Reprogramming a somatic nucleus by trans-modification activity in germ cells.
The germ cell lineage is totipotent insofar as it provides a link between an individual and the subsequent generations. There is a series of characteristic genomic modifications in germ cells that distinguish this lineage from somatic cells. These modifications include extensive demethylation of the genome, erasure of allele-specific methylation of imprinted loci and re-activation of the silent X chromosome. To test if this is an active process capable of reprogramming a somatic nucleus, we prepared germ cell-somatic cell hybrids. A dominant trans modification activity was detected in germ cells that was capable of inducing similar modifications in the somatic nucleus. This experimental system can therefore be used to study how determined cell state can be reversed by specific genomic modifications.
Surani
M A
MA
Wellcome CRC Institute of Cancer and Developmental Biology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QR, UK.
D000818:Animals; D002459:Cell Fusion; D002460:Cell Line; D019070:Cell Lineage / Q000235:genetics; D002467:Cell Nucleus / Q000235:genetics*; D019175:DNA Methylation; D018507:Gene Expression Regulation, Developmental; D018392:Genomic Imprinting; D005854:Germ Cells / Q000166:cytology / Q000378:metabolism*; D006822:Hybrid Cells / Q000166:cytology / Q000378:metabolism*; D008214:Lymphocytes / Q000166:cytology; D051379:Mice; D009865:Oocytes / Q000166:cytology