BACKGROUND Pityriasis lichenoides chronica (PLC) and pityriasis lichenoides et varioliformis acuta (PLEVA) are benign T-cell diseases that share several overlapping clinicopathologic features, leading many to believe that they exist as a spectrum rather than as single entities. Previous molecular studies have shown that PLEVA is a clonal lymphoproliferative disorder. To further characterize the...

Defects in the gene encoding Bruton's tyrosine kinase (Btk) result in a disease called X-linked agammaglobulinemia, in which there is a profound decrease of mature B cells due to a block in B cell development. Recent studies have shown that Btk is tyrosine phosphorylated and activated upon B cell antigen receptor (BCR) stimulation. To elucidate the functions of this kinase, we examined BCR sign...

A number of phosphoinositide-specific phospholipases C (PLC) of different species have recently been cloned. The predicted amino acid sequences of these isoforms contain two highly conserved domains. Here we report the identification of a PLC gene of Dictyostelium by using the polymerase chain reaction. Primers were designed coding for highly conserved amino acid regions located within one of t...

The aim of the present study was to investigate transcription dynamics of the a-toxinencoding plc gene relative to two housekeeping genes (gyrA and rplL) in batch cultures of three Clostridium perfringens strains with low, intermediate, and high levels of a-toxin production, respectively. The plc transcript level was always low in the low a-toxin producing strain. For the two other strains, plc...

Defects in the gene encoding Bruton's tyrosine kinase (Btk) result in a disease called X-linked agammaglobulinemia, in which there is a profound decrease of mature B cells due to a block in B cell development. Recent studies have shown that Btk is tyrosine phosphorylated and activated upon B cell antigen receptor (BCR) stimulation. To elucidate the functions of this kinase, we examined BCR sign...

The cytoplasmic regions of the receptors for epidermal growth factor (EGF) and platelet-derived growth factor (PDGF) bind and activate phospholipase C-gamma1 (PLC-gamma1) and other signaling proteins in response to ligand binding outside the cell. Receptor binding by PLC-gamma1 is a function of its SH2 domains and is required for growth factor-induced cell cycle progression into the S phase. Mi...

The perception of pathogen-derived elicitors by plants has been suggested to involve phosphatidylinositol-specific phospholipase-C (PI-PLC) signalling. Here we show that PLC isoforms are required for the hypersensitive response (HR) and disease resistance. We characterised the tomato [Solanum lycopersicum (Sl)] PLC gene family. Six Sl PLC-encoding cDNAs were isolated and their expression in res...

Two genomic clones corresponding to putative pectate lyase genes (plA and plB) were isolated and characterized in strawberry (Fragaria x ananassa cv. Chandler). The corresponding ORFs for the plA and plB genes revealed deduced proteins of 451 and 439 amino acids, respectively, that differ from that of the previously isolated strawberry plC gene. Southern blot analysis has shown that while the p...

BACKGROUND PLC-β signaling is generally thought to be mediated by allosteric activation by G proteins and Ca(2+). Although availability of the phosphatidylinositol-4,5-biphosphate (PIP(2)) substrate is limiting in some cases, its production has not been shown to be independently regulated as a signaling mechanism. WNK1 protein kinase is known to regulate ion homeostasis and cause hypertension w...