The human body consists of hundreds, perhaps thousands of different types of cells, each with different morphologies and functions, despite having the same genome.

Understanding DNA repair mechanisms is essential for advancing plant biotechnology and crop improvement. This study investigates how double-strand breaks (DSBs), induced by CRISPR/Cas systems, are repaired in the model plant Arabidopsis thaliana, and how these processes influence Agrobacterium tumefaciens…

Dit rapport vormt het resultaat van het zogenaamde ALIMENT-project (Animals and Livestock Provisioning in the Modern Town), dat werd gefinancierd door de Vlaamse overheid.

Promotores: T.H.W. Bäck, A. Plaat, Co-promotor: F.J. Verbeek

The objective of this study was to investigate the expression and function of GRHL2 in different breast cancer subtypes.

In this thesis, we used genetically engineered mouse models to identify genes and pathways that are involved in ILC formation and in the development of resistance to FGFR-targeted therapy.

Streptomyces bacteria are a valuable source of natural products, many of which are used in the clinic or in biotechnology.

Nucleoid associated proteins maintain the architecture of the bacterial chromosome and regulate gene expression, hinting that their role as transcription factors may involve local three-dimensional chromosome re-modelling.

Which genes are involved in woodiness and associated traits such as drought tolerance, flowering time, stem elongation, life span, and plant herbivory, and how do these gene regulatory pathways overlap?

This thesis describes the functional analysis of the Arabidopsis AHL15 gene.

Promotor: P.J.J. Hooykaas, Co-Promotores: P.B.F. Ouwerkerk, M. Wang

The bacterial cell wall is a nearly universal structure that offers protection and gives the cell its shape. However, environmental stressors, such as cell wall-targeting antibiotics and hyperosmotic conditions, can induce bacteria to shift to a wall-deficient state. It is unknown whether the lack of…

In this Ph.D. thesis, we characterized two novel upstream regulators of JUB1, HB40, and HB22, in Arabidopsis thaliana. In Chapter 2, we described functions of HB40 in modulating growth and development via the regulation of JUB1 and GA inactivation genes GA2OXs.

Promotor: Prof.dr. G.P. van Wezel

My PhD project studies how the temporally sequential Hox gene expression is regulated during head-tail patterning of the frog embryo.

Plant architecture has distinct forms in different plant species, but also within a species the finalarchitecture of a plant is determined by its gradual development and changes therein induced by environmental conditions during the plant’s life cycle.

The experiments described in this thesis employ local lentiviral knockdowns in brain areas of female zebra finches followed by behavioural assays consisting of preference and Go/Nogo tasks.

Researchers at Leiden University have mapped genes that cause breast cancer cells to migrate. The Leiden toxicologists Professor Bob van de Water, Dr Wies van Roosmalen, Dr Sylvia E. Le Dévédec and colleagues studied 1500 individual genes. They found eight, including the SRPK1 gene, that regulate the…

Regeneration is the ability of an organism to restore damaged or lost tissue with a functional replacement, and without scarring. Many lizards can regenerate their tails.

Harvesting rice from the same field, without planting new rice plants? A discovery may bring this scenario closer. Leiden scientists have discovered a gene that allows annual plants to grow after flowering, instead of dying. Publication on 13 April in Nature Plants.

DNA carries various forms of information. Out of these forms of information the most well-known is classical genetic information.

Salicylic acid (SA) is a plant hormone, which is involved in the defense responses to pathogens and to abiotic stress, and in the regulation of plant growth and development.

Plant-microbe interaction resulted in different physio/chemical responses by host plant and interacting rhizobacteria.

We exploit secondary metabolites of plant to develop pharmaceutical compounds and we genetically modify plant genomes to improve crops.

PhD student Esmee Koedoot studied the underlying processes responsible for metastases in a dangerous type of breast cancer. She hopes to find new possibilities to fight the disease. In December 2019 she obtained her doctorate cum laude.

Leiden biologists have shown that a gene present in plants, animals and yeasts does play an important role in plants, although for years the gene was considered unimportant. It turns out the gene plays a crucial role in the development of vascular tissue in plants. Publication in Nature Plants on 11…

‘It was a discovery we did not expect,’ says Remko Offringa, professor of Plant developmental genetics. Today he publishes a new trait of a versatile gene in Current Biology: it makes the difference in plants between herbaceous and woody stem growth. A useful feature to prevent dehydration.

The way genes are folded determines their activity in our body. Leiden biophysicists are now the first to unravel this structure molecule-by-molecule. Publication on December 1st in Nature’s Scientific Reports.

Master's student Thalia Luden receives an NWO grant for her research proposal about a gene that brings flowering plants back into a growth phase. Companies in floriculture and vegetable seed breeding also contribute to the research.

A publication in Nature Plants by a team of Leiden biologists has received national and international media attention. The researchers can have annuals flower multiple times thanks to a particular gene they discovered.

Drug induced organ toxicity is the main problem of the drug development and drug usage in the clinic. The liver and kidneys are the most sensitive organs towards drug induced toxicity.

In a publication in Science, Noam Zelcer from the Division of Biopharmaceutics describes a previously unrecognized pathway to regulate LDL-cholesterol levels. He is also able to modulate this pathway. This opens the possibility for complementing and improving the efficacy of statins: A class of drugs…

Researchers from the Leiden University Medical Center (LUMC) have successfully used stem cell gene therapy to treat a baby with the severe congenital immune disorder SCID. An important milestone: it is the first time stem cell gene therapy of Dutch origin has been administered to a patient, and also…

Pectin is a plant cell wall polysaccharide made of mainly D-galacturonic acid (GA) subunits. The potency of the filamentous fungus Aspergillus niger to naturally secrete high amounts of pectinases to degrade pectin has been utilized for the industrial production of pectinases.

Climate change is a challenge for both current and future generations. New biological resources have to be developed in order to meet the demand for energy as well as the demand for food.

Soil is a home for an unbelievable diversity and abundance of microbial life that is essential for supporting life on our planet.

To gain more insight into the evolutionary development of orchid flowers and fruits, the orchid species Erycina pusilla was studied. The evolutionary origin of the median petaloid sepal, the callus on the labellum, and the stelidia was studied.

Promotores: Prof.dr. M.K. Richardson, Prof.dr. H.P. Spaink

How do plant defense genes get activated?

In recent decades, climate change has led to more frequent and severe drought events, causing serious consequences such as increased forest mortality and significant crop yield losses. Understanding how drought affects plants, especially economically important herbaceous species, is crucial for predicting…

The molecular mechanisms that instigate a healthy cell to become malignant are fueled by (epi)genetic alterations in so-called driver genes.

The increasing resistance of pathogenic bacteria to antibiotics necessitates the discovery of new medicines.

Increasing the efficiency of gene targeting (GT) as a genome editing tool in plants has been an important goal in plant biotechnology.

Promotors: Prof.dr. P.J. Punt, Prof.dr. C.A.M.J.J. van den Hondel

Promotor: G.P. van Wezel, Co-promotor: Y.H. Choi