Dynamic interactions of proteins of the inner nuclear membrane and the nuclear pore complex

• Applicant: Professor Dr. Ralph Kehlenbach
• Subject Area: Cell Biology
• Term: since 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 556208802

The nucleus is surrounded by the inner and the outer nuclear membranes (INM, ONM), which are connected at the level of the nuclear pores complexes (NPCs), the gates for transport of macromolecules between the nucleus and the cytoplasm. In this project, we plan to investigate Tmem209, a membrane protein that localizes to the endoplasmic reticulum and the INM and that interacts with proteins of the NPC (nucleoporins). So far, only three nucleoporins containing a transmembrane domain (TMD) have been described. We will now test our major working hypothesis that Tmem209 is a novel, bona fide TMD-nucleoporin itself. Overexpression of Tmem209 specifically affected individual nucleoporin(s), whereas its depletion affected cell cycle progression. We will investigate the relation of Tmem209 to nucleoporins and proteins of the INM in detail and also analyze its role in mitosis and, possibly, in NPC-biogenesis. Furthermore, we will address a possible function of Tmem209 during muscle cell differentiation using the C2C12 cell system.

• DFG Programme: Research Grants