Seipin of Phaeodactylum tricornutum: LINKING LIPID DROPLET BIOSYNTHESIS AND DEGRADATION

Protein structure is closely linked to function. In human, yeast, and fly, the luminal domain
structure of Seipin oligomers has been resolved by Cryo-EM, revealing remarkably conserved
features. This prompted the prediction of the PtSeipin structure using AlphaFold. Superimposition
of the predicted PtSeipin luminal domain onto the human Seipin structure highlighted unique
regions absent in other homologs, notably two loops specific to diatoms and eustigmatophytes.
During my first PhD year, I attempted PtSeipin expression for structural characterization in several
heterologous systems, including cell-free, bacterial, and yeast platforms.
A different approach was then tested by transiently expressing PtSeipin in Nicotiana benthamiana
leaves. The determination of the PtSeipin structure could provide insights into its functional
domains and support advanced analyses, including Molecular Dynamics Simulations.