Inhibition of cellular functions of HIV-1 Nef by artificial SH3 domains.
SH3 domains regulate many normal and pathological cellular processes by guiding specific protein interactions. Studies on binding of HIV-1 Nef to the SH3 domain of the Hck tyrosine kinase have indicated an important role for the SH3 RT-loop region in ligand binding. Here we have tested the potential of artificial Hck-derived SH3 domains carrying tailored RT-loops providing high affinity for Nef as intracellular inhibitors of Nef. These artificial SH3 domains efficiently associated with Nef in cells and thereby potently inhibited SH3-dependent Nef functions, such as association with p21-activated kinase-2 and induction of the transcription factor NFAT. On the other hand, biochemical and functional data indicated that the Nef-targeted SH3 domains were not prone to compete with normal SH3-mediated processes. Thus, RT-loop-modified SH3 domains represent a novel approach for selectively interfering with cellular signaling events, which could be exploited in research as well as in therapeutic applications.
Hiipakka
M
M
Institute of Medical Technology, University of Tampere, Tampere, FIN-33014, Finland.
Huotari
P
P
Manninen
A
A
Renkema
G H
GH
Saksela
K
K
D002460:Cell Line; D015693:Gene Products, nef / Q000235:genetics*; D015316:Genetic Therapy; D015658:HIV Infections / Q000235:genetics / Q000821:virology*; D015497:HIV-1 / Q000502:physiology*; D006801:Humans; D011995:Recombination, Genetic; D013329:Structure-Activity Relationship; D014779:Virus Replication / Q000235:genetics; D054311:nef Gene Products, Human Immunodeficiency Virus; D018909:src Homology Domains / Q000235:genetics
D015693:Gene Products, nef; D054311:nef Gene Products, Human Immunodeficiency Virus