Paula I. van Noort

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Identification of RF-amide-related peptides (RFRP), as putative mammalian orthologs of the avian gonadotropin-inhibitory hormone, has drawn considerable interest on its potential effects and mechanisms of action in the control of gonadotropin secretion in higher vertebrates. Yet, these analyses have so far relied mostly on indirect approaches, while direct(More)
RF-amide related peptides (RFRP), as putative mammalian orthologs of the avian gonadotropin-inhibitory hormone (GnIH), have been proposed as key regulators of gonadotropin secretion in higher vertebrates. Yet considerable debate has arisen recently on their physiological relevance and potential mechanisms and sites of action. Present studies were undertaken(More)
Quercetin 2,3-dioxygenase (2,3QD) is a copper-containing dioxygenase that catalyses the oxidation of the flavonol quercetin to 2-protocatechuoylphloroglucinol carboxylic acid with concomitant production of carbon monoxide. In contrast to iron dioxygenases, very little is known about copper dioxygenases. We have characterized 2,3QD from the fungus(More)
Quercetin 2,3-dioxygenase is a copper-containing enzyme that catalyzes the insertion of molecular oxygen into polyphenolic flavonols. Dioxygenation catalyzed by iron-containing enzymes has been studied extensively, but dioxygenases employing other metal cofactors are poorly understood. We determined the crystal structure of quercetin 2,3-dioxygenase at 1.6(More)
Ovulation is triggered by the preovulatory rise of gonadotropins, which is in turn elicited by the preceding increase in circulating estrogen. Kisspeptins, ligands of G protein-coupled receptor 54 encoded by the KiSS-1 gene, have emerged as potent stimulators of GnRH/LH secretion, and KiSS-1 neurons at the anteroventral periventricular nucleus have been(More)
Kisspeptins (Kp), products of the Kiss1 gene that act via Gpr54 to potently stimulate GnRH secretion, operate as mediators of other regulatory signals of the gonadotropic axis. Mouse models of Gpr54 and/or Kiss1 inactivation have been used to address the contribution of Kp in the central control of gonadotropin secretion; yet, phenotypic and hormonal(More)
Ovulation is triggered by the preovulatory surge of gonadotropins that, in rodents, is defined by the concomitant rise in circulating LH and FSH at the afternoon of proestrus (primary surge), followed by persistently elevated FSH levels at early estrus (secondary surge). In recent years, kisspeptins, products of the KiSS-1 gene that act via G(More)
Nuclear receptors (NRs) are ligand-dependent transcription factors that play a central role in various physiological processes. The pharmaceutical industry has great interest in this gene-family for the discovery of novel or improved drugs for treatment of, for example, cancer, infertility, or diabetes. The usage of three-dimensional coordinates of protein(More)
Reversing epithelial-to-mesenchymal transition (EMT) in cancer cells has been widely considered as an approach to combat cancer progression and therapeutic resistance, but a limited number of broadly comprehensive investigations of miRNAs involved in this process have been conducted. In this study, we screened a library of 1120 miRNA for their ability to(More)
Malignant melanoma is an aggressive form of skin cancer with poor prognosis. Despite improvements in awareness and prevention of this disease, its incidence is rapidly increasing. MicroRNAs (miRNAs) are a class of small RNA molecules that regulate cellular processes by repressing messenger RNAs (mRNAs) with partially complementary target sites. Several(More)