ERC FUNDED PROJECTS

In physiological situations, the extracellular matrix (ECM) sequesters cytokines, localizes them, and modulates their signaling. Thus, physiological signaling from cytokines occurs primarily when the cytokines are interacting with the ECM. In therapeutic use of cytokines, however, this interaction and balance have not been respected; rather the growth factors are merely injected or applied as soluble molecules, perhaps in controlled release forms. This has led to modest efficacy and substantial concerns on safety. Here, we will develop a protein engineering design for second-generation cytokines to lead to their super-affinity binding to ECM molecules in the targeted tissues; this would allow application to a tissue site to yield a tight association with ECM molecules there, turning the tissue itself into a reservoir for cytokine sequestration and presentation. To accomplish this, we have undertaken preliminary work screening a library of cytokines for extraordinarily high affinity binding to a library of ECM molecules. We have thereby identified a small peptide domain within placental growth factor-2 (PlGF-2), namely PlGF-2123-144, that displays super-affinity for a number of ECM proteins. Also in preliminary work, we have demonstrated that recombinant fusion of this domain to low-affinity binding cytokines, namely VEGF-A, PDGF-BB and BMP-2, confers super-affinity binding to ECM molecules and accentuates their functionality in vivo in regenerative medicine models. In the proposed project, based on this preliminary data, we will push forward this protein engineering design, pursuing super-affinity variants of VEGF-A and PDGF-BB in chronic wounds, TGF-beta3 and CXCL11 in skin scar reduction, FGF-18 in osteoarthritic cartilage repair and CXCL12 in stem cell recruitment to ischemic cardiac muscle. Thus, we seek to demonstrate a fundamentally new concept and platform for second-generation growth factor protein engineering.

2 368 170 €

Start date: 2014-05-01, End date: 2019-04-30

"Regulation and fidelity of gene expression is fundamental to the differentiation and maintenance of all living organisms. While historically attention has been focused on the process of transcriptional activation, we predict that RNA turnover pathways are equally important for gene expression regulation. This has been implied for selected protein-coding RNAs (mRNAs) but is virtually unexplored for non-protein-coding RNAs (ncRNAs). The intention of the EURECA proposal is to establish cutting-edge research to characterize mammalian nuclear RNA turnover; its factor utility, substrate specificity and regulatory capacity. We foresee that RNA turnover is at the core of gene expression regulation - forming intricate connection to RNA productive systems – thus, being centrally placed to determine RNA fate. EURECA seeks to dramatically improve our understanding of cellular decision processes impacting RNA levels and to establish models for how regulated RNA turnover helps control key biological processes. The realization that the number of ncRNA producing genes was previously grossly underestimated foretells that ncRNA regulation will impact on most aspects of cell biology. Consistently, aberrant ncRNA levels correlate with human disease phenotypes and RNA turnover complexes are linked to disease biology. Still, solid models for how ncRNA turnover regulate biological processes in higher eukaryotes are not available. Moreover, which ncRNAs retain function and which are merely transcriptional by-products remain a major challenge to sort out. The circumstances and kinetics of ncRNA turnover are therefore important to delineate as these will ultimately relate to the likelihood of molecular function. A fundamental challenge here is to also discern which protein complements of non-coding ribonucleoprotein particles (ncRNPs) are (in)compatible with function. Balancing single transcript/factor analysis with high-throughput methodology, EURECA will address these questions."

2 497 960 €

Start date: 2014-04-01, End date: 2019-03-31

The ribotoxic stress response (RSR) surveys the structural and functional integrity of ribosomes and is triggered by diverse groups of ribotoxins (e.g. ricin), UV irradiation and some chemotherapeutics. When presented with impaired ribosomes, the proximal MAPKKK ZAK activates MAP kinases p38 and JNK to initiate a powerful inflammatory response. This signalling contributes to the detrimental reactions to ribotoxins and fatal side effects of cancer therapy. However, despite decades of research into the RSR, the physiological relevance of the underlying pathway in whole organisms is unknown. I hypothesize that the RSR constitutes a general translation quality control pathway and hence I aim to uncover the physiological and pathological implications of RSR impairment in mice and nematodes. In one line of investigation, I will elucidate the connections between UV radiation and RSR-mediated p38 activation. I hypothesize that this signalling pathway is critical for sunlight-induced skin inflammation and development of skin cancers of different cellular origins. Rewardingly, we found that cells from our ZAK knockout (KO) mice are refractory to UV-induced p38 activation, which is a significant contributor to skin cancer development. My team has also observed deregulation of protein translation in RSR-deficient human and mouse cells, and a reduced lifespan of ZAK KO nematodes. Thus encouraged, I will determine the impact of the RSR pathway on cancer development and aging processes in mice, and I will unravel the molecular connections between defective ribosomes, RSR activation and regulation of translation. Finally, I am in a unique position to evaluate the RSR as a putative drug target and I will investigate the potential of ZAK inhibition to treat or prevent skin cancer, and to remedy inflammation arising from infection with ribotoxin-producing bacteria. In sum, PHYRIST will yield the first detailed insight into the in vivo relevance of the ribotoxic stress response.

1 997 678 €

Start date: 2020-06-01, End date: 2025-05-31