Open AccessAssociation of Human Immunodeficiency Virus Nef Protein with Actin is Myristoylation Dependent and Influences its Subcellular Localization
Author(s) -
Fackler Oliver T.,
Kienzle Norbert,
Kremmer Elisabeth,
Boese Annette,
Schramm Birgit,
Klimkait Thomas,
Kücherer Claudia,
MuellerLantzsch Nikolaus
Publication year - 1997
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1997.00843.x
Subject(s) - myristoylation , actin , colocalization , biology , cytoskeleton , microbiology and biotechnology , human immunodeficiency virus (hiv) , actin cytoskeleton , subcellular localization , cell fractionation , virology , cell , biochemistry , cytoplasm , enzyme , phosphorylation
Human immunodeficiency virus (HIV) Nef functions are thought to be mediated via interactions with cellular proteins. Utilizing zone velocity sedimentation in glycerol gradients we found that recombinant HIV‐1 Nef non‐covalently associates with actin forming a high‐molecular‐mass complex of 150–300 kDa. This Nef/actin complex was present in human B and T lymphocytes but not in insect cells and was dependent on the N‐terminal myristoylation of Nef, whereas the SH3‐binding proline motif of Nef was not involved. Despite being myristoylated, HIV‐2 Nef did not associate with actin. This might reflect differences in the subcellular localization of Nef since cell‐fractionation experiments revealed that HIV‐ 1Nef was virtually exclusively localized in the cytoskeletal (detergent‐insoluble) fraction whereas HIV‐ 2 Nef had significantly reduced affinity for the cytoskeleton. Colocalization experiments in HIV‐1‐in‐fected CD4+ fibroblasts revealed that Nef/actin complexes may also exist in HIV‐infected cells. This novel interaction of HIV‐1 Nef with actin provides insight into the association of Nef with cellular structures and reveals general differences in the interactions of the Nef proteins from HIV‐1 and HIV‐2.