguish maternal and embryonic products, testing ooplasm demands on transcri...

objective: induced pluripotent stem cells are generated from somatic cells by direct reprogramming. these reprogrammed pluripotent cells have different applications in biomedical fields such as regenerative medicine. although viral vectors are widely used for efficient reprogramming, they have limited applications in the clinic due to the risk for immunogenicity and insertional mutagenesis. acc...

Multiple sclerosis (MS) is one of the most common neuroinflammatory disorders that causes disability in the young adults. In this disease immune-driven demyelination and following that inefficient remyelination occurs. Therapies for this disease are limited, especially those to enhance myelin repair. Cellular reprogramming using defined genetic factors is a way to produce remyelinating Oligoden...

Background The metabolic state of a cell is an important factor in whether or not it engages its apoptotic machinery. Furthermore, reprogramming energy metabolism is now recognized as a hallmark of cancer; so understanding how metabolism regulates apoptosis is crucial. Recently it has been demonstrated that CaMKII serves as a link between metabolic state and apoptosis [1]. Using the Xenopus lae...

When transplanted into Xenopus oocytes, the nuclei of mammalian somatic cells are reprogrammed to express stem cell genes such as Oct4, Nanog, and Sox2. We now describe an experimental system in which the pluripotency genes Sox2 and Oct4 are repressed in retinoic acid-treated ES cells but are reprogrammed up to 100% within 24 h by injection of nuclei into the germinal vesicle (GV) of growing Xe...