From 01/12/2022 To 01/12/2022

Starts at 16:00 until 17:00

17th Web seminar: ‘Epigenetics and Metabolism’

  • Address: Virtual
  • Language: English
  • Registration necessary: No

Dear All,

It is with great pleasure that we announce Prof. Michael O. Hottiger, Full Professor at the University of Zurich, Switzerland, who will give a virtual talk on December 1st at 16:00 CET titled “Mitochondrial NAD+ levels influence nuclear PARP1-induced ADP-ribosylation and subsequently the DNA damage response”. The following are the specifics of his presentation:    

Speaker: Prof. Michael O. Hottiger, University of Zurich, Switzerland

Talk: Mitochondrial NAD+ levels influence nuclear PARP1-induced ADP-ribosylation and subsequently the DNA damage response

Location: On Zoom (Meeting ID: 867 4943 1922; Passcode: 64199593).
Free registration Link:    

Abstract: In addition to its role as an electron transporter, mitochondrial nicotinamide adenine dinucleotide (NAD+) is an important co-factor for protein ADP-ribosylation. We provide evidence that knockdown of the mitochondrial NAD+ transporter SLC25A51 decreased the NAD+ concentration in mitochondria but increased the NAD+ concentration in the cytoplasm and nucleus. This NAD+ redistribution restrained mitochondrial function and energy metabolism but increased PARP1-mediated nuclear ADP-ribosylation and allowed a faster repair of DNA lesions. Similarly, H2O2-induced oxidative stress induced strong nuclear ADP-ribosylation, but reciprocally reduced mitochondrial NAD(H) levels. In contrast, elevation of mitochondrial NAD(H) by mitochondrial electron transport chain dampened H2O2-triggered nuclear ADP-ribosylation and increased MMS-induced PARP1 chromatin retention. Together, our results suggest that subcellular NAD+ availability regulates different cellular processes in a dynamic manner and provides evidence for a NAD+-mediated mitochondrial-nuclear crosstalk.

Biography: Michael O. Hottiger (Prof. DVM, PhD), studied at the University of Zurich. He then moved to the Howard Hughes Medical Institute at the University of Michigan (Ann Arbor, USA) before accepting 1998 a position as principal investigator at the University of Zurich (UZH). He was subsequently promoted first to associated professor for biochemistry and molecular biology in 2001, and in 2007 to full professor at the Department of Molecular Mechanisms of Disease (UZH). Since 2014 he is chair of the department. He is also co-founder and board member of DUALSYSTEMS Biotech AG. With his group he substantially contributed to our current understanding of protein ADP-ribosylation.