Center for Molecular Medicine Cologne

Marcus Krüger - C 11

Heart failure in pressure overload hypertrophy: The role of 111000E22RIK in ventricular remodeling and signaling

Introduction

Cardiac remodeling is defined as cellular and interstitial changes that clinically manifest as impairments to heart function. Most drugs used to treat patients with heart failure primarily target neuroendocrine pathways, and only secondarily affect structural remodeling of the failing heart. Thus, improved understanding of metabolic adaption and remodeling of cytoskeletal structures are essential to develop new molecular targets and improve the prognosis of patients with chronic heart failure.

Circulatory system perturbations, such as hypertension, can induce cardiac hypertrophy and lead to irreversible heart failure. To elucidate how signaling and structural proteins contribute to pathological remodeling, we conducted comprehensive quantitative, mass spectrometry-based proteomic and phosphoproteomics analysis to dissect the signaling events that occur after transverse aortic constriction (TAC) in mice. A previously uncharacterized protein was strongly upregulated 2 days after TAC.

We confirmed expression that this candidate is enhanced in patients with cardiac hypertrophy and this unknown protein is mainly expressed in heart and skeletal muscle tissues and localizes to actin fibers. MS-based immunoprecipitation experiments revealed that the protein closely interacts with cytoskeletal, calcium-binding and guanine nucleotide-binding proteins.

However, the function of this protein is completely unknown. This project will examine how cytoskeletal protein expression is upregulated in response to stress and altered metabolic conditions, analyze its interactome during cytoskeletal remodeling, and characterize the consequences of ablating this gene in mice. Furthermore, we will define how this candidate modulates cytoskeletal rearrangements during pressure overload.

Collectively, these experiments will provide new insight into how cytoskeletal proteins contribute to hypertrophy and subsequent heart failure.

Our Aims

  1. We will investigate the protein expression of cytoskeletal proteins in skeletal and heart muscle under different physiological conditions
  2. Generation of genetic gain and loss of function mouse models 
  3. Comprehensive protein-protein interaction studies to expand the network of cytoskeletal proteins and its targets using affinity enrichment and mass spectrometry (AE-MS) and cross-linker MS (XL-MS)
  4. Investigate the role of reversible phosphorylations of cytoskeletal proteins after β-adrenergic stimulation in heart tissue 

Previous Work

My group focuses on the analysis of differentially expressed proteins derived from biological specimens, including cell lines and mouse tissues.

The aim is to study heart and skeletal disease models in mice with relevance to human disorders and syndromes. In particular, we investigate insulin-dependent phosphorylation profiles in insulin sensitive cells, including adipocytes and skeletal muscle cells and are interested in the interplay between protein phosphorylation and protein ubiquitination patterns after insulin stimulation.

Over the past years, mass spectrometry-based proteomics has become a powerful tool. My group will use state-of-the-art high resolution mass spectrometry in combination with liquid chromatography (LC-MS/MS) and ESI (electrospray ionization) to analyze complex biological samples in depth. For protein and posttranslational modification (PTM) quantification we will use the SILAC technology (stable isotope labeling of amino acids in cell culture).

We have recently extended this method to completely label mice and zebrafish with a diet containing the 13C6-substituted version of lysine. This method allows us to analyze cells and tissues in living animals which are not accessible for cell culture systems.  Identified targets will be further evaluated by several molecular biology methods including the generation of knockout mice. 

Prof. Dr. Marcus Krüger CMMC Cologne
Prof. Dr. Marcus Krüger

Institute for Genetics / RG location - CECAD Building | CECAD / CMMC Proteomics Facility

Principal Investigator - C 11

Head - CECAD / CMMC Proteomics Facility

+49 221 478 84140

+49 221 478 4833

Institute for Genetics / RG location - CECAD Building | CECAD / CMMC Proteomics Facility

Joseph-Stelzmann-Str. 26

50931 Cologne

http://cecad.uni-koeln.de/Prof-Dr-Marcus-Krueger.362.0.html

CMMC Profile Page

Curriculum Vitae (CV)

Publications - Marcus Krüger

Link to PubMed