Lymphocyte function-associated antigen 3 (LFA-3)' is a widely distributed cell surface glycoprotein that is a ligand for the T lymphocyte CD2 glycoprotein (1-4). This receptor-ligand pair is used in many intercellular adhesion interactions, including binding ofcytolytic Tlymphocytes to target cells (3) and thymocytes to thymic epithelial cells (4). Both CD2 and one form ofLFA-3 have membrane-sp...

Plant growth is severely affected by toxic concentrations of heavy metals. On characterizing the heavy metal-induced signalling pathways, the effects of cadmium (CdCl2) and copper (CuCl2) on MBP (myelin basic protein) kinase activities in Oryza sativa L. cv. TNG67 were analysed and it was found that Cd2+-induced 42 kDa MBP kinase has the characteristics of a mitogen-activated protein (MAP) kina...

Plant accumulation of Fe and other metals can be enhanced under Fe deficiency. We investigated the influence of Fe status on heavy-metal and divalent-cation uptake in roots of pea (Pisum sativum L. cv Sparkle) seedlings using Cd2+ uptake as a model system. Radiotracer techniques were used to quantify unidirectional 109Cd influx into roots of Fe-deficient and Fe-sufficient pea seedlings. The con...

Manganese peroxidase (MnP) is the one of the important ligninolytic enzymes produced by lignin-degrading fungi which has the great application value in the field of environmental biotechnology. Searching for new MnP with stronger tolerance to metal ions and organic solvents is important for the maximization of potential of MnP in the biodegradation of recalcitrant xenobiotics. In this study, it...

Cadmium block of calcium channels was studied in chicken dorsal root ganglion cells by a whole-cell patch clamp that provides high time resolution. Barium ion was the current carrier, and the channel type studied had a high threshold of activation and fast deactivation (type FD). Block of these channels by 20 microM external Cd2+ is voltage dependent. Cd2+ ions can be cleared from blocked chann...

We examined the role of the T-cell antigen CD2 in the regulation of erythropoiesis by the lymphokine cascade. T-cell interleukin-2 (IL-2) receptors (p55) were induced via triggering of the antigen receptor-associated CD3 epitope. Before CD3 triggering T cells were preincubated with a CD2-blocking (Leu-5b) or isotype control antibody. T-cell pellets were employed during incubation to facilitate ...

Perturbation of the catalytic inorganic core (Mn4Ca1OxCly) of the photosystem II-water-oxidizing complex (PSII-WOC) isolated from spinach is examined by substitution of Ca2+ with cadmium(II) during core assembly. Cd2+ inhibits the yield of reconstitution of O2-evolution activity, called photoactivation, starting from the free inorganic cofactors and the cofactor-depleted apo-WOC-PSII complex. C...

We have analyzed the transmembrane signaling operating in human cytolytic lymphocytes lacking surface expression of the CD3/TCR complex. Peripheral blood lymphocytes were fractionated into CD3+ and CD3- on the FACS and cloned under limiting conditions in the presence of PHA and IL-2. Approximately 90% CD3+ and 10% CD3- cells underwent clonal expansion. Clones obtained from the CD3- fraction bel...

The CD2 co-receptor expressed on the surface of T lymphocytes is able to stimulate T cell activation, proliferation and cytokine production in the absence of direct engagement of the antigen-specific TCR. Engagement of human CD2 by mitogenic pairs of anti-CD2 mAb induces tyrosine phosphorylation of a number of intracellular proteins including a 120 kDa phosphoprotein that we identify as the pro...