IBMB Seminar, Friday, July 14th 10:00 AM | IAN JAMES HOLT, PHD

Date: Friday, July 14th | Fèlix Serratosa | 14|07|2023

Time: 10:00 AM

Speaker: Ian James Holt.
PhD. Mitochondria Health and Aging, Department of Neuroscience, Biodonostia Research Institute (San Sebastián, Spain)

Title: “The AAA+ protein ATAD3 lifts the lid on the Mitochondrial-Cholesterol Axis“

Seminar Room: Fèlix Serratosa

Keywords: Mitochondrial disease, cholesterol, cholesterol aggregation and disease, membrane recycling, lysosomes, ATAD3, AAA⁺ ATPase, Lysosomal storage disorders

Biosketch:

Ian Holt is an internationally recognized expert on mitochondrial DNA and diseases caused by defects in the mitochondria. His graduate studies were carried out at the Institute of Neurology, London, where, working with Professors John Morgan-Hughes and Anita Harding, he discovered the first pathological mutations in human mitochondrial DNA, launching the molecular era of Mitochondrial Medicine. After a spell in Professor Giuseppe Attardi´s laboratory at the California Institute of Technology, Los Angeles, he became a junior faculty member at the University of Dundee, Scotland. His research in Dundee led to advances in understanding the behaviour of pathological mitochondrial DNA variants and how they segregate in somatic cells. Work on the replication of mitochondrial DNA, begun in Scotland, became his major focus from 2000-2016 while a Group Leader for the UK´s Medical Research Council. These studies led to the discovery of new mechanisms of mitochondrial DNA replication, the identification of key regulatory cis-elements, such as replication origins, pause sites and termini. In parallel, he identified new mitochondrial DNA interacting proteins, including ATAD3, and later showed that ATAD3 mutations are one of the most frequent causes of mitochondrial disease and that they reconfigure cellular cholesterol metabolism. With Prof. Spinazzola (UCL, UK) he has developed a model in which ATAD3 forms a scaffold that supports and distributes DNA molecules throughout the mitochondrial network. This ‘network within a network’ is reconfigured according to nutrient availability and is heavily dependent on cholesterol, which hitherto was erroneously perceived to be of little importance in mitochondria because of its scarcity.

Awards:

Early in his career IJH received a Lucille Markey Visiting Fellowship to post-doc in the USA, and after returning to the UK he was awarded a Royal Society University Research Fellowship. In 2004 he shared the European Union Descartes Prize (Life Sciences) in recognition of his contributions to mitochondrial research and medicine, and in 2014 was awarded a visiting Professorship in Nijmegen, The Netherlands (Radboud Excellence Programme). In 2017 he moved to the Basque country supported by an Ikerbasque Research Professorship.