title: Stress- and sequence-dependent release into the culture medium of HIV-1 Nef produced in Saccharomyces cerevisiae.
abstract: We have produced human immunodeficiency virus type 1 (HIV-1) Nef (a myristylated 206-amino-acid protein) in Saccharomyces cerevisaie and shown that, while Nef is normally found as a predominantly intracellular protein, amounts up to 40 micrograms/ml of Nef are also released into the extracellular medium during stress. By electrophoretic (SDS-PAGE) analysis the extracellular Nef is indistinguishable from intracellular Nef. Conditions of stress that lead to the release of Nef include elevated levels of copper or magnesium ions or growth at elevated temperatures. This release appears to be dependent upon the N-terminal sequences of Nef, including the presence of a myristylation site. Our observations concerning Nef release in yeast suggest new ways in which the behaviour of Nef should be examined in order to gain further insights into the development of AIDS. If the release of Nef is important in the development of AIDS, our work reveals that Nef-associated symptoms may be reduced or delayed by reducing stresses, such as fevers.
authors.affiliation: Biomolecular Research Institute, Parkville, Victoria, Australia.
authors.forename: I G
authors.initials: IG
authors.lastname: Macreadie
authors.forename: L A
authors.initials: LA
authors.lastname: Castelli
authors.forename: A
authors.initials: A
authors.lastname: Lucantoni
authors.forename: A A
authors.initials: AA
authors.lastname: Azad
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D003300:Copper / Q000494:pharmacology; D015693:Gene Products, nef / Q000737:chemistry / Q000378:metabolism*; D015497:HIV-1 / Q000737:chemistry*; D006358:Hot Temperature; D008274:Magnesium / Q000494:pharmacology; D008969:Molecular Sequence Data; D019814:Myristic Acid; D009227:Myristic Acids / Q000378:metabolism; D011499:Protein Processing, Post-Translational; D011994:Recombinant Proteins / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D054311:nef Gene Products, Human Immunodeficiency Virus
chemical_list: D015693:Gene Products, nef; D009227:Myristic Acids; D011994:Recombinant Proteins; D054311:nef Gene Products, Human Immunodeficiency Virus; D019814:Myristic Acid; D003300:Copper; D008274:Magnesium