Purification of an Inositol 1,4,5-trisphosphate-binding Calreticulin-containing Intracellular Compartment of HL-60 Cells
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To investigate the identity of Ins(1,4,5)P3-sensitive intracellular Ca2+ stores in myeloid cells, we have developed a method that yields subcellular fractions highly enriched in Ins(1,4,5)P3 binding. HL-60 cells were disrupted by nitrogen cavitation, and subcellular fractions were obtained by differential centrifugation, followed by Percoll- and sucrose-density-gradient separations. A subcellular fraction enriched 26-fold in Ins(1,4,5)P3-binding sites was obtained. This fraction showed no enrichment in plasma-membrane markers and only a comparatively moderate enrichment (7-fold) in endoplasmic-reticulum markers. The ratio between specific enrichment of Ins(1,4,5)P3 binding and endoplasmic-reticulum markers in the different fractions varied over 50-fold, from less than 0.1 to greater than 5. The purified Ins(1,4,5)P3-binding fraction was enriched to a similar extent (27-fold) in the putative intravesicular Ca(2+)-storage protein calreticulin. Our results favour the concept of a distinct Ins(1,4,5)P3-binding, calreticulin-containing compartment (i.e. the calciosome) in HL-60 cells.
Calreticulin: one protein, one gene, many functions.
Michalak M, Corbett E, Mesaeli N, Nakamura K, Opas M Biochem J. 1999; 344 Pt 2:281-92.
PMID: 10567207 PMC: 1220642.
Korkotian E, Segal M J Neurosci. 1997; 17(5):1670-82.
PMID: 9030626 PMC: 6573380.
Parys J, Missiaen L, Smedt H, Sienaert I, Casteels R Pflugers Arch. 1996; 432(3):359-67.
PMID: 8765993 DOI: 10.1007/s004240050145.
Intracellular calcium stores and inositol 1,4,5-trisphosphate receptor in rat liver cells.
Lievremont J, Hill A, Tran D, Coquil J, Stelly N, Mauger J Biochem J. 1996; 314 ( Pt 1):189-97.
PMID: 8660282 PMC: 1217024. DOI: 10.1042/bj3140189.
Favre C, Jerstrom P, Foti M, Stendhal O, Huggler E, Lew D Biochem J. 1996; 316 ( Pt 1):137-42.
PMID: 8645196 PMC: 1217313. DOI: 10.1042/bj3160137.