Characterization of mammalian heart annexins with special reference to CaBP33 (annexin V)

FEBS Letters

Pula, Grazia¹  Ceccarelli, Paolo¹  Giambanco, Ileana¹  Bianchi, Roberta¹  Donato, Rosario¹ 

[1] Section of Anatomy, Department of Experimental Medicine and Biochemical Sciences, University of Perugia, 06100 Perugia, Italy

关键词: Annexin;    Calcium;    Membrane;    Binding;    Heart;   

DOI  :  10.1016/0014-5793(90)80808-V

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Porcine heart was observed to express annexins V (CaBP33) and VI in large amounts, and annexins III and IV in much smaller amounts. Annexin V (CaBP33) in porcine heart was examined in detail by immunochemistry. Homogenization and further processing of heart in the presence of EGTA resulted in the recovery of annexin V (CaBP33) in the cytosolic fraction and in an EGTA-resistant, Triton X-100-soluble fraction from cardiac membranes. Including Ca²⁺ in the homogenization medium resulted in a significant decrease in the annexin V (CaBP33) content of the cytosolic fraction with concomitant increase in the content of this protein in myofibrils, mitochrondria, the sarcoplasmic reticulum and the sarcolemma. The amount of annexin V (CaBP33) in each of these subfractions depended on the free Ca²⁺ concentration in the homogenizing medium. At the lowest free Ca²⁺ concentration tested, 0.8 μM, only the sarcolemma appeared to contain bound annexin V (CaBP33). Membrane-bound annexins V (CaBP33) and VI partitioned in two fractions, one EGTA-resistant and Triton X-100-extractable, and one Triton X-100-resistant and EGTA-extractable. Altogether, these data suggest that annexins V and VI are involved in the regulation of membrane-related processes.

【 授权许可】

Unknown