Containment of extended length polymorphisms in silk proteins.

The spider silk gene family to the current date has been developed by gene duplication and homogenization events as well as conservation of crucial sequence parts. These evolutionary processes have created an amazing diversity of silk types each associated with specific properties and functions. In addition, they have led to allelic and gene variants within a species as exemplified by the major ampullate spidroin 1 gene of Nephila clavipes.

Dual reporter systems in yeast and mammalian cells for assessing progesterone receptor modulators.

In the present study we describe the set-up of a new one-hybrid reporter gene assay in Saccharomyces cerevisiae composed of the human progesterone receptor fused to the DNA-binding domain of the yeast transcriptional activator Gal4. This assay allows the convenient estimation of receptor mediated progestogenic as well as antiprogestogenic actions of compounds. The induction of the beta-galactosidase reporter gene expression correlated well with the progesterone receptor affinity and the concentration of the progestins tested.