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

Search MEDLINE/PubMed


  • Title: Structural and functional characterization of endonexin II, a calcium- and phospholipid-binding protein.
    Author: Schlaepfer DD, Mehlman T, Burgess WH, Haigler HT.
    Journal: Proc Natl Acad Sci U S A; 1987 Sep; 84(17):6078-82. PubMed ID: 2957692.
    Abstract:
    A protein with an apparent Mr of 33,000 was previously purified from the EGTA eluate of a human placental particulate fraction. We now report the amino acid sequence of approximately one-third of this protein and show that it has extensive homology with a newly defined family of Ca2+-binding proteins termed annexins. The partial sequence of the placental protein could be aligned with the sequence of either lipocortin I or calpactin I such that 49% and 58%, respectively, of the residues were identical. A comparison of the partial sequences of the placental protein with the partial sequence of bovine endonexin revealed 74% sequence identity. Based on this close relationship, the placental protein was named endonexin II. Equilibrium dialysis showed that endonexin II bound Ca2+ (Kd greater than 0.5 mM) and the affinity was increased by phosphatidylserine liposomes (kd approximately equal to 100 microM). In addition, endonexin II bound to phosphatidylserine- and phosphatidylethanolamine-containing liposomes in a Ca2+-dependent manner, and the binding was cooperative with respect to Ca2+ concentration (Hill constant greater than 3). The Ca2+- and phospholipid-binding properties of endonexin II raise the possibility that each of the four internally repeated sequences that have been demonstrated within this family of proteins contains a Ca2+-binding site.
    [Abstract] [Full Text] [Related] [New Search]