Eukaryotic cells invoke mechanisms to promote survival when confronted with cellular stress or damage to the genome. The protein kinase Chk1 is an integral and conserved component of the DNA damage response pathway. Mutation or inhibition of Chk1 results in mitotic death when cells are exposed to DNA damage. Oxidative stress activates a pathway that results in nuclear accumulation of the bZIP t...

Transcription termination by RNA polymerase II is coupled to transcript 3' end formation. A large cleavage and polyadenylation complex containing the major poly(A) polymerase Pap1 produces mRNA 3' ends, whereas those of nonpolyadenylated snoRNAs in yeast are formed either by endonucleolytic cleavage or by termination, followed by trimming by the nuclear exosome. We show that synthesis of indepe...

Activation of the transcription factor NF-kappaB/Rel has been shown to be involved in inflammatory disease. Here we studied the role of RelA/p65, the main transactivating subunit, during acute pancreatitis using a Cre-loxP strategy. Selective truncation of the rela gene in pancreatic exocrine cells led to both severe injury of the acinar cells and systemic complications including lung and liver...

Sugar-induced anthocyanin accumulation has been observed in many plant species. We observed that sucrose (Suc) is the most effective inducer of anthocyanin biosynthesis in Arabidopsis (Arabidopsis thaliana) seedlings. Other sugars and osmotic controls are either less effective or ineffective. Analysis of Suc-induced anthocyanin accumulation in 43 Arabidopsis accessions shows that considerable n...

The benzylisoquinoline alkaloid papaverine, synthesized in low amount in most of the opium poppy varieties of Papaver somniferum, is used as a vasodilator muscle relaxant and antispasmodic. Papaverine biosynthesis remains controversial as two different routes utilizing either (S)-coclaurine or (S)-reticuline have been proposed with uncharacterized intermediate steps. In an attempt to elucidate ...

Inducible gene expression is a powerful tool to study and engineer genes whose overexpression could be detrimental for the host organisms. However, only limited systems have been adopted in plant biotechnology. We have developed an osmotically inducible system using three components of plant origin, RD29a (Responsive to Dehydration 29A) promoter, CBF3 (C-repeat Binding Factor 3) transcription f...

1 The content of flavonoids increases in response to nitrogen and phosphorus depletion in 2 plants. Manipulation of these macronutrients may therefore be used to control the levels 3 of desirable compounds and improve plant quality. Key enzymes in the shikimate 4 pathway, which feeds precursors into the flavonoid pathway, are regulated post5 translationally by feedback from aromatic amino acids...

We have identified an essential gene, called FIP1, encoding a 327 amino acid protein interacting with yeast poly(A) polymerase (PAP1) in the two-hybrid assay. Recombinant FIP1 protein forms a 1:1 complex with PAP1 in vitro. At 37 degrees C, a thermosensitive allele of FIP1 shows a shortening of poly(A) tails and a decrease in the steady-state level of actin transcripts. When assayed for 3'-end ...

Methylglyoxal, a toxic metabolite synthesized in vivo during glycolysis, inhibits cell growth. One of the mechanisms protecting eukaryotic cells against its toxicity is the glyoxalase system, composed of glyoxalase I and II (glo1 and glo2), which converts methylglyoxal into d-lactic acid in the presence of glutathione. Here we have shown that the two principal oxidative stress response pathways...

Lipins are the founding members of a novel family of Mg(2+)-dependent phosphatidate phosphatases (PAP1 enzymes) that play key roles in fat metabolism and lipid biosynthesis. Despite their importance, there is still little information on how their activity is regulated. Here we demonstrate that the functions of lipin 1 and 2 are evolutionarily conserved from unicellular eukaryotes to mammals. Th...