세포막 정보전달 과정에 참여하는 효소로 inositol triphosphatc(InsP₃)를 분해하는 InsP₃, kinase를 소의 뇌 조직으로 부터 새로운 정제방법을 개발하고 isozyme들의 특성을 관찰하여 다음과 같은 결과를 얻었다. 분쇄한 소의 뇌조직을 PEG로 단백침전하고 DEAE cellulose chromatography 하여 InsP₃, kinase I , II 의 두 isozyme을 얻었으며, 각각의 isozyme분획을 Matrix green gel 및 calmodulin-Affigel 15column으로 chromatography하였다. Phenyl-TSKHPLC하여 정제하였으며 1은 3,103배, II는 2,310 배의 정체를 나타내었다. 정제 단계에서 specific activity를 비교해 볼때 Matrix green gel chromatography가 DEAE cellulose에서 보다 I 이 30배, II가 약 2.3배로 나타났고 정제배수도 I 이 17.2% 에서 62.1%로 II 가 16.6%애서 38%로나왔으나 calmodulin-Affigel 15과 비교시는 큰 차이가, 없었다. 그러므로 Matrix green gel이 정제에서 매우 중요한 단계라 할 수 있다. 효소의 분자량을 알기 위하여 DEAE HPLC로 두 개의 isozyme을 분리하여 전기영동한 결과 I 은 분자량 145,000, 85,500 및 69,500의 3개의 단백질을 얻었고 II 는 분자량 79,000 및 57,000의 2개의 단백질을 얻었다.

Inositol 1,4,5-triphosphate(InsP₃) is a second messenger for mobilizing intracellular Ca²⁺. It can be dephosphorylated by soluble and particulate forms on InsP₃, 5-phosphatase, or phosphorylated to produce inositol 1,3,4,5-tetrakisphosphate(InsP₃) by InsP₃, 3-kinase. These enzymes represent possible targets for the regulation of the InsP₃/InsP₄ signal. InsP₃, 3-kinase which catalyses th ATP-dependent phosphorylation of InsP₃ was purified from bovine brain tissue. All operation were carried out at 4℃. Fresh tissure was homogenized and centrifuged. The supernatant was pooled. Proteins were precipitated from 10% polyethylene glycol, and suspended solution was applied to DEAE cellulose column for chromatography. As the result of above procedure, two isozymes of InsP₃, 3-kinase, I and II were obtained. Each isozyme was applied to Matriz green gel, Calmodulin-Affigel 15 column and subsequent phenyl-TSK HPLC column. Specific activites(SA) and fold of puriety were observed at each purification step of chromatography. At DEAE cellulose chromatography, SA were J, 0.6 and IT, 4.8 nM/min/mg, and folds were I, 17.2 and II, 16.6. At Matrix green gel chromatography, SA were I, 18 and II, 11 nM/min/mg, folds were I, 62.1 and II, 38.0. At calmodulin-Affigel 15 column chromatography, SA were I, 19 and II , 13 nM/min/mg, folds were I, 65.5 and II, 44.8. Finally InsP₃, kinase I and II were purified 3,103-fold and 2,310-fold, and SA were I, 900 and II, 670 nM/min/mg, respectively. SDS-polyacrylamide gel electrophoresis elucidated 3 distinct fractions of Mr of 145,000, 85,000 and 69,500 from isozyme I, and 2 distinct fractions of Mr of 79,000 and 57,000 from isozyme II.