Ephrins are cell surface associated ligands for Eph receptor tyrosine kinases and are implicated in repulsive axon guidance, cell migration, topographic mapping and angiogenesis. During the past year, Eph receptors have been shown to associate with glutamate receptors in excitatory neurons, suggesting a role in synapse formation or function. Moreover,… (More)
Recent studies have shown that the formation of boundaries between the segments - rhombomeres - of the vertebrate hindbrain depends on bidirectional signalling between neighbouring cells. This signalling is mediated by Eph receptors and their ligands, which has been found to restrict cell intermingling in vitro.
PolyADP-ribosylation is a transient posttranslational modification of proteins, mainly catalyzed by poly(ADP-ribose)polymerase-1 (PARP-1). This highly conserved nuclear protein is activated rapidly in response to DNA nick formation and promotes a fast DNA repair. Here, we examine a possible association between polyADP-ribosylation and the activity of… (More)
Malignant melanoma cells express the vitamin D receptor (VDR). However, some melanoma cell lines fail to respond to the antiproliferative effects of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3). We reported previously that out of seven melanoma cell lines analyzed, three cell lines (MeWo, SK-Mel28, SM) respond to the antiproliferative effects of 1,25(OH)2D3,… (More)
The transformed clonal isolates of Indian muntjac diploid cells by a mouse sarcoma virus, 43-2XV, were tested for tumorigenicity in athymic nude mice. In spite of the indistinguishable transformed morphology, the tumorigenicity exhibited four different patterns: (a) no tumor formation; (b) slowly growing regressive tumor formation; (c) rapidly growing… (More)