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: Purification of calpain II from rat lens and determination of endogenous substrates.
    Author: David LL, Shearer TR.
    Journal: Exp Eye Res; 1986 Mar; 42(3):227-38. PubMed ID: 3011481.
    Abstract:
    Calpain II (EC 3.4.22.17), a calcium-dependent neutral protease, was purified approximately 7000-fold from the soluble of rat lens. The estimated molecular weight of rat lens calpain II was 120,000, and the enzyme was composed of 80,000 and 28,000 MW subunits. Calpain II required 400 microM calcium, a reducing agent, and pH = 7.5 for maximal activity. The enzyme could not be activated by magnesium, and was inhibited by leupeptin and iodoacetate, but not by phenylmethylsulfonyl fluoride. Purified calpain II degraded rat alpha, beta H-, and beta L-crystallins, insoluble proteins, and intrinsic membrane proteins, gamma-Crystallin was not degraded. The proteolysis caused by purified calpain II was similar to proteolysis occurring during the formation of several experimental cataracts in rodents; this suggested that the enzyme may play a role in cataract formation.
    [Abstract] [Full Text] [Related] [New Search]