Three databases that provide data on transcriptional regulation are described. TRANSFAC is a database on transcription factors and their DNA binding sites. TRRD (Transcription Regulatory Region Database) collects information about complete regulatory regions, their regulation properties and architecture. COMPEL comprises specific information on composite regulatory elements. Here, we describe the present status of these databases and the first steps towards their federation.

DNA sequences that are involved in the control of gene expression in eukaryotes have been collected in conjunction with the proteins binding to and acting through them (TRANSFAC data set). To make these data accessible, the TRANSFAC retrieval program (TRP) has been developed as a database management system which is based upon the network model. This database model possesses particular advantages for data management of a complex structure. The aim of TRP is to provide an easily handled statistical basis for a computational approach to transcription control.

The low-dose combined oral contraceptive containing 3-mg drospirenone/20-microgram ethinyl estradiol administered in a 24/4 regimen significantly reduced acne lesion counts more effectively than placebo and demonstrated greater improvement in the Investigator Static Global Assessment rating of acne. The safety profile was consistent with low-dose combined oral contraceptive use.

Cell suspension and root cultures of Peganum harmala were established expressing a tryptophan decarboxylase cDNA clone from Catharanthus roseus under the control of the cauliflower mosaic virus (CaMV) 35S promoter and terminator sequences. The tryptophan decarboxylase activity of some of the transgenic lines was greatly enhanced (25-40 pkat/mg protein) as compared to control cultures (1-5 pkat per mg protein) and remained high during the growth cycle. While the levels of tryptamine, the product of the reaction catalysed by tryptophan decarboxylase, were unchanged in the transgenic lines, their serotonin contents were enhanced up to 10-fold, reaching levels of 1.5 to 2% dry mass. Thus, tryptamine produced by the engineered reaction was apparently immediately used for enhanced serotonin biosynthesis. The yields of serotonin in transgenic lines overexpressing tryptophan decarboxylase activity were further enhanced to 3-5% dry mass by feeding L-tryptophan, while no or only minor effects were seen when control cultures were fed. These data demonstrate that the production of a plant secondary metabolite can be enhanced greatly via genetic manipulation of the level of activity of the rate-limiting enzyme. The amounts of 13-carboline alkaloids, the other tryptamine-derived metabolites of P. harmala, in contrast, were not affected by the overproduction of tryptamine. The information needed for successfully predicting manipulations that enhance production of a secondary metabolite is discussed.

No abstract