Two novel non-coding single nucleotide variants in the DNase1 hypersensitivity site of PRDM13 causing North Carolina macular dystrophy in Korea.

Purpose: Pathogenic variants in North Carolina macular dystrophy (NCMD) have rarely been reported in the East Asian population. Herein, we reported novel variants of NCMD in 2 Korean families. Methods: The regions associated with NCMD were analyzed with genome sequencing, and variants were filtered based on the minor allele frequency (0.5%) and heterozygosity. Non-coding variants were functionally annotated using multiple computational tools. Results: We identified two rare novel variants, chr6:g.99,598,914T>C (hg38; V17) and chr6:g.99,598,926G>A (hg38; V18) upstream of PRDM13 in families A and B, respectively. In Family 1, Grade 2 NCMD and a best-corrected visual acuity of 20/25 and 20/200 in the right and left eyes, respectively, were observed. In Family B, all affected individuals had Grade 1 NCMD with characteristic confluent drusen at the fovea and a best-corrected visual acuity of 20/20 in both eyes. These two variants are 10-22 bp downstream of the reported V10 variant within the DNase1 hypersensitivity site. This site is associated with progressive bifocal chorioretinal atrophy and congenital posterior polar chorioretinal hypertrophy and lies in the putative enhancer site of PRDM13. Conclusion: We identified two novel NCMD variants in the Korean population and further validated the regulatory role of the DNase1 hypersensitivity site upstream of PRDM13.

Whole genome sequencing for inherited retinal diseases in the Korean National Project of Bio Big Data.

PURPOSE: This study aimed to analyze the genetic results of inherited retinal diseases (IRDs) and evaluate the diagnostic usefulness of whole genome sequencing (WGS) in the Korean National Project of Bio Big Data. METHODS: As part of the Korean National Project of Bio Big Data, WGS was performed on 32 individuals with IRDs with no identified pathogenic variants through whole or targeted exome sequencing. RESULTS: Individuals with retinitis pigmentosa (n = 23), cone dystrophy (n = 2), cone-rod dystrophy (n = 2), familial exudative vitreoretinopathy (n = 2), pigmented paravenous chorioretinal atrophy (n = 1), North Carolina macular dystrophy (n = 1), and bull's-eye macular dystrophy (n = 1) were included. WGS revealed genetic mutations in the IQCB1, PRPF31, USH2A, and GUCY2D genes in five cases (15.6%). Two large structural variations and an intronic variant were newly detected in three cases. Two individuals had biallelic missense mutations that were not identified in previous exome sequencing. CONCLUSION: With WGS, the causative variants in 15.6% of unsolved IRDs from the Korean National Project of Bio Big Data were identified. Further research with a larger cohort might unveil the diagnostic usefulness of WGS in IRDs and other diseases.

ADDITIONAL PNEUMATIC RETINOPEXY IN PATIENTS WITH PERSISTENT RETINAL DETACHMENT AFTER SCLERAL BUCKLING.

PURPOSE: To investigate the efficacy, safety, and indications for additional pneumatic retinopexy (PR) in patients with persistent retinal detachment after scleral buckling. METHODS: This retrospective study included patients who underwent additional PR after scleral buckling for primary rhegmatogenous retinal detachment (n = 78). We defined "inadequate buckle" as retinal detachment persistence because of low buckle height despite accurate buckle placement and "buckle misplacement" as an uncovered tear because of incorrect buckle placement. RESULTS: The anatomical success rate after additional PR was 52.6%. Development of proliferative vitreoretinopathy Grade B (hazard ratio, 5.73; P < 0.001) and inferior retinal tears (hazard ratio, 2.12; P = 0.040) were significant risk factors for anatomical failure. The most common cause of anatomical failure was proliferative vitreoretinopathy (19 of 37; 51.4%), and epiretinal membrane formation was a common complication after additional PR (22 of 78; 28.2%). The anatomical success rate with additional PR was significantly higher in the inadequate buckle group than in the misplacement group (8 of 9 [88.9%] vs. 1228 [42.9%]; P = 0.023). CONCLUSION: Development of proliferative vitreoretinopathy Grade B and inferior retinal tears were significantly associated with anatomical failure after additional PR. Additional PR may benefit patients with superior retinal tears or low buckle height and those without proliferative vitreoretinopathy.

Phenotypic and Genetic Alterations in Adult-Onset Cone and Cone-Rod Dystrophy.

INTRODUCTION: The objective of this study was to investigate the clinical characteristics and genetic spectrum of adult-onset cone/cone-rod dystrophy (AOCD/AOCRD) in Korean individuals. METHODS: This is a single-center, retrospective cross-sectional study. We analyzed 22 individuals with genetically confirmed cone dystrophy, with symptoms beginning after 30 years of age. All patients underwent comprehensive ophthalmic and electrophysiological examinations. Exome sequencing of 296 genes associated with inherited retinal disease was performed. The clinical features of patients with AOCD/AOCRD and the causative genes and variants detected by exome sequencing were analyzed. RESULTS: The median age at the first visit was 52 years (range, 31-76 years), and the most common initial symptom was reduced visual acuity. In most cases, fundus photography showed a bull's eye pattern with foveal sparing, consistent with perifoveal photoreceptor loss on optical coherence tomography. We identified disease-causing variants in six genes: RP1, CRX, CDHR1, PROM1, CRB1, and GUCY2D. Pathogenic variants in RP1, CRX, and CDHR1 were identified in 77% of the AOCD/AOCRD cases, including p.Cys1399LeufsTer5, p.Arg1933Ter, and p.Ile2061SerfsTer12 in RP1; p.Ter300GlnextTer118 in CRX; and p.Glu201Lys in CDHR1. No characteristic imaging differences were observed for any of the causative genes. Most of the RP1-related AOCD/AOCRD cases showed a decreased amplitude only in the photopic electroretinogram (ERG), whereas CRX-related AOCD/AOCRD cases showed a slightly decreased amplitude in both the scotopic and photopic ERGs. CONCLUSION: In case of visual impairment with bull's eye pattern of RPE atrophy recognized after the middle age, a comprehensive ophthalmic examination and genetic test should be considered, with the possibility of AOCD/AOCRD in East Asians.

Bilateral macular hole in a patient with CAPN5-related neovascular inflammatory vitreoretinopathy.

PURPOSE: To characterize the genotype and phenotype of a patient with CAPN5-related neovascular inflammatory vitreoretinopathy (NIV) who have undergone surgery for macular holes. METHODS: We observed a patient presenting with retinitis pigmentosa and posterior uveitis who later developed vitreoretinal macular traction and a macular hole. Genetic testing was performed using a targeted gene panel. Fundus photography and spectral-domain optical coherence tomography were also performed. RESULTS: In a targeted gene panel, a monoallelic pathogenic variant, c.750G > T, p.Lys250Asn, in the CAPN5 gene was identified, and CAPN5-NIV was diagnosed. At the first visit, peripheral retinal degeneration and mild posterior uveitis were observed. At that time, neovascularization, epiretinal or fibrous membranes were not observed. After 5 years, vitreomacular traction developed and progressed to a full-thickness macular hole in both eyes. After pars plana vitrectomy, the macular hole was successfully closed without aggravation of uveitis. CONCLUSION: In this case, a pathogenic variant of CAPN5 lead to a distinct phenotype of retinitis pigmentosa, posterior uveitis, vitreomacular traction, and macular hole without typical inflammatory neovascularization or tractional membranes. Therefore, the clinical variability of CAPN5-NIV and genetic diagnosis should be considered in cases of atypical retinitis pigmentosa with bilateral macular hole.

Influence of Surgical Experience and Risk Factors for Surgical Failure in Primary Retinal Detachment Surgery.

INTRODUCTION: The aim of this study was to report surgical outcomes and risk factors for primary surgical failure following rhegmatogenous retinal detachment (RRD) repair. METHODS: In this retrospective cohort study, RRD patients who underwent primary surgery at a tertiary center between January 1, 2006, and December 31, 2020, were enrolled. Surgical failure was defined as reoperation within 60 days postoperatively due to retinal re-detachment and putative risk factors for surgical failure were analyzed. RESULTS: Of 2,383 eyes (2,335 patients), 1,342 (56.3%) underwent vitrectomy and 1,041 (43.7%) underwent scleral buckling. The surgical failure rate was 9.1% overall, and 6.0% and 13.1% for the vitrectomy and scleral buckling groups, respectively. In the multivariate logistic regression analysis, surgical failure was associated with surgical experience (first-year fellow vs. senior professor) (odds ratio [OR]: 1.66; p = 0.018), scleral buckling (OR: 2.33; p < 0.001), and longer axial length (AL; ≥26.5 mm) (OR: 1.49; p = 0.017). In each surgical approach, age <40 years (OR: 2.11; p = 0.029) in the vitrectomy group and age >40 years (OR, 1.84; p = 0.004), male sex (OR: 1.65; p = 0.015), and first-year fellows compared to senior professors (OR: 1.95; p = 0.013) in the scleral buckling group were associated with surgical failure. Lens status were not associated with the surgical failure rate. CONCLUSION: In this large retrospective study using data from Korea, vitrectomy was superior to scleral buckling in terms of primary anatomical outcomes in the management of RRD. First-year fellows were a risk factor for surgical failure, especially for scleral buckling. Longer AL was a significant parameter for predicting the success rates.

Short-Term Safety and Efficacy of Intravitreal Brolucizumab Injections for Neovascular Age-Related Macular Degeneration: A Multicenter Retrospective Real-World Study.

INTRODUCTION: The aim of the study was to determine the short-term real-world safety and efficacy of intravitreal brolucizumab injections in Korean patients with neovascular age-related macular degeneration (nAMD). METHODS: This multicenter retrospective study involved 294 eyes (treatment naïve 20 eye [6.8%] and nontreatment naïve 274 eyes [93.2%]) of 290 patients from 13 hospitals or retinal centers in South Korea. Patients with nAMD who received brolucizumab injection(s) between April 1 and November 30, 2021, with a follow-up ≥1 month, were included. Primary outcomes were safety, incidence of intraocular inflammation (IOI), and potential risk factors. The secondary outcome was efficacy, i.e., change in best-corrected visual acuity (BCVA) and optical coherence tomography-measured macular thickness and retinal fluid. RESULTS: The mean age was 71.63 ± 8.66. The follow-up period was 2.38 ± 0.79 months. The mean number of brolucizumab injections during the follow-up was 1.52 ± 0.58. The overall incidence of IOI was 13.9% (n = 41 eyes). Most IOI cases were of anterior uveitis (8.8%, 26 eyes), followed by retinal vasculitis (2.4%, seven eyes) and occlusive retinal vasculitis (0.3%, one eye). Most eyes showed IOI resolution (n = 40, 97.5%) and BCVA restoration (n = 39, 95.1%) with or without corticosteroid treatment during the follow-up. Age, sex, IOI history, or other anti-vascular endothelial growth factor injection histories were not associated with the occurrence of IOI. However, only thin subfoveal choroidal thickness (SFCT) was associated with the occurrence of IOI (odds ratio = 0.995, p = 0.020). BCVA at 1 month improved from baseline (baseline 0.518 ± 0.356 vs. 1 month 0.503 ± 0.383, p = 0.023), but the improvement was not maintained. Anatomical improvement was significant after 3 months. CONCLUSION: In Korean patients with nAMD, the incidence of IOI following brolucizumab injections was 13.9%. IOI was well-controlled with or without steroid treatment. Most IOI eyes (95.1%) were restored to the level of vision before. IOI occurrence and occlusive vasculitis was rare. In the short term, brolucizumab injection effectively improved vision at 1 month and dried retinal fluid for 3 months.

Broad locations of antigenic regions for anti-TRPM1 autoantibodies in paraneoplastic retinopathy with retinal ON bipolar cell dysfunction.

PURPOSE: Cancer-associated retinal ON bipolar cell dysfunction (CARBD), which includes melanoma-associated retinopathy (MAR), has been reported to be caused by autoantibodies against the molecules expressed in ON bipolar cells, including TRPM1. The purpose of this study was to determine the antigenic regions of the autoantibodies against TRPM1 in the sera of CARBD patients, in whom we previously detected anti-TRPM1 autoantibodies. METHODS: The antigenic regions against TRPM1 in the sera of eight CARBD patients were examined by Western blots using HEK293T cells transfected with the plasmids expressing FLAG-tagged TRPM1 fragments. The clinical course of these patients was also documented. RESULTS: The clinical course differed among the patients. The electroretinograms (ERGs) and symptoms were improved in three patients, deteriorated in one patient, remained unchanged for a long time in one patient, and were not followable in three patients. Seven of the eight sera possessed multiple antigenic regions: two sera contained at least four antigen recognition regions, and three sera had at least three regions. The antigen regions were spread over the entire TRPM1 protein: five sera in the N-terminal intracellular domain, six sera in the transmembrane-containing region, and six sera in the C-terminal intracellular domain. No significant relationship was observed between the location of the antigen epitope and the patients' clinical course. CONCLUSIONS: The antigenic regions of anti-TRPM1 autoantibodies in CARBD patients were present not only in the N-terminal intracellular domain, which was reported in an earlier report, but also in the transmembrane-containing region and in the C-terminal intracellular domain. In addition, the antigenic regions for TRPM1 were found to vary among the CARBD patients examined, and most of the sera had multiple antigenic regions.

EPIRETINAL MEMBRANE SURGERY IN PATIENTS WITH MULTIFOCAL VERSUS MONOFOCAL INTRAOCULAR LENSES.

PURPOSE: To compare the visual/anatomical outcomes and feasibility of epiretinal membrane surgery between patients with multifocal or monofocal intraocular lenses (IOLs). METHODS: We reviewed the medical records of 46 patients who underwent epiretinal membrane surgery under multifocal or monofocal IOL pseudophakia. The operation time, mean changes in best-corrected visual acuity, and central macular thickness, and complications were compared between the groups. RESULTS: Macular surgery was performed in 22 and 24 eyes with multifocal and monofocal IOLs, respectively. The total operation time and the total membrane peeling time were similar in both groups (P = 0.125, P = 0.462, respectively). The mean time to create a membrane edge or flap with retinal microforceps was longer for multifocal than for monofocal IOLs (P = 0.013). The mean changes in best-corrected visual acuity and central macular thickness were similar in both groups (P = 0.682, P = 0.741, respectively). Complications were similar between groups. CONCLUSION: With multifocal IOLs, vision outside the central surgical field was blurred, requiring more time to create the membrane flap. Retinal surgeons should anticipate the difficulty in precise focusing when creating a membrane flap in macular surgery in patients with multifocal IOLs and should pay more attention to the macular surgery.

Extraciliary roles of the ciliopathy protein JBTS17 in mitosis and neurogenesis.

OBJECTIVE: JBTS17 is a major gene mutated in ciliopathies such as Joubert syndrome and oral-facial-digital syndrome type VI. Most patients with loss of function mutations in JBTS17 exhibit cerebellar vermis hypoplasia and brainstem malformation. However, some patients with JBTS17 mutations show microcephaly and abnormal gyration. We examined potential roles of JBTS17 in neurogenesis to understand the pathological mechanism of JBTS17-related cortical abnormalities. METHODS: We examined subcellular localization and cell-cycle-dependent expression of JBTS17 proteins using anti-JBTS17 antibodies and JBTS17 expression vectors. We also performed knockdown experiments to determined roles of JBTS17 in human cells, and demonstrated mitotic functions of JBTS17 using immunostaining and live imaging. We examined the involvement of JBTS17 in cortical neurogenesis using a mouse in utero electroporation technique. RESULTS: We found that JBTS17 localizes to the kinetochore and the level of JBTS17 is regulated by cell-cycle-dependent proteolysis. Depletion of JBTS17 disrupts chromosome alignment and spindle pole orientation, resulting in mitotic delay. JBTS17 interacts with LIS1 and influences LIS1 localization. Depletion of Jbts17 in the developing mouse cortex interferes with the mitotic progression of neural progenitors and the migration of postmitotic neurons. INTERPRETATION: LIS1 is implicated in lissencephaly, but altered dosage of LIS1 has been also associated with microcephaly syndromes. Our results suggest that JBTS17 contributes to mitotic progression by interacting with LIS1, and abnormal mitosis is an underlying mechanism of the microcephaly phenotype in JBTS17-related ciliopathies. We propose that understanding extraciliary roles of ciliopathy proteins is important to elucidate pathological mechanisms underlying diverse ciliopathy phenotypes. ANN NEUROL 2019.

A case of melanoma-associated retinopathy with autoantibodies against TRPM1.

PURPOSE: To report a case of melanoma-associated retinopathy (MAR) with autoantibodies against the transient receptor potential cation channel, subfamily M, member 1 (TRPM1) with asymmetric severe vision loss. METHODS: We evaluated a patient with heel skin melanoma showing progressive vision loss in both eyes confirmed with a baseline ophthalmic examination, fluorescein angiography, spectral domain optical coherence tomography (OCT), visual field test, and full-field electroretinogram (ERG). Immunofluorescence assays and western blot analysis revealed autoantibodies in the patient's serum. RESULTS: The patient's best-corrected visual acuities were 20/50 in the right eye and hand motion in the left eye. Visual field test showed severely depressed visual fields especially in the left eye. Fluorescein angiography and OCT revealed extrafoveal choroidal neovascularization in the left eye. The patient had an electronegative ERG, suggesting MAR, and autoantibodies against TRPM1 and aldolase C were detected in the patient's blood sample. CONCLUSIONS: The clinical features of MAR patients with positive anti-TRPM1 autoantibodies can be manifested as severe vision loss, and the identification of autoantibodies can be helpful for confirming the diagnosis.

Genotypic profile and phenotype correlations of ABCA4-associated retinopathy in Koreans.

Purpose: This study was conducted to analyze the clinical features associated with the pathogenic variants of ABCA4 in Korean patients with inherited retinal dystrophies (IRDs). Methods: We enrolled patients with IRDs who visited a tertiary referral hospital and identified the pathogenic variants of ABCA4 through targeted gene panel sequencing and whole exome sequencing. We analyzed the clinical characteristics and phenotypic spectrum according to genotype. Results: Eleven patients (from nine families) with IRDs and pathogenic variants in ABCA4 were included. Eight patients (from seven families) with Stargardt disease (STGD), two (from one family) with cone-rod dystrophy (CRD), and one with early-onset retinitis pigmentosa (RP) were included. Two heterozygous mutations were identified in eight families, and one variant was found in a patient with fundus flavimaculatus. Two variants, p.Gln294Ter and p.Gln636Lys, were associated with severe phenotypes, such as early-onset RP and CRD. Four novel pathogenic variants, p.Gln636Lys, p.Ile1114del, p.Thr1117Ala, and p.Asn1588Tyr, were identified. p.Gln294Ter, p.Leu1157Ter, and p.Lys2049ArgfsTer12 were repeatedly detected in Koreans with ABCA4-associated retinal diseases (ABCA4-RD). Conclusions: Various pathogenic variants of ABCA4, including four novel variants, were identified, and ABCA4-RD exhibited various phenotypes and disease severities in a Korean IRD cohort. These findings will be useful for understanding the clinical features of ABCA4-RD and ethnicity-specific variants in East Asians.

Clinical and Genetic Characteristics of East Asian Patients with Occult Macular Dystrophy (Miyake Disease): East Asia Occult Macular Dystrophy Studies Report Number 1.

PURPOSE: To describe the clinical and genetic characteristics of the cohort enrolled in the East Asian studies of occult macular dystrophy (OMD). DESIGN: International, multicenter, retrospective cohort studies. PARTICIPANTS: A total of 36 participants from 21 families with a clinical diagnosis of OMD and harboring pathogenic RP1L1 variants (i.e., Miyake disease) were enrolled from 3 centers in Japan, China, and South Korea. METHODS: A detailed history was obtained, and comprehensive ophthalmological examinations including spectral-domain OCT were performed. All detected sequence variants in the RP1L1 gene were reviewed, and in silico analysis was performed, including allele frequency analyses and pathogenicity predictions. MAIN OUTCOME MEASURES: Onset of disease, visual acuity (VA) converted to the logarithm of the minimum angle of resolution (logMAR), OCT findings, and effect of detected variants. RESULTS: Eleven families from Japan, 6 from South Korea, and 4 from China were recruited. There were 12 female and 24 male participants. The median age of onset was 25.5 years (range, 2-73), and the median age at the latest examination was 46.0 years (range, 11-86). The median VA (logMAR) was 0.65 (range, -0.08-1.22) in the right eye and 0.65 (-0.08-1.10) in the left eye. A significant correlation between onset of disease and VA was revealed. The Classical morphologic phenotype showing both blurred ellipsoid zone and absence of interdigitation zone of the photoreceptors was demonstrated in 30 patients (83.3%), and subtle photoreceptor architectural changes were demonstrated in 6 patients (16.6%). Eight pathogenic RP1L1 variants were identified, including 6 reported variants and 1 novel variant: p.R45W, p.T1194M/p.T1196I (complex), p.S1199C, p.G1200A, p.G1200D, p.V1201G, and p.S1198F, respectively. Two variants were recurrent: p.R45W (11 families, 52.4%) and p.S1199C (5 families, 23.8%). The pathogenic missense variants in 10 families (47.6%) were located within the previously reported unique motif, including 6 amino acids (1196-1201). CONCLUSIONS: There is a large spectrum of clinical findings in Miyake disease, including various onset of disease and VA, whereas the characteristic photoreceptor microstructures were shared in most cases. Two hot spots including amino acid numbers 45 and 1196-1201 in the RP1L1 gene were confirmed in the East Asian population.

Export of membrane proteins from the Golgi complex to the primary cilium requires the kinesin motor, KIFC1.

Microtubule-based motors contribute to the efficiency and selectivity of Golgi exit and post-Golgi transport of membrane proteins that are targeted to distinct compartments. Cytoplasmic dynein moves post-Golgi vesicles that carry rhodopsin toward the base of the connecting cilium in photoreceptor cells; however, the identity of the motors that are involved in the vesicular trafficking of ciliary membrane proteins in nonphotoreceptor cells remains unclear. Here, we demonstrate that the minus end-directed kinesin KIFC1 (kinesin family member C1) is required for both ciliary membrane protein transport and serum starvation-induced ciliogenesis in retinal pigmented epithelial 1 cells. Although KIFC1 is known as a mitotic motor that is sequestered in the nucleus during interphase, KIFC1 immunoreactivity appeared in the Golgi region after serum starvation. Knockdown of KIFC1 inhibited the export of ciliary receptors from the Golgi complex. KIFC1 overexpression affected the Golgi localization of GMAP210 (Golgi microtubule-associated protein 210) and IFT20 (intraflagellar transport 20), which are involved in membrane protein transport to cilia. Moreover, KIFC1 physically interacted with ASAP1 (ADP-ribosylation factor GTPase-activating protein with SH3 domain, ankyrin repeat and PH domain 1), which regulates the budding of rhodopsin transport carriers from the Golgi complex, and KIFC1 depletion caused Golgi accumulation of ASAP1. A decrease in the centrosomal levels of IFT20 and TTBK2 (τ-tubulin kinase 2) was associated with ciliogenesis defects in KIFC1-depleted cells. Our results suggest that KIFC1 plays roles in the Golgi exit of ciliary receptors and in the recruitment of ciliogenesis regulators.-Lee, S.-H., Joo, K., Jung, E. J., Hong, H., Seo, J., Kim, J. Export of membrane proteins from the Golgi complex to the primary cilium requires the kinesin motor, KIFC1.

Erratum: Correction of Table: Genetic Mutation Profiles in Korean Patients with Inherited Retinal Diseases.

This corrects the article on e161 in vol. 34, PMID: 31144483.

Genetic Mutation Profiles in Korean Patients with Inherited Retinal Diseases.

BACKGROUND: Because of genetically and phenotypically heterogenous features, identification of causative genes for inherited retinal diseases (IRD) is essential for diagnosis and treatment in coming gene therapy era. To date, there are no large-scale data of the genes responsible for IRD in Korea. The aim of this study was to identify the distribution of genetic defects in IRD patients in Korea. METHODS: Medical records and DNA samples from 86 clinically diagnosed IRD patients were consecutively collected between July 2011 and May 2015. We applied the next-generation sequencing strategy (gene panel) for screening 204 known pathogenic genes associated with IRD. RESULTS: Molecular diagnoses were made in 38/86 (44.2%) IRD patients: 18/44 (40.9%) retinitis pigmentosa (RP), 8/22 (36.4%) cone dystrophy, 6/7 (85.7%) Stargardt disease, 1/1 (100%) Best disease, 1/1 (100%) Bardet-Biedl syndrome, 1/1 (100%) congenital stationary night blindness, 1/1 (100%) choroideremia, and 2/8 (25%) other macular dystrophies. ABCA4 was the most common causative gene associated with IRD and was responsible for causing Stargardt disease (n = 6), RP (n = 1), and cone dystrophy (n = 1). In particular, mutations in EYS were found in 4 of 14 autosomal recessive RP (29%). All cases of Stargardt disease had a mutation in the ABCA4 gene with an autosomal recessive trait. CONCLUSION: This study provided the distribution of genetic mutations responsible for causing IRD in the Korean patients. This data will serve as a reference for future genetic screening and treatment for Korean IRD patients.

Ribonuclease 5 coordinates signals for the regulation of intraocular pressure and inhibits neural apoptosis as a novel multi-functional anti-glaucomatous strategy.

Glaucoma is a vision-threatening disorder characterized by progressive death of retinal ganglion cells (RGCs), although little is known about therapeutic milestones. Due to its complex and multifactorial pathogenesis, multipronged therapeutic approach is needed. Angiogenin (ANG), now called ribonuclease (RNase) 5, has been previously known as angiogenic factor and more recently its biologic activity is extended to promoting cell survival via its ribonucleolytic activity. Here, we revealed the defect of ANG in human glaucomatous trabecular meshwork (TM) cells and identified novel multiple functions of ANG as an anti-glaucomatous strategy. ANG was highly expressed in normal eyes and normal TM cells compared to glaucomatous TM cells. ANG induced intraocular pressure (IOP) lowering in rat models of both normal and elevated IOP, and as a possible mechanism, activated Akt-mediated signals for nitric oxide (NO) production, an important regulator of IOP in glaucomatous TM cell. Moreover, we demonstrated ANG-induced production of matrix metalloproteinase (MMP)-1 and -3 and rho-kinase inhibition for TM remodeling. For anti-glaucomatous defense optimization, ANG not only elicited immune-modulative pathways via indolamine 2,3-dioxygenase (IDO) activation in TM cells and suppression of Jurkat T cells, but also rescued neural stem cells (NSCs) from apoptosis induced by glaucomatous stress. These results demonstrate that novel multi-functional effects of ANG may have benefits against glaucoma in ocular tissues.

Mutations of CEP83 cause infantile nephronophthisis and intellectual disability.

Ciliopathies are a group of hereditary disorders associated with defects in cilia structure and function. The distal appendages (DAPs) of centrioles are involved in the docking and anchoring of the mother centriole to the cellular membrane during ciliogenesis. The molecular composition of DAPs was recently elucidated and mutations in two genes encoding DAPs components (CEP164/NPHP15, SCLT1) have been associated with human ciliopathies, namely nephronophthisis and orofaciodigital syndrome. To identify additional DAP components defective in ciliopathies, we independently performed targeted exon sequencing of 1,221 genes associated with cilia and 5 known DAP protein-encoding genes in 1,255 individuals with a nephronophthisis-related ciliopathy. We thereby detected biallelic mutations in a key component of DAP-encoding gene, CEP83, in seven families. All affected individuals had early-onset nephronophthisis and four out of eight displayed learning disability and/or hydrocephalus. Fibroblasts and tubular renal cells from affected individuals showed an altered DAP composition and ciliary defects. In summary, we have identified mutations in CEP83, another DAP-component-encoding gene, as a cause of infantile nephronophthisis associated with central nervous system abnormalities in half of the individuals.

Angiogenin ameliorates corneal opacity and neovascularization via regulating immune response in corneal fibroblasts.

BACKGROUND: Angiogenin (ANG), a component of tears, is involved in the innate immune system and is related with inflammatory disease. We investigated whether ANG has an immune modulatory function in human corneal fibroblasts (HCFs). METHODS: HCFs were cultured from excised corneal tissues. The gene or protein expression levels of interleukin (IL)-1beta (ß), IL-4, IL-6, IL-8, IL-10, complements, toll-like receptor (TLR)4, myeloid differentiation primary response gene (MYD)88, TANK-binding kinase (TBK)1, IkappaB kinase-epsilon (IKK-ε) and nuclear factor-kappaB (NF-κB) were analyzed with or without ANG treatment in tumor necrosis factor-alpha (TNF-α)- or lipopolysaccharide (LPS)-induced inflammatory HCFs by real-time polymerase chain reaction (PCR), Western blotting and immunocytochemistry. Inflammatory cytokine profiles with or without ANG were evaluated through immunodot blot analysis in inflammatory HCFs. Corneal neovascularization and opacity in a rat model of corneal alkali burn were evaluated after application of ANG eye drops. RESULTS: ANG decreased the mRNA levels of IL-1ß, IL-6, IL-8, TNF-α receptor (TNFR)1, 2, TLR4, MYD88, and complement components except for C1r and C1s and elevated the mRNA expression of IL-4 and IL-10. Increased signal intensity of IL-6, IL-8 and monocyte chemotactic protein (MCP)-1 and MCP-2 induced by TNF-α or LPS was weakened by ANG treatment. ANG reduced the protein levels of IKK-ε by either TNF-α and LPS, and decreased TBK1 production induced by TNF-α, but not induced by LPS. The expression of NF-κB in the nuclei was decreased after ANG treatment. ANG application lowered corneal neovascularization and opacity in rats compared to controls. CONCLUSION: These results demonstrate that ANG reduces the inflammatory response induced by TNF-α or LPS in HCFs through common suppression of IKK-ε-mediated activation of NF-κB. This may support the targeting of immune-mediated corneal inflammation by using ANG.

CCDC41 is required for ciliary vesicle docking to the mother centriole.

The initiation of primary cilium assembly entails the docking of ciliary vesicles presumably derived from the Golgi complex to the distal end of the mother centriole. Distal appendages, which anchor the mother centriole to the plasma membrane, are thought to be involved in the docking process. However, little is known about the molecular players and mechanisms that mediate the vesicle-centriole association. Here we report that coiled-coil domain containing 41 (CCDC41) is required for the docking of ciliary vesicles. CCDC41 specifically localizes to the distal end of the mother centriole and interacts with centrosomal protein 164 (Cep164), a distal appendage component. In addition, a pool of CCDC41 colocalizes with intraflagellar transport protein 20 (IFT20) subunit of the intraflagellar transport particle at the Golgi complex. Remarkably, knockdown of CCDC41 inhibits the recruitment of IFT20 to the centrosome. Moreover, depletion of CCDC41 or IFT20 inhibits ciliogenesis at the ciliary vesicle docking step, whereas intraflagellar transport protein 88 (IFT88) depletion interferes with later cilium elongation steps. Our results suggest that CCDC41 collaborates with IFT20 to support the vesicle-centriole association at the onset of ciliogenesis.