Open AccessAster proteins mediate carotenoid transport in mammalian cells
Author(s) -
Sepalika Bandara,
Srinivasagan Ramkumar,
Sanae Imanishi,
Linda D. Thomas,
Onkar B. Sawant,
Yoshikazu Imanishi,
Johannes von Lintig
Publication year - 2022
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.2200068119
Subject(s) - carotenoid , zeaxanthin , biology , biochemistry , lutein
Significance Carotenoid pigments accumulate in specific patterns in vertebrate tissues and play important roles as colorants, chromophores, and hormone precursors. However, proteins that facilitate transportation of these lipophilic pigments within cells have not been identified. We provide evidence that Aster proteins are key components for this process and show that they bind the pigments with high affinity. We observed in mice that carotenoids accumulate in tissues that express Aster-B and this accumulation can be prevented by enzymatic turnover by the BCO2 protein. Accordingly, we found opposing expression patterns of the Aster-B protein and BCO2 in the human retina that seemingly contribute to the unique carotenoid concentration in the macula lutea.