Endocrine Abstracts

Alternative promoters control many genes including prolactin (PRL), which in man is expressed at extra-pituitary sites controlled by an alternative promoter located 5.8 Kbp upstream of the pituitary transcription start site. Previous studies using short promoter fragments may be misleading, as the human hPRL genomic locus has many conserved far-upstream regions. To study the function of the alternative promoter, we engineered a bacterial artificial chromosome (BAC) expressing ...

Pituitary development, in particular the differentiation of anterior pituitary endocrine cells, remains to be fully understood, and may have implications for adult pituitary plasticity and hyperplasia. We have used prolactin-reporter transgenic rats to characterise prolactin transcription during the appearance of newly formed lactotroph cells during fetal development.Transgenic rats with the firefly luciferase reporter gene inserted into exon 1b of a 160...

Prolactin (PRL) is a hormone mainly produced by the lactotroph cells of the anterior pituitary gland. Besides its pivotal role in reproduction, PRL has also been found to have immuno-modulatory properties. The pituitary is the main source of circulating PRL, however it is also expressed in humans at extra-pituitary sites1. In extra-pituitary tissues, PRL mRNA contains an extra exon (exon 1a), and expression is regulated by an alternative promoter upstream of the pit...

Mammalian genes display pulsatile transcription dynamics with bursts of expression occurring with variable duration and frequency. Using the human prolactin gene as a model of tissue specific gene regulation, we have characterised the transcription dynamics of this gene in cell lines, primary cells and pituitary tissue slices. Our data indicate that the tissue environment may have an important influence on cellular transcription activity. Cultures of cells from enzymatically d...