Concanavalin A and wheat germ agglutinin are as effective as insulin in enhancing the rate of glucose transport and in inhibiting epinephrine-stimulated lipolysis in isolated adipocytes. These lectins, also like insulin, inhibit basal as well as epinephrine-stimulated adenylate cyclase activity of membranes obtained from homogenates of fat cells. Low concentrations of wheat germ agglutinin enha...

Using nuclear envelopes from Chinese hamster ovary (CHO) cells as an antigen, a mouse monoclonal antibody (IgM; designated mAb CHON211) that specifically binds to components of the nuclear pore complex (nucleoporins) was isolated. Immunofluorescence localization of the antigen recognized by mAb CHON211 revealed a punctate pattern restricted to the nuclear envelope; this pattern changed dramatic...

Transformed and nontransformed cells in tissue culture differ in their rate of uptake of certain nutrients, as determined by a polyester-coverslip technique. A 2.5- to 3.5-fold increased rate of uptake of alpha-aminoisobutyric acid, cycloleucine, and 2-deoxy-D-glucose was observed with polyoma virus-transformed baby hamster kidney (BHK) 21 cells and simian virus 40 (SV40)-transformed BALB/3T3 (...

Glycoproteins of a metastasizing line of B16 mouse mela noma and a poorly metastasizing wheat germ agglutinin-resistant clone were compared. Cell surface proteins and glycoproteins were isotopically labeled by lactoperoxidase-catalyzed iodination and by NaB3H4 reduction after oxidation by periodate or galactose oxidase and subsequently analyzed by gel electrophoresis and autoradiography. Differ...

Retrograde tracing techniques were used to identify supraspinal neurons that project to sacral, lumbar and cervical levels of the spinal cord in the gray short-tailed Brazilian opossum, Monodelphis domestica. Injections of Fast Blue, True Blue or wheat germ agglutinin conjugated to horseradish peroxidase into the sacral or lumbar cord labeled neurons in hypothalamic and brainstem nuclei reporte...

The synthesis, assembly, and processing of the multiple molecular forms of acetylcholinesterase (AcChoEase; acetylcholine acetylhydrolase, EC 3.1.1.7) in quail muscle cultures was studied by using lectins to distinguish enzyme molecules residing in different subcellular compartments. Special emphasis was given to the assembly of asymmetric AcChoEase molecules because these appear to be the pred...

A variety of differences between normal and leukemic cells have been reported, involving such diverse characteristics as alkaline phosphatase content,"' 12 glycolytic rate, and nucleic acid metabolism.6 In most cases, however, the differences observed could have been due to variations in cell maturation levels rather than to leukemia-specific changes. We still do not know whether leukemia resul...

One of the specific inhibitors of calmodulin action, trifluoperazine, blocked the stimulating action of insulin on 2-deoxyglucose uptake and glucose metabolism. The inhibitory effect of insulin on lipolysis was not altered by the drug. The active (insulin-stimulated) state and the basal state of lipogenesis were inhibited half-maximally at 80 and 550 microM trifluoperazine, respectively. 2-Deox...

Lines of KB cells resistant to Sendai virus-induced cytolysis have been isolated and characterized (Toyama, S., Toyama, Su., and Uetake, H. (1977) Virology 76, 503-515). This study is concerned with the nature of this mutation. Plasma membrane fractions from Sil cells were found to have decreased amount of sialic acid and the same amount of galactose as compared to the membranes from parental K...

Cystic fibrosis is associated with mutations of the cystic fibrosis transmembrane regulator (CFTR), a cAMP-regulated plasma membrane Cl- channel. Mutations in the CFTR have been reported to not only impair Cl-transport at the plasma membrane but also inhibit organelle acidification and disrupt cAMP-regulated plasma membrane recycling. Comparisons of cultured pancreatic adenocarcinoma cells expr...