On Thursday (26.03) we will host Prof. Lars Jansen (Dept. of Biochemistry, University of Oxford). His lecture will be entitled: "Remembering past infections through epigenetic transcriptional memory". The lecture will take place at 3 p.m. in the CN lecture hall and it will be followed by a get together.

Abstract:

Cells have evolved ways of remembering the past. A key example of such cellular memory is a fascinating phenomenon known as “Transcriptional Memory”. Here, a transient external signal induces a heritable cellular state that results in enhanced gene expression upon a future re-encounter with the inducing signal. This effect is widely observed across species, and in humans, it is specifically induced by innate immune signals and cytokines.

We discovered a unique class of gene clusters that are primed upon exposure to the key cytokine, interferon-gamma (IFNγ), that transiently activates inflammation and innate immune programs. These genes retain a memory of prior IFNγ exposure, which is mitotically heritable for weeks, even in rapidly proliferating cells. The mechanism of this unusual form of epigenetic memory is poorly understood, but we recently discovered that the primed state is propagated in the complete absence of target gene expression and is independent of activating transcription factors. Instead, cells establish a unique chromatin signature during priming that is heritably maintained and functionally required for future hyperactivation. Our findings provide insight into the chromatin basis for the long-term transcriptional memory of IFNγ signalling, which may contribute to enhanced innate immunity in vivo.