>gnl|CDD|72993 cd03234, ABCG_White, The White subfamily represents ABC transporters homologous to the Drosophila white gene, which acts as a dimeric importer for eye pigment precursors. The eye pigmentation of Drosophila is developed from the synthesis and deposition in the cells of red pigments, which are synthesized from guanine, and brown pigments, which are synthesized from tryptophan. The pigment precursors are encoded by the white, brown, and scarlet genes, respectively. Evidence from genetic and biochemical studies suggest that the White and Brown proteins function as heterodimers to import guanine, while the White and Scarlet proteins function to import tryptophan. However, a recent study also suggests that White may be involved in the transport of a metabolite, such as 3-hydroxykynurenine, across intracellular membranes. Mammalian ABC transporters belonging to the White subfamily (ABCG1, ABCG5, and ABCG8) have been shown to be involved in the regulation of lipid-trafficking mechanisms in macrophages, hepatocytes, and intestinal mucosa cells. ABCG1 (ABC8), the human homolog of the Drosophila white gene is induced in monocyte-derived macrophages during cholesterol influx mediated by acetylated low-density lipoprotein. It is possible that human ABCG1 forms heterodimers with several heterologous partners.. Length = 226

 Score = 63.3 bits (154), Expect = 6e-11
 Identities = 61/227 (26%), Positives = 109/227 (48%), Gaps = 14/227 (6%)

Query: 7   LRAKIVDTDTEIIRGLNLKVEPSEVVAIMGPNGSGKSTLSYLLSGH-KDYEITAGDILYK 65
           L+AK  +    I+  ++L VE  +V+AI+G +GSGK+TL   +SG  +    T+G IL+ 
Sbjct: 11  LKAKNWNKYARILNDVSLHVESGQVMAILGSSGSGKTTLLDAISGRVEGGGTTSGQILFN 70

Query: 66  GESILDWSIVERASKGIFLAFQYPVEIPGIIMMQFLKIALNEQRKARNEKELLIPDFTRK 125
           G+        +  +   ++  Q  + +PG+ + + L      +   ++       D  RK
Sbjct: 71  GQPRKPDQFQKCVA---YVR-QDDILLPGLTVRETLTYTAILRLPRKS------SDAIRK 120

Query: 126 VR-KITAELGINMDMLKRPLNLGFSGGEKKIAEILQMRLLEPSLCILDETDSGLD-IDAL 183
            R +      + +  +   L  G SGGE++   I    L +P + ILDE  SGLD   AL
Sbjct: 121 KRVEDVLLRDLALTRIGGNLVKGISGGERRRVSIAVQLLWDPKVLILDEPTSGLDSFTAL 180

Query: 184 KIAAQGVNALRSQDRSFLIITHYQRLLNYIKPDTIHVLHNGKIIKTG 230
            +    ++ L  ++R  ++  H  R   +   D I +L +G+I+ +G
Sbjct: 181 NL-VSTLSQLARRNRIVILTIHQPRSDLFRLFDRILLLSSGEIVYSG 226