TY - JOUR
T1 - Identification of a novel human sterol-sensitive ATP-binding cassette transporter (ABCA7)
AU - Kaminski, Wolfgang E.
AU - Orsó, Evelyn
AU - Diederich, Wendy
AU - Klucken, Jochen
AU - Drobnik, Wolfgang
AU - Schmitz, Gerd
N1 - Funding Information:
We thank Ulrike Stöckl for expert technical assistance and Dr. G. Chimini, Marseille, for sharing partial mouse sequence information. This work was funded by grants from the Deutsche Forschungsge-meinschaft (AN 111/6-1, “Molekulare Grundlagen der Differen-zierung und Aktivierung mononukleärer Phagozyten”, and KA 1078/ 2-1) and a grant from BAYER AG Pharma-Research, Wuppertal, Germany (Dr. K. D. Bremm). E.O. was supported by the Alexander von Humboldt Foundation.
PY - 2000/7/5
Y1 - 2000/7/5
N2 - We report the identification of the full-length cDNA for a novel ATP-binding cassette (ABC) transporter from human macrophages. The mRNA is of 6.8 kb size and contains an open reading frame encoding a polypeptide of 2146 amino acids with a calculated molecular weight of 220 kDa. The predicted protein product is composed of two transmembrane domains and two nucleotide binding folds indicating that it pertains to the group of full-size ABC transporters. The novel transporter shows highest protein sequence homology with the recently cloned human cholesterol and phospholipid exporter ABCA1 (54%) and the human retinal transporter ABCR (49%), both members of the ABC transporter subfamily A. In accordance with the currently proposed classification, the novel transporter was designated ABCA7. ABCA7 mRNA was detected predominantly in myelo-lymphatic tissues with highest expression in peripheral leukocytes, thymus, spleen, and bone marrow. Expression of ABCA7 is induced during in vitro differentiation of human monocytes into macrophages. In macrophages, both the ABCA7 mRNA and protein expression are upregulated in the presence of modified low density lipoprotein and downregulated by HDL3. Our results suggest a role for ABCA7 in macrophage transmembrane lipid transport. (C) 2000 Academic Press.
AB - We report the identification of the full-length cDNA for a novel ATP-binding cassette (ABC) transporter from human macrophages. The mRNA is of 6.8 kb size and contains an open reading frame encoding a polypeptide of 2146 amino acids with a calculated molecular weight of 220 kDa. The predicted protein product is composed of two transmembrane domains and two nucleotide binding folds indicating that it pertains to the group of full-size ABC transporters. The novel transporter shows highest protein sequence homology with the recently cloned human cholesterol and phospholipid exporter ABCA1 (54%) and the human retinal transporter ABCR (49%), both members of the ABC transporter subfamily A. In accordance with the currently proposed classification, the novel transporter was designated ABCA7. ABCA7 mRNA was detected predominantly in myelo-lymphatic tissues with highest expression in peripheral leukocytes, thymus, spleen, and bone marrow. Expression of ABCA7 is induced during in vitro differentiation of human monocytes into macrophages. In macrophages, both the ABCA7 mRNA and protein expression are upregulated in the presence of modified low density lipoprotein and downregulated by HDL3. Our results suggest a role for ABCA7 in macrophage transmembrane lipid transport. (C) 2000 Academic Press.
UR - http://www.scopus.com/inward/record.url?scp=0033890964&partnerID=8YFLogxK
U2 - 10.1006/bbrc.2000.2954
DO - 10.1006/bbrc.2000.2954
M3 - Article
C2 - 10873640
AN - SCOPUS:0033890964
SN - 0006-291X
VL - 273
SP - 532
EP - 538
JO - Biochemical and Biophysical Research Communications
JF - Biochemical and Biophysical Research Communications
IS - 2
ER -