These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Hen oviduct signal peptidase is an integral membrane protein.
    Author: Lively MO, Walsh KA.
    Journal: J Biol Chem; 1983 Aug 10; 258(15):9488-95. PubMed ID: 6348046.
    Abstract:
    Membrane preparations from rough endoplasmic reticulum of hen oviduct resemble those of dog pancreas in their capacity to translocate nascent secretory proteins into membrane vesicles present during cell-free protein synthesis. As with the dog membranes, the precursor form of human placental lactogen is transported into the vesicles and processed to the native secretory form by an associated "signal peptidase." The oviduct microsomal membranes glycosylate nascent ovomucoid and ovalbumin in vitro. Attempts to extract the signal peptidase from these membrane vesicles revealed that it is one of the least easily solubilized proteins. A protocol for enrichment of signal peptidase was developed that took advantage of its tight association with these vesicles. These studies indicate that the enzyme has the characteristics of an integral membrane protein which remains active in membrane vesicles even after extraction with low concentrations of detergent that do not dissolve the lipid bilayer or after disruption of membrane vesicles in ice-cold 0.1 M Na2CO3, pH 11.5 (Fujiki, Y., Hubbard, A. L., Fowler, S., and Lazarow, P.B. (1982) J. Cell Biol. 93, 97-102), which releases the majority of membrane-associated proteins. Solubilization requires concentrations of nondenaturing detergents that totally dissolve the lipid bilayer. The detergent-solubilized enzyme retains the activity and the characteristic specificity of the membrane-bound form.
    [Abstract] [Full Text] [Related] [New Search]