The endoplasmic reticulum (ER) contains a family of luminal proteins (reticuloplasmins) that are normally excluded from the secretory pathway. However, reticuloplasmins are efficiently secreted when murine fibroblasts are treated with calcium ionophores. The secreted and cellular forms of endoplasmin are clearly distinguishable on the basis of gel mobility… (More)
In lymphocytes and P3 myeloma cells, cross-linking of surface Ig by the capping and patching phenomenon has been used to demonstrate the induction of a specific association between surface Ig and cellular actin.
Valosin-containing protein, VCP/p97 or Cdc48, is a eukaryotic ATPase involved in membrane fusion, protein transport, and protein degradation. We describe two proteins, Ubx2 and Ubx3, which interact with Cdc48 in fission yeast. Ubx3 is the ortholog of p47/Shp1, a previously described Cdc48 cofactor involved in membrane fusion, whereas Ubx2 is a novel… (More)
P815 cells spontaneously shed material (exfoliate) in which actin is the major protein. The exfoliate also contains H-2. The association between actin and H-2 is stable even in the presence of detergent, indicating that protein-protein interactions exist between the actin and H-2. The exfoliate probably consists of highly purified microvilli.
The relationships between resistance to adriamycin, vincristine, colchicine and etopside, expression of P-glycoprotein and CP22 (sorcin), and resistance modification by verapamil and cyclosporin A have been studied in a panel of multidrug-resistant (MDR) mouse tumour cell lines. Whereas there was a generally good correlation between the degree of resistance… (More)
Comparative fingerprinting of the Con A acceptor glycoproteins of cultured tumour cell lines has revealed that the patterns obtained from different cell lines are generally different (Koch & Smith, 1982). This raised the possibility that the glycoprotein maps could prove useful in the classification of tumours and may even aid in the preparation of specific… (More)
The Con A acceptor glycoproteins of murine and human tumour cell lines revealed by two-dimensional fingerprinting on polyacrylamide gels fall into two main categories: constant glycoproteins expressed by all cell lines and variable glycoproteins which are only expressed by particular tumour cell lines. Since the number of variable glycoproteins on a typical… (More)
Plasma membranes isolated from two immunogenic, non-cross-protecting, MC sarcomas were shown to retain the specific rejection antigens of whole cells as well as serologically detected H-2 antigens. Solubilization of the membranes with sodium deoxycholate gave quantitative release of H-2 and retained the rejection specificity of the tumour from which it was… (More)
A method for the extraction of human beta-casomorphin-8 immunoreactive material from human plasma and a radioimmunoassay for its determination in the plasma extracts were developed. Blood was collected from 34 men, from 35 non-pregnant women, from 35 pregnant women and from 138 women after delivery and plasma extracts were assayed for the presence of human… (More)
Protein synthesis, amino acid uptake, membrane potential, cell volume, Na+ and K+ levels, and ATPase (Na+,K+ activated; EC 22.214.171.124) activity were investigated in control and poliovirus-infected HeLa cells. Inhibition of protein synthesis was first observed 60 min postinfection and reached a maximum at 120 min. The onset of protein synthesis inhibition… (More)