Worcester Foundation for Biomedical Research

About: Worcester Foundation for Biomedical Research is a based out in . It is known for research contribution in the topics: Estrone & Estrogen. The organization has 2195 authors who have published 2646 publications receiving 115809 citations. The organization is also known as: Worcester Foundation for Experimental Biology.

Molecular characterization of the 50-kD subunit of dynactin reveals function for the complex in chromosome alignment and spindle organization during mitosis

Abstract: Dynactin is a multi-subunit complex which has been implicated in cytoplasmic dynein function, though its mechanism of action is unknown. In this study, we have characterized the 50-kD subunit of dynactin, and analyzed the effects of its overexpression on mitosis in living cells. Rat and human cDNA clones revealed p50 to be novel and highly conserved, containing three predicted coiled-coil domains. Immunofluorescence staining of dynactin and cytoplasmic dynein components in cultured vertebrate cells showed that both complexes are recruited to kinetochores during prometaphase, and concentrate near spindle poles thereafter. Overexpression of p50 in COS-7 cells disrupted mitosis, causing cells to accumulate in a prometaphase-like state. Chromosomes were condensed but unaligned, and spindles, while still bipolar, were dramatically distorted. Sedimentation analysis revealed the dynactin complex to be dissociated in the transfected cultures. Furthermore, both dynactin and cytoplasmic dynein staining at prometaphase kinetochores was markedly diminished in cells expressing high levels of p50. These findings represent clear evidence for dynactin and cytoplasmic dynein codistribution within cells, and for the presence of dynactin at kinetochores. The data also provide direct in vivo evidence for a role for vertebrate dynactin in modulating cytoplasmic dynein binding to an organelle, and implicate both dynactin and dynein in chromosome alignment and spindle organization.

A new acute transforming feline retrovirus and relationship of its oncogene v-kit with the protein kinase gene family

Abstract: A new acute transforming feline retrovirus, the Hardy-Zuckerman 4 feline sarcoma virus (HZ4-FeSV), has been isolated from a feline fibrosarcoma The viral genome of HZ4-FeSV contains a new oncogene designated v-kit, has the structure 5' delta gag-kit-delta pol-delta env 3' and specifies a gag-kit polyprotein of relative molecular mass 80,000 The predicted kit amino-acid sequence displays partial homology with tyrosine-specific protein kinase oncogenes HZ4-FeSV appears to have been generated by transduction of feline c-kit sequences with feline leukaemia virus

Induction of apoptosis in uninfected lymphocytes by HIV-1 tat protein

Abstract: Infection by human immunodeficiency virus-type 1 (HIV-1) is typified by the progressive depletion of CD4 T lymphocytes and deterioration of immune function in most patients. A central unresolved issue in acquired immunodeficiency syndrome (AIDS) pathogenesis is the mechanism underlying this T cell depletion. HIV-1 Tat protein was shown to induce cell death by apoptosis in a T cell line and in cultured peripheral blood mononuclear cells from uninfected donors. This Tat-induced apoptosis was inhibitable by growth factors and was associated with enhanced activation of cyclin-dependent kinases.

Pharmacokinetics, biodistribution, and stability of oligodeoxynucleotide phosphorothioates in mice

Abstract: We describe preliminary studies of the pharmacokinetics, biodistribution, and excretion of an oligodeoxy-nucleotide phosphorothioate ([S]oligonucleotide) in mice. After either intravenous or intraperitoneal administration of a single dose (30 mg/kg of body weight), [S]oligonucleotide (35S-labeled at each internucleotide linkage) was found in most of the tissues for up to 48 hr. About 30% of the dose was excreted in urine within 24 hr, irrespective of the mode of administration; the excreted [S]oligonucleotide was found to be extensively degraded. In plasma, stomach, heart, and intestine, the [S]oligonucleotide was degraded by only 15%, whereas in the kidney and liver degradation was about 50% in 48 hr. The surprising observation was made that chain length extension of administered [S]oligonucleotide occurred in kidney, liver, and intestine. These results provide an initial definition of parameters for the pharmaceutical development of antisense oligonucleotides.