Eyes are windows of the soul, eye diseases greatly undermine the quality of life. I have a long-lasting focus on elucidating the mechanisms of macular degenerative diseases at a molecular level. The main findings include: 1)studies on the structure-function relationship of the photoreceptor specific ABC transporter ABCA4, which provide a molecular based rationale for the phenotype displayed by patients with disease-associated mutations in this region of ABCA4; 2) research on STRA6-the membrane receptor for retinol binding protein (RBP) and STRA6 mediated vitamin A transport, which proves that vitamin A (despite being a hydrophobic molecule) crosses the membrane through a transmembrane “pore” within STRA6; 3) identification of PLXDC1 and PLXDC2 as the specific cell membrane receptors for pigmented epithelium derived factor, which makes it possible to develop small-molecule drugs based on receptor functions for treatment of macular degenerative diseases and diabetic retinopathy.

Kawaguchi R, Zhong M, Kassai M,Ter-Stepanian M, Sun H (2015). Vitamin A Transport Mechanism of theMultitransmembrane Cell-Surface Receptor STRA6. Membranes (Basel) 5(3):425-53.

ZhongM,Hui Sun H (2015). A Genetic Clog in the Vitamin A Transport Machinery. Cell.161: 3 435-437.

ChengG *, Zhong M *, Kawaguchi R *, Kassai M, Muayyad Al-Ubaidi M, Deng J,Ter-Stepanian M, Sun H (2014). Identification of PLXDC1 and PLXDC2 as thetransmembrane receptors for the multifunctional factor PEDF. eLife 3 :e05401.(*此三作者贡献相等)

ZhongM, Kawaguchi R, Kassai M, Sun H (2014) Apo-RBP, Holo-RBP, andInsulin Resistance. Molecular and Cellular Biology. 34:11 2105-2106

TerraR, Wang X, Hu Y, Charpentier T, Lamarre A, Zhong M, Sun H, Mao J, Qi S,Luo H, Wu J (2013). To Investigate the Necessity of STRA6 Upregulation in TCells during T Cell Immune Responses. PLoS One. 8(12): e82808.

ZhongM, Kawaguchi R, Mariam Ter-Stepanian, Miki Kassai, Hui Sun*VitaminA transport and the transmembrane pore in the cell-surface receptor for plasmaretinol binding protein. PLoS One. 8(11):e73838.

KawaguchiR, Zhong M, Kassai M, Ter-Stepanian M, Sun H (2013). Differential andIsomer-specific Modulation of Vitamin A Transport and the Catalytic Activitiesof the RBP Receptor by Retinoids. J Membr Biol. 246(8):647-60.

KawaguchiR, Zhong M, Sun H (2013). Real-time Analyses of Retinol Transport by theMembrane Receptor of Plasma Retinol Binding Protein. J Vis Exp (71), e50169.

KawaguchiR, Zhong M, Kassai M, Ter-Stepanian M and Sun H (2012). STRA6-CatalyzedVitamin A Influx, and Exchange. J Membrane Biol. 245(11):731-45.

ZhongM, Kawaguchi R, Kassai M and Sun H (2012). Retina, Retinol,Retinal and the Natural History of Vitamin A as a Light Sensor. Nutrients.4(12), 2069-2096, Review.

KawaguchiR, Yu J, Ter-Stepanian M, Zhong M, Cheng G, Yuan Q, Jin M, Travis GH,Ong D, Sun H (2011). Receptor-mediated cellular uptake mechanism that couplesto intracellular Storage. ACS Chem Biol. 6(10): 1041-51.

ZhongM, Molday RS (2010). Binding of retinoids to ABCA4, thephotoreceptor ABC transporter associated with Stargardt macular degeneration.Methods Mol Biol. 652:163-76.

Molday RS, Zhong M,Quazi F (2009). The role of the photoreceptor ABC transporter ABCA4 in lipidtransport and Stargardt macular degeneration.

BiochimBiophys. Acta. 1791 (7): 573-83.

ZhongM, Molday LL, Molday RS (2009). Role of the C-terminus of thephotoreceptor ABCA4 transporter in the protein folding, function and retinaldegenerative diseases. J Biol Chem. 284 (6):3640-9.

MoldayRS, Beharry S, Ahn J, Zhong M (2006). Binding of N-retinylidene-PE toABCA4 and a model for its transport across membranes. Adv Exp Med Biol.572:465-70.

Beharry S, Zhong M,Molday RS (2004). N-retinylidene-phosphatidylethanolamine is thepreferred retinoid substrate for the photoreceptor-specific ABC transporterABCA4 (ABCR). J Biol Chem. 279 (52): 53972-9.