The SlFRK4 promoter is active only during late stages of pollen and anther development.

Carbohydrates are essential for male gametophyte development. However, our understanding of the mechanism by which the sugar supply is controlled in the stamen is still in its infancy. We previously reported on the stamen-specific expression of the tomato (Solanum lycopersicum) sugar metabolic gene, fructokinase 4 (SlFRK4).

From dusk till dawn: one-plasmid systems for light-regulated gene expression.

Signaling photoreceptors mediate diverse organismal adaptations in response to light. As light-gated protein switches, signaling photoreceptors provide the basis for optogenetics, a term that refers to the control of organismal physiology and behavior by light. We establish as novel optogenetic tools the plasmids pDusk and pDawn, which employ blue-light photoreceptors to confer light-repressed or light-induced gene expression in Escherichia coli with up to 460-fold induction upon illumination.

ppGpp analogues inhibit synthetase activity of Rel proteins from Gram-negative and Gram-positive bacteria.

A prominent feature of the stringent response is the accumulation of two unusual phosphorylated derivatives of GTP and GDP (pppGpp: 5'-triphosphate-3'-diphosphate, and ppGpp: 5'-3'-bis-diphosphate), collectively called (p)ppGpp, within a few seconds after the onset of amino-acid starvation. The synthesis of these 'alarmone' compounds is catalyzed by RelA homologues. Other features of the stringent response include inhibition of stable RNA synthesis and modulation of transcription, replication, and translation.

ppGpp analogues as antibacterial compounds.

Immediately after sensing the inception of amino acid starvation, bacteria respond pleiotropically with the stringent response via RelA, mainly resulting in the accumulation of the signal molecule (p)ppGpp. A series of analogues of ppGpp that inhibit RelA activity was prepared in order to control the ability of bacteria cells to react to the changes in their environment. Some of those compounds presented very clear inhibitory effect on both Gram positive and negative bacteria in vitro.

It depends on the hinge: a structure-functional analysis of galectin-8, a tandem-repeat type lectin.

Galectin-8, a member of the galectin family of mammalian lectins, is made of two carbohydrate-recognition domains (CRDs), joined by a "hinge" region. Ligation of integrins by galectin-8 induces a distinct cytoskeletal organization, associated with activation of the extracellular-regulated kinase (ERK) and phosphatidylinositol 3-kinase signaling cascades. We show that these properties of galectin-8 are mediated by the concerted action of its two CRDs and involve both protein-sugar and protein-protein interactions.