title: Actin filaments play an essential role for transport of nascent HIV-1 proteins in host cells.
abstract: To investigate the role of actin filaments (F-actin) for human immunodeficiency virus type 1 (HIV-1) production in host cells, the effect of mycalolide B that is a novel actin-depolymerizing marine toxin was examined. Mycalolide B blocked the production of HIV-1 from primary infected T-lymphoblastoid and clonically infected monocytoid cells in a concentration-dependent manner. In the presence of 10 microM of mycalolide B, F-actins were disorganized and mostly disappeared in the host cells, and viral envelope- and capsid-proteins did not reach the plasma membrane, but were distributed in the cytoplasm forming aggregates. In electron micrographs, no HIV-1 virions were detected on the cell surface, but many lysosome-like vesicles containing electron dense granules were observed in the cytoplasm, implying that mycalolide B did not disturb the synthesis of viral proteins, but rather inhibited their transport processes of HIV-1 in the host cells.
authors.affiliation: Division of Molecular Cell Biology, Institute of DNA Medicine, The Jikei University School of Medicine, Minato-ku, Tokyo 105-8461, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Sasaki
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ozaki
authors.forename: Hideaki
authors.initials: H
authors.lastname: Karaki
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Nonomura
mesh_terms: D008841:Actin Cytoskeleton / Q000187:drug effects / Q000502:physiology*; D002460:Cell Line; D015638:Cytochalasin D / Q000494:pharmacology; D015497:HIV-1 / Q000254:growth & development*; D006801:Humans; D008387:Marine Toxins; D009000:Monocytes / Q000187:drug effects / Q000821:virology; D010080:Oxazoles / Q000494:pharmacology; D021381:Protein Transport / Q000187:drug effects; D012191:Retroviridae Proteins / Q000378:metabolism*; D013601:T-Lymphocytes / Q000187:drug effects / Q000821:virology
chemical_list: D008387:Marine Toxins; D010080:Oxazoles; D012191:Retroviridae Proteins; C080978:mycalolide B; D015638:Cytochalasin D