Endocrine Abstracts

Kyphosis is a common spinal disorder affecting up to 8.3% of the population, and associated with significant morbidity. Familial and twin studies have implicated a genetic involvement. However, the causative genes have not been identified. Studies investigating the underlying molecular mechanisms are hampered by genetic heterogeneity, small families and variable modes of inheritance displayed by different kindreds. To overcome these limitations, we investigated 12 week old pro...

Osteoarthritis (OA) may be associated with endocrine disorders such as hypothyroidism, obesity, primary hyperparathyroidism or acromegaly, although often its cause remains undefined. To facilitate investigations of the underlying molecular mechanisms of OA we have investigated N-ethyl-N-nitrosourea (ENU) mutant mice using a genotype-driven approach in which candidate genes are examined for mutations. One such investigated gene is growth and differentiation factor...

The tumour suppressor menin, encoded by the multiple endocrine neoplasia type 1 (MEN1) gene, has been reported to be a component of the Wnt/β-catenin signalling pathway. To investigate the effects of menin loss on this pathway, we have determined the cDNA expression profiles of pituitary tumours from 5 Men1+/− mice and in normal pituitaries from 5 Men1+/+ littermates by extracting total RNA and by hybridizing it to Affymetrix Mous...

The multiple endocrine neoplasia type 1 (MEN1) gene, which when mutated gives rise to parathyroid, pancreatic and pituitary tumours, has been shown to have a role in embryogenesis, as Men1-null mice (Men1−/−) are embryonic lethal by 12.5 days post coitum (dpc). MicroRNAs (miRNAs) are emerging as potent regulators of early mammalian embryogenesis, and we therefore undertook expression profiling of miRNAs in Men1+/+ and M...

GATA3 mutations cause the congenital autosomal dominant hypoparathyroidism, Deafness and Renal dysplasia (HDR) syndrome. GATA3 belongs to a family of dual zinc-finger transcription factors that recognise the consensus (A/T)GATA(A/G) motif and are involved in vertebrate embryonic development. We investigated a HDR proband for GATA3 abnormalities. Venous blood was obtained after informed consent, as approved by the local ethical committee, and leukocyte DNA extracted. GATA3 spec...

The calcium sensing receptor (CaSR) is a G protein coupled receptor that is expressed in type A intercalated cells of the distal convoluted tubule and cortical collecting ducts, where it is involved in renal proton excretion. We have therefore investigated the Nuf mouse, which has an activating CaSR mutation (Leu723Gln) that leads to hypocalcaemia, hypercalciuria, renal calcification, a urinary concentrating defect, and cataracts, for disturbances in acid-base homeostasis. Mic...

The calcium-sensing receptor (CaSR) is a G protein coupled receptor that is expressed widely, including pancreatic beta cells where it has been shown to modulate insulin secretion in vitro. However, the role of the CaSR in regulating in vivo insulin secretion and glucose homeostasis remains unknown. We have therefore investigated the Nuf mouse, which has an activating CaSR mutation (Leu723Gln), to determine whether abnormal CaSR function in vivo affects gl...

Familial juvenile hyperuricaemic nephropathy (FJHN), an autosomal dominant disorder characterised by raised serum urate, reduced fractional excretion of uric acid (FEUA), a urine concentrating defect, and progressive renal failure, is caused by mutations in the UMOD gene, encoding uromodulin (Tamm–Horsfall glycoprotein). The FJHN-causing UMOD mutations are missense mutations (>90%) or inframe deletions (<10%), and none result in prematurely truncated...

Mutations of the transcription factor GATA3, which is important for maintaining human breast luminal epithelial cell differentiation and quiescence, have been reported in 17 oestrogen receptor (ER) positive breast cancers, although the functional effects of these mutations have not been studied. We therefore investigated 56 ER-positive breast cancers for GATA3 mutations. The tumours were macrodissected, and immunohistochemistry for GATA3 revealed a strong correlation between E...

Glial cells missing B (GCMB), which is the mammalian homologue of the Drosophila GCM gene, encodes a 506 amino acid parathyroid-specific transcription factor that contains: a DNA-binding domain (residues 21–174); a predicted nuclear localization signal (residues 176–193); an inhibitory domain (residues 258–347); and two transactivation domains (residues 174–263, and residues 428–506). To date only two different GCMB m...