D-myo-inositol 1,4,5-trisphosphate-binding proteins in rat brain membranes

Masako Yoshida, Takashi Kanematsu, Yutaka Watanabe, Toshitaka Koga, Shoichiro Ozaki, Sadaaki Iwanaga, Masato Hirata

Research output: Contribution to journalArticlepeer-review

61 Citations (Scopus)


Rat brain membrane fractions obtained using Triton X-100 were applied to a D-myo-inositol 1,4,5-trisphosphate [D-Ins(1,4,5)P3] immobilized column, followed by gel filtration and anion-exchange chromatography. Two proteins with molecular masses of 130 and 85 kDa, as assessed by SDS-polyacrylamide gel electrophoresis, were purified to apparent homogeneity as D-[3H] Ins(1,4,5)P3-binding proteins with no D-Ins(1,4,5)P3-metabolizing activity. Partial amino acid sequence determinations of these proteins revealed that the 130 kDa protein appears to be a new D-Ins(1,4,5)P3-binding protein and the 85 kDa protein is δ1-isozyme of phospholipase C. We have previously purified 130 and 85 kDa proteins, as D-[3H]Ins(1, 4, 5)P3-binding proteins, from rat brain cytosol fraction. Antibodies against the 130 kDa protein from the cytosol cross-reacted with the membrane 130 kDa protein purified in this study, suggesting that the membrane 130 kDa protein is likely to be the same as the protein from the cytosol fraction. The inhibition of D-[3H]Ins(1,4,5)P3 binding by D-isomers of inositol phosphates available clarified that the 130 kDa protein has a similar affinity for D-Ins(1,4,5,6)P4 to that for D-Ins(1,4,5)P3, while the 85 kDa protein is specific to D-Ins(1,4,5)P3.

Original languageEnglish
Pages (from-to)973-980
Number of pages8
JournalJournal of biochemistry
Issue number5
Publication statusPublished - May 1994

All Science Journal Classification (ASJC) codes

  • Biochemistry
  • Molecular Biology


Dive into the research topics of 'D-myo-inositol 1,4,5-trisphosphate-binding proteins in rat brain membranes'. Together they form a unique fingerprint.

Cite this