Histone variant H3.3 is an essential maternal factor for oocyte reprogramming

Abstract

Significance A differentiated cell nucleus can be reprogrammed into the pluripotent state by maternal factors in ooplasm; the factors that are responsible for this reprogramming process have not yet been identified. In this paper, we show that histone variant H3.3 is one of the essential maternal factors involved in somatic nuclear reprogramming. Maternal H3.3, not H3.3 in the donor chromatin, is required for development and the reactivation of many key pluripotency genes in somatic cell nuclear transfer (SCNT) embryos. H3.3 facilitates reprogramming by remodeling the donor nuclear chromatin through replacement of donor H3 in chromatin with de novo synthesized maternal H3.3 at the beginning of reprogramming in SCNT embryos.