The premature ageing disease Hutchinson-Gilford Progeria Syndrome (HGPS)

2 PhD projects offered in the IPP winter call 2020/2021

PHD PROJECT 1: HIGH-THROUGHPUT DISCOVERY OF PATHWAYS THAT DRIVE AGEING

Scientific Background

Ageing is a prime pathological component of most prevalent diseases, including cancer, cardiovascular, neurodegenerative, chronic kidney and lung diseases. At the cellular level, ageing is characterized by several hallmarks, including epigenetic alterations, genomic instability, and loss of protein homeostasis  that lead to an organism-wide functional decline. Unfortunately, our current knowledge of molecular pathways that control cellular ageing, and which modulation can help improve ageing-associated diseases, is severely limited due to lack of robust genetically manipulatable systems to study human aging in a relatively short time span.

The rare human premature aging disease Hutchinson-Gilford Progeria Syndrome (HGPS) is a powerful model to study the underpinning mechanisms of cellular ageing. HGPS is caused by a mutant lamin A protein isoform, progerin. Due to increased accumulation of progerin in the cell nucleus, HGPS patients age about 7 times faster than healthy subjects do, and they invariably die during their teen years from stroke and cardiovascular complications. The cellular and tissue ageing defects of HGPS patients closely resemble those occurring during physiological ageing. This has been attributed to the fact that healthy subjects also accumulate progerin during their lifespan, though at much lower levels than HGPS patients. Understanding the mechanisms through which progerin drives cellular ageing thus can help uncover fundamental biological mechanisms of ageing that hold therapeutic potential for HGPS patients and can be exploited to delay the onset of prevalent ageing-associated diseases.

PhD Project

In order to identify cellular pathways that regulate/influence human ageing we have genetically engineered non-aged wildtype human skin cells, so that we can tightly control the levels and time at which they start expressing progerin. This novel system allows us to induce and investigate cellular ageing in a time span of merely 4 days. Through the use of high-throughput microscopy imaging techniques we can furthermore automatically quantify the degree to which these cells age for a variety of hallmarks. This innovative experimental setup has the major advantage that it allows to functionally test in a high-throughput approach which cellular interventions can prevent ageing from occurring upon induced progerin expression.           

The aim of this PhD project is to identify and elucidate novel molecular mechanisms that drive progerin-induced cellular ageing, and investigate their therapeutic potential in various ageing models. To provide the PhD candidate witha good start in this project, we have recently performed an RNA interference (RNAi) based screen to determine anti-ageing effects for appr. 20.000 genes individually (upon lowering their expression levels). Initial analysis has revealed 300 candidate anti-ageing targets. The PhD candidate will be using a combination of high-throughput microscopy, robotic-automated immunofluorescent staining, RNAi and CRISPR technology, as well as various biochemical assays, to out of these 300 candidates select the therapeutically strongest anti-ageing pathways and elucidate how they molecularly contribute to HGPS and relevant ageing-associated diseases. We are in particular looking for a PhD candidate that has wet-lab experience, is enthusiastic about investigating how phenotypically diverse diseases may have shared pathogenic mechanisms, and is intellectually, technically and socially driven to help make an impact in translational science together with other science-enthusiasts. We are looking forward to hearing from you!

Publications relevant to this project

Kubben N, Misteli T (2017) Shared molecular and cellular mechanisms of premature ageing and ageing‐associated diseases. Nat Rev Mol Cell Biol. 18(10): 595‐609. [link]

Kubben N, Zhang W, Wang L, Voss TC, Yang J, Qu J, Liu GH, Misteli T (2016) Repression of the antioxidant NRF2 pathway in premature aging. Cell. 165(6):1361‐74. [link]

Kubben N, Brimacombe KR, Donegan M, Li Z, Misteli T (2016) A high‐content imaging‐based screening pipeline for the systematic identification of antiprogeroid compounds. Methods. 96: 46‐58. [link]

 

PHD PROJECT 2: DEVELOPING A PROTEOSTATIC THERAPY FOR (PREMATURE) AGEING

Scientific background

Ageing is a biological process that drives the gradual functional deterioration of organisms. About two thirds of human deaths are attributed to chronic ageing-associated diseases, most prominently cardiovascular and neurodegenerative disorders, cancer, diabetes, chronic kidney and lung diseases. Aged cells progressively lose their ability to maintain their proteome functional. This decline of proteostasis (protein homeostasis) is caused by an impairment of proteostasis-regulatory networks, including protein quality control pathways, that promote protein (re)folding and degrade toxic, misfolded protein aggregates. Unfortunately, it is largely unknown which factors initiate and perpetuate the proteostatic collapse during ageing. The identification of weak spots in the proteostatic network that propel ageing would provide exciting new therapeutic opportunities to preserve or enhance proteostatic surveillance until late in life, slow down the effects of ageing, and hence improve healthspan. Major obstacles that have thus far hindered their systematic identification, are the slow and heterogeneous onset and progression of ageing defects and a lack of controllable, genetically manipulatable cell models of human ageing.

The rare human premature ageing disease Hutchinson-Gilford Progeria Syndrome (HGPS) is a powerful model to study the underpinning mechanisms of cellular ageing. HGPS is caused by a mutant lamin A protein isoform, progerin. Due to increased accumulation of progerin in the cell nucleus, HGPS patients age about 7 times faster than healthy subjects do, and they invariably die during their teen years from stroke and cardiovascular complications. There currently is no cure for HGPS. The cellular and tissue ageing defects of HGPS patients closely resemble those occurring during physiological ageing. This has been attributed to the fact that healthy subjects also accumulate progerin during their lifespan, though at much lower levels than HGPS patients. It remains largely unknown why the expression of progerin drives human ageing. Our recent work suggest that the accumulation of toxic progerin protein aggregates triggers cellular ageing and proteostatic collapse due to entrapment of important ageing-regulators, including the proteostatic master-regulator NRF2. A systematic identification of cellular proteins that become entrapped in progerin aggregates, and of molecular pathways that help degrade progerin aggregates, is therefore pivotal in our understanding of proteostatic regulation during ageing, and may provide new therapeutic avenues for the treatment of HGPS patients, and other ageing-associated diseases.

PhD Project

In this research project the PhD candidate will unravel the molecular mechanisms through which mutant progerin impairs major proteostasis regulating networks, and apply this knowledge to develop therapeutic interventions that help strengthen cellular proteostasis, and slow down cellular ageing. Two complementary approaches will be taken by the PhD candidate for this:

Approach 1): You will use a combination of immuno affinity purification, SILAC mass spectrometry, high throughput microscopy and biochemical assays, to identify which ageing regulators are bound and impaired by toxic progerin aggregates. Next, you will determine to which extent these entrapped regulators impair cellular proteostasis, and whether restoration of their activity reverses cellular ageing.

Approach 2): Using a combination of  techniques, including FACS, fluorescent tracing of progerin protein turnover, CRISPR gene-editing, and ‘omics’ techniques we will identify novel proteostatic pathways that aid the cell in degrading toxic progerin protein aggregates and reverse cellular ageing.

Identified therapeutic approaches will further be validated for their anti-ageing effects in an HGPS mouse model. To provide the PhD student with a good start in their project we already have identified one lead therapeutic target for approach 1 (NRF2), for which two activating drugs will be tested in vivo. Also for approach 2 we have already identified one lead target, for which two drugs will be tested in vivo. Positive effects on life- and healthspan in an HGPS mouse model will provide the Progeria Research Foundation with critical data to decide on starting clinical trials to test the efficacy of these anti-ageing interventions in human HGPS patients. 

We are in particular looking for a PhD student that has wet-lab experience, is enthusiastic about becoming skilled in a wide variety of in vitro and in vivo techniques, and is intellectually, technically and socially driven to help make an impact in translational science together with other science-enthusiasts. We are looking forward to hearing from you!

Publications relevant to this project

Kubben N, Misteli T (2017) Shared molecular and cellular mechanisms of premature ageing and ageing‐associated diseases. Nat Rev Mol Cell Biol. 18(10): 595‐609. [link]

Kubben N, Zhang W, Wang L, Voss TC, Yang J, Qu J, Liu GH, Misteli T (2016) Repression of the antioxidant NRF2 pathway in premature aging. Cell. 165(6):1361‐74. [link]

Kubben N, Voncken JW, Demmers J, Calis C, van Almen G, Pinto YM and Misteli T (2010) Identification of differential protein interactors of lamin A and progerin. Nucleus. 1(6):513-25. [link]

 

Contact

 

Nard Kubben

Email

Website: Available per February 1st 2021 on the IMB website