@article {2051, title = {Cilia-associated wound repair mediated by IFT88 in retinal pigment epithelium.}, journal = {Sci Rep}, volume = {13}, year = {2023}, month = {2023 May 21}, pages = {8205}, abstract = {

Primary cilia are conserved organelles that integrate extracellular cues into intracellular signals and are critical for diverse processes, including cellular development and repair responses. Deficits in ciliary function cause multisystemic human diseases known as ciliopathies. In the eye, atrophy of the retinal pigment epithelium (RPE) is a common feature of many ciliopathies. However, the roles of RPE cilia in vivo remain poorly understood. In this study, we first found that mouse RPE cells only transiently form primary cilia. We then examined the RPE in the mouse model of Bardet-Biedl Syndrome 4 (BBS4), a ciliopathy associated with retinal degeneration in humans, and found that ciliation in BBS4 mutant RPE cells is disrupted early during development. Next, using a laser-induced injury model in vivo, we found that primary cilia in RPE reassemble in response to laser injury during RPE wound healing and then rapidly disassemble after the repair is completed. Finally, we demonstrated that RPE-specific depletion of primary cilia in a conditional mouse model of cilia loss promoted wound healing and enhanced cell proliferation. In summary, our data suggest that RPE cilia contribute to both retinal development and repair and provide insights into potential therapeutic targets for more common RPE degenerative diseases.

}, keywords = {Animals, Cilia, Ciliopathies, Disease Models, Animal, Humans, Mice, Microtubule-Associated Proteins, Retinal Degeneration, Retinal Pigment Epithelium, Tumor Suppressor Proteins}, issn = {2045-2322}, doi = {10.1038/s41598-023-35099-3}, author = {Ning, Ke and Bhuckory, Mohajeet B and Lo, Chien-Hui and Sendayen, Brent E and Kowal, Tia J and Chen, Ming and Bansal, Ruchi and Chang, Kun-Che and Vollrath, Douglas and Berbari, Nicolas F and Mahajan, Vinit B and Hu, Yang and Sun, Yang} } @article {659, title = {BESTROPHIN1 mutations cause defective chloride conductance in patient stem cell-derived RPE.}, journal = {Hum Mol Genet}, volume = {25}, year = {2016}, month = {2016 07 01}, pages = {2672-2680}, abstract = {

Bestrophin1 (BEST1) is expressed in human retinal pigment epithelium (RPE) and mutations in the BEST1 gene commonly cause retinal dysfunction and macular degeneration. BEST1 is presumed to assemble into a calcium-activated chloride channel and be involved in chloride transport but there is no direct evidence in live human RPE cells to support this idea. To test whether BEST1 functions as a chloride channel in living tissue, BEST1-mutant RPE (R218H, L234P, A243T) were generated from patient-derived induced pluripotent stem cells and compared with wild-type RPE in a retinal environment, using a biosensor that visualizes calcium-induced chloride ion flux in the cell. Calcium stimulation elicited chloride ion export in normal RPE but not in RPE derived from three patients with BEST1 mutations. These data, along with three-dimensional modeling, provide evidence that BEST1 assembles into a key calcium-sensing chloride channel in human RPE.

}, keywords = {Bestrophins, Calcium Signaling, Chloride Channels, Chlorides, Eye Proteins, Humans, Induced Pluripotent Stem Cells, Mutation, Retinal Pigment Epithelium, Vitelliform Macular Dystrophy}, issn = {1460-2083}, doi = {10.1093/hmg/ddw126}, author = {Moshfegh, Yasmin and Velez, Gabriel and Li, Yao and Bassuk, Alexander G and Mahajan, Vinit B and Tsang, Stephen H} } @article {719, title = {Proteomic landscape of the human choroid-retinal pigment epithelial complex.}, journal = {JAMA Ophthalmol}, volume = {132}, year = {2014}, month = {2014 Nov}, pages = {1271-81}, abstract = {

IMPORTANCE: Differences in geographical protein expression in the human choroid-retinal pigment epithelial (RPE) complex may explain molecular predisposition of regions to ophthalmic diseases such as age-related macular degeneration.

OBJECTIVE: To characterize the proteome of the human choroid-RPE complex and to identify differentially expressed proteins in specific anatomic regions.

DESIGN, SETTING, AND PARTICIPANTS: Experimental study of choroid-RPE tissue from 3 nondiseased eyes. The choroid-RPE complex underwent biopsy from beneath the foveal, macular, and peripheral retina. Protein fractions were isolated and subjected to multidimensional liquid chromatography and tandem mass spectrometry. A bioinformatic pipeline matched peptide spectra to the human proteome, assigned gene ontology classification, and identified protein signaling pathways unique to each of the choroid-RPE regions.

MAIN OUTCOMES AND MEASURES: Mean number of mass spectra, statistically significant differentially expressed proteins, gene ontology classification, and pathway representation.

RESULTS: We identified a mean of 4403 unique proteins in each of the foveal, macular, and peripheral choroid-RPE tissues. Six hundred seventy-one differentially expressed proteins included previously known risk factors for retinal diseases related to oxidative stress, inflammation, and the complement cascade. Gene ontology analysis showed that unique categories in the foveal and macular regions included immune process proteins as well as protein complexes and plasma membrane proteins. The peripheral region contained unique antioxidant activity proteins. Many proteins had the highest expression in the foveal or macular regions, including inflammation-related proteins HLA-A, HLA-B, and HLA-C antigens; intercellular adhesion molecule 1 (ICAM-1); S100; transcription factor ERG; antioxidant superoxide dismutase 1 (SOD1); chloride intracellular channel 6 ion (CLIC6); activators of the complement cascade C1q, C6, and C8; and complement factor H. Proteins with higher expression in the periphery included bestrophin 1 (BEST1), transcription factor RNA binding motif protein 39 (RBM39), inflammatory mediator macrophage migration inhibitory factor, antioxidant SOD3, ion channel voltage-dependent anion-selective channel protein 3 (VDAC3), and complement inhibitor CD55. The complement activation was among the highest represented pathways (P < 7.5e-13).

CONCLUSIONS AND RELEVANCE: This proteomic data set identifies novel molecular signatures in anatomically sensitive regions of the choroid-RPE complex. The findings give mechanistic insight into choroid-RPE function, reveal important choroid-RPE processes, and prioritize new pathways for therapeutic targeting.

}, keywords = {Aged, 80 and over, Choroid, Chromatography, Liquid, Computational Biology, Eye Proteins, Female, Gene Expression Regulation, Gene Ontology, Humans, Male, Proteome, Proteomics, Retinal Pigment Epithelium, Tandem Mass Spectrometry}, issn = {2168-6173}, doi = {10.1001/jamaophthalmol.2014.2065}, author = {Skeie, Jessica M and Mahajan, Vinit B} } @article {173, title = {A new macular dystrophy with anomalous vascular development, pigment spots, cystic spaces, and neovascularization.}, journal = {Archives of ophthalmology}, volume = {127}, year = {2009}, month = {2009 Nov}, pages = {1449-57}, abstract = {

To clinically phenotype an inherited macular dystrophy with peculiar intraretinal pigment spots, cysts, and hemorrhage in a 24-year-old female proband and her family.

}, keywords = {Adolescent, Adult, Amblyopia, Child, Child, Preschool, Cysts, Electroretinography, Female, Fluorescein Angiography, Humans, Macular Degeneration, Male, Middle Aged, Pedigree, Phenotype, Retinal Hemorrhage, Retinal Neovascularization, Retinal Pigment Epithelium, Retinal Vessels, Strabismus, Tomography, Optical Coherence, Visual Acuity, Young Adult}, author = {Mahajan, Vinit B and Russell, Stephen R and Stone, Edwin M} }