Seminars and Events

Past Events

Category Other
Date and Time 2018-01-30 15:00 - 16:00
Venue Seminar Room A7F
Speaker Yi Zhang
Affiliation Harvard Medical School
Title [IMS Seminar] Epigenetic and chromatin reprogramming at the beginning of mammalian life
Poster click here to download(PDF)
Host Hironobu Fujiwara
Summary Mammalian sperm and oocytes have different chromatin organization and epigenetic landscapes. Following fertilization, the protaminepackaged
sperm genome is assembled into chromatin de novo, while the maternal chromatin is inherited from the egg. During preimplantation development, both genomes go through reprogramming to become largely equal with the exception of imprinted loci. After global DNA demethylation, zygotic genome activation takes place to prepare the embryos for the first cell lineage specification and later embryonic development. Despite their importance, the molecular mechanism underlying these fundamental developmental processes are not well understood due to the technical difficulties in working with limited cell numbers. In the past several years, we have developed a number of techniques which allowed us to tackle these important yet technically challenge questions. In addition to reprogramming sperm, egg can also reprogramming somatic cells into totipotency. We identified a major epigenetic barrier for somatic cell nuclear transfer (SCNT)-based reprogramming and demonstrated that we can overcome this barrier to achieve high reprogramming efficiency, which has great potential for regenerative medicine. In the seminar, I will present our major discoveries that underlying mammalian preimplantation development and SCNT reprogramming, including the first TF important for ZGA and a new mechanism of genomic imprinting.