The C-terminal transmembrane domain of human phospholipid scramblase 1 is essential for the protein flip-flop activity and Ca2+-binding

被引：16

作者：

Sanchez-Magraner, Lissete ^{[1
,2
,3
]}

Posada, Itziar M. D. ^{[1
,2
]}

Andraka, Nagore ^{[1
,2
]}

Xabier Contreras, F. ^{[1
,2
]}

Viguera, Ana R. ^{[1
,2
]}

Guerin, Diego M. A. ^{[1
,2
]}

Arrondo, Jose L. R. ^{[1
,2
]}

Monaco, Hugo L. ^{[3
]}

Goni, Felix M. ^{[1
,2
]}

机构：

[1] Univ Basque Country, CSIC, UPV EHU, Unidad Biofis, E-48080 Bilbao, Spain

[2] Univ Basque Country, Dept Bioquim, E-48080 Bilbao, Spain

[3] Univ Verona, Dept Biotechnol, I-37134 Verona, Italy

来源：

JOURNAL OF MEMBRANE BIOLOGY | 2014年 / 247卷 / 02期

关键词：

Transmembrane lipid motion; Phospholipid scramblase 1; Calcium binding protein; TRANSBILAYER MOVEMENT; PLASMA-MEMBRANE; CALCIUM-IONS; PHOSPHOLIPID-SCRAMBLASE-1; STABILITY; RECEPTOR; ALPHA; PHOSPHATIDYLSERINE; PALMITOYLATION; IDENTIFICATION;

D O I：

10.1007/s00232-013-9619-7

中图分类号：

Q5 [生物化学]; Q7 [分子生物学];

学科分类号：

071010 ; 081704 ;

摘要：

Human phospholipid scramblase 1 (SCR) is a 318 amino acid protein that was originally described as catalyzing phospholipid transbilayer (flip-flop) motion in plasma membranes in a Ca2+-dependent, ATP-independent way. Further studies have suggested an intranuclear role for this protein in addition. A putative transmembrane domain located at the C terminus (aa 291-309) has been related to the flip-flop catalysis. In order to clarify the role of the C-terminal region of SCR, a mutant was produced (SCR Delta) in which the last 28 amino acid residues were lacking, including the alpha-helix. SCR Delta had lost the scramblase activity and its affinity for Ca2+ was decreased by one order of magnitude. Fluorescence and IR spectroscopic studies revealed that the C-terminal region of SCR was essential for the proper folding of the protein. Moreover, it was found that Ca2+ exerted an overall destabilizing effect on SCR, which might facilitate its binding to membranes.

引用

页码：155 / 165

页数：11

共 39 条

[1] Phospholipid scramblase 1 modulates a selected set of IgE receptor-mediated mast cell responses through LAT-dependent pathway [J].