Endocrine Abstracts

GnRH is secreted in pulses and its effects on pituitary gonadotropes depend on pulse frequency. This is crucial for physiological control and therapeutic manipulation of the system (in IVF and treatment of hormone-dependent cancers) but GnRH pulse frequency decoding mechanisms are unknown. The simplest form of frequency dependence is a linear relationship between integrated inputs and outputs but such ‘integrative tracking’ cannot explain the bell-shaped frequency-re...

GnRH acts via G-protein coupled receptors to stimulate phospholipase C. This activates protein kinases C, driving the activation of extracellular signal regulated kinases (ERKs) that mediates transcriptional effects of GnRH. GnRH is secreted in pulses that cause rapid, transient and reproducible ERK activation (1). ERK response kinetics dictate biological consequences in many systems and, although GnRH-mediated ERK activation has been thoroughly explored, little is known about...

GnRH acts via G-protein coupled receptors to stimulate synthesis and secretion of luteinizing hormone and follicle-stimulating hormone. GnRH activates phospholipase C, causing calcium mobilisation and influx, activation of protein kinase C and stimulation of mitogen-activated protein kinase cascades. GnRH is secreted in brief pulses with each pulse causing rapid and transient activation of extracellular signal regulated kinases (ERKs) (1), yet very little is known about what s...

Single cell measurements of signalling proteins typically reveal high cell–cell variability raising questions about how reliably individual cells sense their environment in order to make decisions. Information theoretic approaches can be used to explore such sensing, treating cell signalling pathways as ‘noisy’ communication channels. Mutual information (MI) can be calculated between system inputs and outputs as a statistical measure of the reliability of sensin...

One way in which cells receive information about their environment is through hormones binding to appropriate receptors on their cell surface. Single cell measurements of signalling proteins typically reveal high cell–cell variability raising questions about how reliably individual cells sense their environment in order to make decisions. Information theoretic approaches can be used to explore such sensing, treating cell signalling pathways as ‘noisy’ communicat...

GnRH acts via Gq/11-coupled GPCRs on gonadotropes to control synthesis and secretion of LH and FSH. We use mathematical and statistical approaches as well as automated cell imaging to explore this system. In cells expressing ERK2–GFP and GnRH receptors, GnRH pulses cause rapid and transient nuclear translocation of ERK2–GFP, providing a live-cell readout for ERK activation1. A mathematical model trained against this data predicted greater sensitivity to re...

Gonadotrophs in rats, mice and humans, express an intact natriuretic peptide system, in which C-type natriuretic peptide (CNP) is the predominant member. Despite showing an interaction between CNP and GnRH at the level of cGMP and Ca2+ signalling, the role of CNP in gonadotroph biology is poorly understood. In this study, we utilise a novel multiplex qRT-PCR assay, examining simultaneous expression of natriuretic peptide genes along with genes for gonadotroph transc...