ABCMdb

ABCA1 p.Thr1243Asp

Predicted by SNAP2:	A: D (75%), C: D (80%), D: D (85%), E: D (91%), F: D (85%), G: D (80%), H: D (85%), I: D (85%), K: D (85%), L: D (85%), M: D (85%), N: D (59%), P: D (66%), Q: D (80%), R: D (85%), S: N (72%), V: D (85%), W: D (91%), Y: D (85%),
Predicted by PROVEAN:	A: N, C: D, D: N, E: D, F: D, G: D, H: D, I: D, K: D, L: D, M: D, N: N, P: N, Q: D, R: D, S: N, V: D, W: D, Y: D,

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Publications
[hide] Phosphorylation by protein kinase CK2 modulates th... J Biol Chem. 2004 Sep 3;279(36):37779-88. Epub 2004 Jun 24. Roosbeek S, Peelman F, Verhee A, Labeur C, Caster H, Lensink MF, Cirulli C, Grooten J, Cochet C, Vandekerckhove J, Amoresano A, Chimini G, Tavernier J, Rosseneu M
Phosphorylation by protein kinase CK2 modulates the activity of the ATP binding cassette A1 transporter.
J Biol Chem. 2004 Sep 3;279(36):37779-88. Epub 2004 Jun 24., [PMID:15218032]

Abstract [show]
In a previous characterization of the ABCA subfamily of the ATP-binding cassette (ABC) transporters, we identified potential protein kinase 2 (CK2) phosphorylation sites, which are conserved in eukaryotic and prokaryotic members of the ABCA transporters. These phosphorylation residues are located in the conserved cytoplamic R1 and R2 domains, downstream of the nucleotide binding domains NBD1 and NBD2. To study the possible regulation of the ABCA1 transporter by CK2, we expressed the recombinant cytoplasmic domains of ABCA1, NBD1+R1 and NBD2+R2. We demonstrated that in vitro ABCA1 NBD1+R1, and not NBD2+R2, is phosphorylated by CK2, and we identified Thr-1242, Thr-1243, and Ser-1255 as the phosphorylated residues in the R1 domain by mass spectrometry. We further investigated the functional significance of the threonine and serine phosphorylation sites in NBD1 by site-directed mutagenesis of the entire ABCA1 followed by transfection into Hek-293 Tet-Off cells. The ABCA1 flippase activity, apolipoprotein AI and AII binding, and cellular phospholipid and cholesterol efflux were enhanced by mutations preventing CK2 phosphorylation of the threonine and serine residues. This was confirmed by the effect of specific protein kinase CK2 inhibitors upon the activity of wild type and mutant ABCA1 in transfected Hek-293 Tet-Off cells. The activities of the mutants mimicking threonine phosphorylation were close to that of wild type ABCA1. Our data, therefore, suggest that besides protein kinase A and C, protein kinase CK2 might play an important role in vivo in regulating the function and transport activity of ABCA1 and possibly of other members of the ABCA subfamily.

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No. Sentence Comment
94 Similar measurements were performed in the presence of 50 ␮M 4,5,6,7-tetrabromobenzotriazole and apigenin CK2 inhibitors on Mock-transfected and Hek-293 cells transfected with WT ABCA1 and with the T1242A, T1243A, T1242A/T1243A, and T1242D/T1243D ABCA1 mutants. Login to comment
134 Mutants were also designed to mimic phosphorylated residues as T1242D, T1243D, T1242D/T1243D. Login to comment
162 The effect of the specific CK2 inhibitors 4,5,6,7-tetrabromo- benzotriazole and apigenin on the flippase activity in Hek-293 Tet-Off cells transfected with WT ABCA1 and with the T1242A, T1243A, T1242A/T1243A, S1255A, and T1242D/ T1243D mutants was consistent with the above data. Login to comment
177 This increase was more pronounced for the T1243A mutation either alone or in combination with the T1242A mutation, whereas the effect of the T1242A and S1255A mutants was similar. Login to comment
179 The T1242D, T1243D, T1242D/T1243D mutations, which mimic CK2 phosphorylation, had an opposite effect to the Thr-Ala mutations, as apoprotein binding to cells transfected with these mutants amounted to around 110% of WT ABCA1. Login to comment
197 The T1242D, T1243D, and T1242/ T1243D mutations had an opposite effect as the efflux induced by that mutant was close to WT ABCA1. Login to comment
92 Similar measurements were performed in the presence of 50 òe;M 4,5,6,7-tetrabromobenzotriazole and apigenin CK2 inhibitors on Mock-transfected and Hek-293 cells transfected with WT ABCA1 and with the T1242A, T1243A, T1242A/T1243A, and T1242D/T1243D ABCA1 mutants. Login to comment
132 Mutants were also designed to mimic phosphorylated residues as T1242D, T1243D, T1242D/T1243D. Login to comment
160 The effect of the specific CK2 inhibitors 4,5,6,7-tetrabromo- benzotriazole and apigenin on the flippase activity in Hek-293 Tet-Off cells transfected with WT ABCA1 and with the T1242A, T1243A, T1242A/T1243A, S1255A, and T1242D/ T1243D mutants was consistent with the above data. Login to comment
195 The T1242D, T1243D, and T1242/ T1243D mutations had an opposite effect as the efflux induced by that mutant was close to WT ABCA1. Login to comment