Endocrine Abstracts

Neonates harbouring germline gain-of-function TSHR mutations (M453T, L629F) have been reported with transient proptosis. This resolves once euthyroidism is achieved. In contrast children expressing TSHR mutations (V597L, I486T) fail to thrive, with weight gain and height between the 0.4th and 2nd centiles. We have previously demonstrated TSHR expression in preadipocytes undergoing adipogenesis. We now investigate the consequences of constitutively active TSHR mutation expressi...

11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1) has been implicated in the pathogenesis of human obesity and insulin resistance through 11-oxoreductase activation of cortisol (F) from cortisone (E) stimulating adipocyte differentiation and hepatic glucose output. In its purified state however, 11beta-HSD1 is a dehydrogenase inactivating F to E. In patients with cortisone reductase deficiency we recently identified two inactivating mutations, delta29bp and R453Q, withi...

Parathyroid hormone-related peptide (PTHrP)have been found to be expressed in a variety of human tumors including colon and it was originally identified as the causative agent of humoral hypercalcemia of malignancy (HHM), We used a human colonic cell line (LOVO) as a model to study the mechanism for the proliferative effects of PTHrP. The PTHrP constructs expressing PTHrP in sense or antisense orientation were constructed by cloning hPTHrP complementary DNA (cDNA) coding for a...

3beta-hydroxysteroid dehydrogenase (3beta-HSD) expression is essential for the synthesis of all classes of steroid hormones, converting delta5beta-hydroxysteroids into hormonally active delta4-3-ketosteroids in NAD+-dependent reactions. Numerous 3beta-HSD isoforms have been described in mouse, rat, human and other mammals, all with distinct tissue and developmentally specific expression, distinct kinetics, with alternative substrate specificity...

The delivery of genes encoding neurotrophic growth factors (NFG) to injured CNS neurons promotes survival and sustains axon regeneration. The plasmid-based non-viral vectors that we have used are less toxic and safer than viruses. However, their efficiency is low, particularly in non-proliferating cells like neurons, where penetration of the nuclear membrane to access transcriptional machinery is a major factor limiting activity. We are, therefore, exploiting cytoplasmic expre...

In humans only thyroid hormone (T3) receptor (TR) beta1 and beta2 mRNAs have been identified, whereas alternative splicing generates recently characterised beta3 and deltabeta3 transcripts in rat and further N-terminal isoforms in other species. We investigated whether additional transcripts arise from the human TRbeta gene by 5'-RACE. Five distinct TRbeta1 transcripts were isolated, including the previously described TRbeta1 mRNA and four novel 5'-untranslated region (5'-UTR)...

Introduction: Identifying leptin agonists and antagonists requires a reliable bioassay responsive to physiological levels of leptin. The leptin receptor exists in multiple isoforms but Ob-Rb, the full length receptor, mediates the biological actions of leptin and its predominant signalling pathway is through STAT3. We report the development of a bioassay based on a STAT3 firefly luciferase reporter. Materials and Methods: HEK 293 cells were transfected with varying amounts of ...

Oestrogens act via oestrogen receptors (ER) that are expressed in a wide range of tissues including the vasculature, bone and gonads. Two ER genes known as ERalpha and ERbeta have been identified. In the human splice variants of ERbeta have been identified. ERs form both homodimers and heterodimers upon ligand binding. The aim of the present experiments was to study the functional activity of ERbeta1 (wild type) and ERbeta variant (ERbeta2) in single and double transfection as...

Regulation of many pituitary-specific genes involves calcium signalling, yet the mechanisms and signalling molecules involved have yet to be established. CaMK's are expressed in a wide variety of tissues, and are known to modulate transcriptional regulators such as MAPK's and CREB. It is unclear as to which anterior pituitary cell types express CaMK's, or which isoforms are present. We have examined the presence and localisation of type II and IV CaMK's in alphaT3-1, LbetaT2 (...

Introduction. We have previously used a synthetic phage display library to derive single chain (ScAbs) antibodies which bind GnSAF bioactivity in-vitro. However, recovery of GnSAF using the ScAbs, which tended to aggregate and become unstable, was limited. We have therefore engineered these ScAbs into full-length human IgG forms.Methods. CDR regions from soluble expression plasmids for two different GnSAF-recognising ScAbs were amplified by PCR. Two uni...