Posttranslational translocation of influenza virus hemagglutinin across microsomal membranes.
The biosynthesis of influenza virus hemagglutinin (HA) and its translocation across microsomal membranes were studied in a mammalian cell-free system. All forms of HA could be cotranslationally translocated with high efficiency. However, only truncated forms of HA were translocated after protein synthesis has been terminated. The efficiency of this posttranslational translocation was dependent on the extent of the truncation. Posttranslational translocation was ribosome dependent and occurred only in the presence of a functional N-terminal signal sequence. The molecular mechanism of protein targeting and translocation across the membrane of the endoplasmic reticulum is discussed.
Chao
C C
CC
Department of Biochemistry, University of Texas Health Science Center, Dallas 75235.
Bird
P
P
Gething
M J
MJ
Sambrook
J
J
D001692:Biological Transport; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics; D004252:DNA Mutational Analysis; D006031:Glycosylation; D006389:Hemagglutinins, Viral / Q000235:genetics / Q000378:metabolism*; D009980:Influenza A virus / Q000378:metabolism*; D007425:Intracellular Membranes / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism*; D008861:Microsomes / Q000378:metabolism*; D014176:Protein Biosynthesis; D011487:Protein Conformation; D011499:Protein Processing, Post-Translational; D021382:Protein Sorting Signals / Q000502:physiology*; D012270:Ribosomes / Q000378:metabolism
D006389:Hemagglutinins, Viral; D008565:Membrane Proteins; D021382:Protein Sorting Signals; D004247:DNA