Biochemical fractionation and assembly of the membrane components that mediate nascent chain targeting and translocation.
Fractionation of a microsomal detergent extract with ammonium sulfate allows separation of the signal recognition particle receptor (SR alpha), which is required for targeting of the nascent chain, from other microsomal proteins, such as signal peptidase, whose activity is displayed during subsequent translocation. The reconstituted SR alpha-enriched fraction is functional in assays of precursor targeting and elongation arrest release but lacks translocation activity. This defect can be complemented by addition, prior to reconstitution, of a separate protein subfraction. In addition, protein components necessary for translocation can be reversibly depleted from the complementary fraction, under conditions where precursor targeting is retained, by sulfhydryl-directed chromatography. Thus, precursor binding and translocation can be biochemically uncoupled, indicating that they are sequential reactions mediated by distinct components.
Duke Scholars
Altmetric Attention Stats
Dimensions Citation Stats
Published In
DOI
ISSN
Publication Date
Volume
Issue
Start / End Page
Location
Related Subject Headings
- Triticum
- Signal Recognition Particle
- Ribosomes
- Ribonucleoproteins
- Reticulocytes
- Receptors, Peptide
- Receptors, Cytoplasmic and Nuclear
- Receptors, Cell Surface
- RNA, Messenger
- Protein Precursors
Citation
Published In
DOI
ISSN
Publication Date
Volume
Issue
Start / End Page
Location
Related Subject Headings
- Triticum
- Signal Recognition Particle
- Ribosomes
- Ribonucleoproteins
- Reticulocytes
- Receptors, Peptide
- Receptors, Cytoplasmic and Nuclear
- Receptors, Cell Surface
- RNA, Messenger
- Protein Precursors