Líffræðifélag Íslands - biologia.is
Líffræðiráðstefnan 2021

Erindi/veggspjald / Talk/poster E47

Genomically recoded E.coli enable single-molecule spectroscopy of MITF

Höfundar / Authors: Matthías Már Valdimarsson, Kjartan Skarphéðinsson, Eiríkur Steingrímsson(co-PI), Pétur Orri Heiðarsson(co-PI)

Starfsvettvangur / Affiliations: Háskóli Íslands og Raunvísindastofnun Háskólans

Kynnir / Presenter: Matthías Már Valdimarsson

The proteomes of mammalian cells are a paradigm of incredible diversity and adaptability. From roughly 20 000 genes, hundreds of thousands of different proteins are translated that are then decorated from N- to C-termini in post-translational modifications that are vital to their adaptable function. Phosphorylation is the most common of these modifications, with most of the human proteome phosphorylated at any given time. Phosphorylation allows for a rapid response to changing stimuli and thus proteins involved in signalling, such as transcription factors, are especially common targets of phosphorylation. The melanocyte master regulatory factor MITF is a known oncoprotein in melanoma that is highly phosphorylated, with most sites being of unknown function. The intrinsically disordered nature of the phosphorylated domains and heterogenous phosphorylation in mammalian cells prevent many traditional in vitro methods from being applied to it. To resolve these issues and understand the role of phosphorylation for the function of MITF we implemented an orthogonal translation system in genomically recoded E.coli to produce phosphorylated MITF for single-molecule fluorescence spectroscopy and NMR experiments. These experiments will map the structure and dynamics of MITF and how they are modulated by phosphorylation. An understanding of the impact of phosphorylation on the dynamics and structure of MITF is a prerequisite for correlating the molecular mechanisms of MITF with its adaptability and central role in melanoma biology.