Hirsch, Stephan; Muckel, Eva; Heemeyer, Frank; Heijne, Gunnar von; Soll, Jürgen
A Receptor Component of the Chloroplast Protein Translocation Machinery.
The chloroplast outer envelope protein OEP86 functions as a receptor in precursor protein
translocation into chloroplasts. Sequence analysis suggests that the precursor of OEP86
is directed to the chloroplast outer envelope by a cleavable, negatively charged, and
unusually long amino-terminal peptide. This presequence is unlike other potential targeting
signals and suggests the existence of another membrane insertion pathway.
Insertion of precursor OEP86 required the hydrolysis of adenosine triphosphate and the
existence of surface exposed chloroplast membrane components, and it was not competed
by another precursor protein destined for the internal plastid compartments.