Identification and characterization of proteins regulating the metabolic network of cellular fat storage organelles

• Applicant: Dr. Lucia Mastrototaro, since 1/2020
• Subject Area: Biochemistry ; Cell Biology
• Term: from 2017 to 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 389196102

Almost all cells store metabolic energy as fat in specialized organelles, the lipid droplets (LDs). As key players in lipid metabolism, LDs store and provide a plethora of metabolites for a variety of cellular processes and play a major role in metabolic diseases, such as obesity and type 2 diabetes. LDs are integrated into an overall cellular metabolic network, which relies on the functional and physical coupling of LDs and other cellular organelles. Factors required for the efficient coupling and mechanisms regulating them are currently unknown. The aim of this project is to identify and characterize the metabolic network of LDs in its entity. We developed a high-throughput flow cytometry screening-platform to monitor LD dynamics in the model organisms yeast, Saccharomyces cerevisiae. Applying it to a genome-wide screen, we identified candidate proteins which are required for the functional coupling of LDs and other organelles during LD consumption. Here, we aim to analyze the function of the identified proteins at a molecular level. To achieve this, we will apply the following research approaches: 1) Analysis of the molecular function of identified proteins using cell biological, biochemical, and microscopy-based methods. 2) Application of mass spectrometry-based methods to analyze the cellular lipid composition. This will unravel how the identified proteins affect the utilization and distribution of LD-derived lipid metabolites. 3) Analysis of the role of conserved candidate proteins in regulating LD dynamics in mammalian hepatocytes. This translational approach will decipher evolutionary conserved mechanisms underlying the complex metabolic network of LDs. In the light of a global obesity pandemic and an ever increasing prevalence of related diseases, such as type 2 diabetes, we consider this research project essential for the understanding of the underlying cellular mechanisms and the rapid translation of basic research into future prevention- and treatment strategies.

• DFG Programme: Research Grants
• Ehemaliger Antragsteller: Dr. Daniel Markgraf, until 12/2019