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 and characterization of a phosphatidylinositol 4-kinase activator in carrot cells.
    Author: Yang W, Burkhart W, Cavallius J, Merrick WC, Boss WF.
    Journal: J Biol Chem; 1993 Jan 05; 268(1):392-8. PubMed ID: 8380160.
    Abstract:
    A phosphatidylinositol 4-kinase activator (PIK-A49) has been purified from carrot cells grown in suspension culture. The activator was purified from a soluble fraction using DEAE-Sepharose CL-6B and S-Sepharose chromatography columns. PIK-A49 has a relative molecular mass of 49 kDa determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The A50 for the activation of the Triton X-100-solubilized phosphatidylinositol 4-kinase fraction was 0.1 microM. Maximal activation was 3-4-fold. The analysis of the sequences of seven peptide fragments containing a total of 142 amino acid residues indicated that PIK-A49 was 69% identical to an actin-binding protein (ABP-50) from Dictyostelium and > 90% identical to elongation factor-1 alpha (EF-1 alpha) from carrot, tomato, and Arabidopsis. PIK-A49 bound actin and facilitated actin polymerization. Poly(U)-directed polyphenylalanine synthesis assays indicated that PIK-A49 had EF-1 alpha activity. The EF-1 alpha activity was enhanced by rabbit EF-1 beta gamma. Activation of phosphatidylinositol 4-kinase by a protein that binds actin and that has EF-1 alpha activity provides additional complexity to the signal transduction mechanisms involving inositol phospholipid metabolism.
    [Abstract] [Full Text] [Related] [New Search]