Temporal and Tissue Specific Regulation of RP-Associated Splicing Factor Genes PRPF3, PRPF31 and PRPC8—Implications in the Pathogenesis of RP

Genetic mutations in several ubiquitously expressed RNA splicing genes such as PRPF3, PRP31 and PRPC8, have been found to cause retina-specific diseases in humans. To understand this intriguing phenomenon, most studies have been focused on testing two major hypotheses. One hypothesis assumes that these mutations interrupt retina-specific interactions that are important for RNA splicing, implying that there are specific components in the retina interacting with these splicing factors. The second hypothesis suggests that these mutations have only a mild effect on the protein function and thus affect only the metabolically highly active cells such as retinal photoreceptors.We examined the second hypothesis using the PRPF3 gene as an example. We analyzed the spatial and temporal expression of the PRPF3 gene in mice and found that it is highly expressed in retinal cells relative to other tissues and its expression is developmentally regulated. In addition, we also found that PRP31 and PRPC8 as well as snRNAs are highly expressed in retinal cells.Our data suggest that the retina requires a relatively high level of RNA splicing activity for optimal tissue-specific physiological function. Because the RP18 mutation has neither a debilitating nor acute effect on protein function, we suggest that retinal degeneration is the accumulative effect of decades of suboptimal RNA splicing due to the mildly impaired protein

A clinical and molecular characterisation of CRB1-associated maculopathy

To date, over 150 disease-associated variants in CRB1 have been described, resulting in a range of retinal disease phenotypes including Leber congenital amaurosis and retinitis pigmentosa. Despite this, no genotype–phenotype correlations are currently recognised. We performed a retrospective review of electronic patient records to identify patients with macular dystrophy due to bi-allelic variants in CRB1. In total, seven unrelated individuals were identified. The median age at presentation was 21 years, with a median acuity of 0.55 decimalised Snellen units (IQR = 0.43). The follow-up period ranged from 0 to 19 years (median = 2.0 years), with a median final decimalised Snellen acuity of 0.65 (IQR = 0.70). Fundoscopy revealed only a subtly altered foveal reflex, which evolved into a bull’s-eye pattern of outer retinal atrophy. Optical coherence tomography identified structural changes—intraretinal cysts in the early stages of disease, and later outer retinal atrophy. Genetic testing revealed that one rare allele (c.498_506del, p.(Ile167_Gly169del)) was present in all patients, with one patient being homozygous for the variant and six being heterozygous. In trans with this, one variant recurred twice (p.(Cys896Ter)), while the four remaining alleles were each observed once (p.(Pro1381Thr), p.(Ser478ProfsTer24), p.(Cys195Phe) and p.(Arg764Cys)). These findings show that the rare CRB1 variant, c.498_506del, is strongly associated with localised retinal dysfunction. The clinical findings are much milder than those observed with bi-allelic, loss-of-function variants in CRB1, suggesting this in-frame deletion acts as a hypomorphic allele. This is the most prevalent disease-causing CRB1 variant identified in the non-Asian population to date

The CXC-Chemokine CXCL4 Interacts with Integrins Implicated in Angiogenesis

The human CXC-chemokine CXCL4 is a potent inhibitor of tumor-induced angiogenesis. Considering that CXCL4 is sequestered in platelet α-granules and released following platelet activation in the vicinity of vessel wall injury, we tested the hypothesis that CXCL4 might function as a ligand for integrins. Integrins are a family of adhesion receptors that play a crucial role in angiogenesis by regulating early angiogenic processes, such as endothelial cell adhesion and migration. Here, we show that CXCL4 interacts with αvβ3 on the surface of αvβ3-CHO. More importantly, human umbilical vein endothelial cells adhere to immobilized CXCL4 through αvβ3 integrin, and also through other integrins, such as αvβ5 and α5β1. We further demonstrate that CXCL4-integrin interaction is of functional significance in vitro, since immobilized CXCL4 supported endothelial cell spreading and migration in an integrin-dependent manner. Soluble CXCL4, in turn, inhibits integrin-dependent endothelial cell adhesion and migration. As a whole, our study identifies integrins as novel receptors for CXCL4 that may contribute to its antiangiogenic effect

Mutation Detection in Patients with Retinal Dystrophies Using Targeted Next Generation Sequencing

Retinal dystrophies (RD) constitute a group of blinding diseases that are characterized by clinical variability and pronounced genetic heterogeneity. The different nonsyndromic and syndromic forms of RD can be attributed to mutations in more than 200 genes. Consequently, next generation sequencing (NGS) technologies are among the most promising approaches to identify mutations in RD. We screened a large cohort of patients comprising 89 independent cases and families with various subforms of RD applying different NGS platforms. While mutation screening in 50 cases was performed using a RD gene capture panel, 47 cases were analyzed using whole exome sequencing. One family was analyzed using whole genome sequencing. A detection rate of 61% was achieved including mutations in 34 known and two novel RD genes. A total of 69 distinct mutations were identified, including 39 novel mutations. Notably, genetic findings in several families were not consistent with the initial clinical diagnosis. Clinical reassessment resulted in refinement of the clinical diagnosis in some of these families and confirmed the broad clinical spectrum associated with mutations in RD genes

Special Issue Introduction: Inherited Retinal Disease: Novel Candidate Genes, Genotype-Phenotype Correlations, and Inheritance Models

Inherited retinal diseases (IRDs) are genetically and clinically heterogeneous disorders.[...]

Presprouting effect on the yield of seed potatoes of new varieties under different soil and climate conditions

В период 1971-1980 гг. в опытных станциях Института картофелеводства, сельскохозяйственных академиях и воеводских центрах сельскохозяйственного прогресса проводились опыты с 21 сортом картофеля по влиянию предварительного проращивания на величину урожая, участие саженцев в урожае и коэффициент размножения. Результаты в общем числе 1300 для 21 сорта были классифицированы по отношению к сумме осадков в вегетационный период (июнь-август) и к механическому составу почвы (легкая и тяжелая супесь). Картофель возделывали на стойловом навозе при минеральном удобрении (80 кг N , 120 кг Р₂O₅ и 180 кг K₂O/ra в чистом элементе) в расстоянии 62,5 x 40 см. Дисперсионный анализ с регрессией для урожая клубней, участия саженцев в урожае и коэффициента размножения проводился на средних взвешенных значениях. Проведенные опыты показали существенное влияние предварительного проращивания на повышение общего урожая клубней и существенное снижение участия саженцев в урожае, Еоэффициент размножения был обусловлен видом почвы и количеством осадков. На более легких почвах как нехватка так и излишек осадков приводил к повышению участия саженцев в урожае и к росту коэффициента размножения. На более же тяжелых почвах самое высокое участие саженцев в урожае и самый высокий коэффициент размножения йыли установлены при наименьшей сумме осадков июня-августа (150 мм). Улучшение условий увлажнения приводило к снижению продукции саженцев.Experiments with 21 potato varieties concerning the pre-sprouting effect of the yield, share of seed potatoes in the yield and reproduction coefficient were carried out at Experiment Stations of the Institute for Potato Research, in Agricultural Universities and Districtal Centres of Agricultural Progress in the period 1971-1980. In total 1300 results for 21 varieties were classified with regard to the rainfall sum in the growing season (June-August) and mechanical composition of soil (light and heavy loamy sand). Potatoes were cultivated on farmyard manure and at the mineral fertilization (80 kg N, 120 kg P₂O₅ kg K₂ per hectare in pure element) at the spacing of 62.5 X 40.0 cm. The analysis of variance with the regression for the yield of tubers,share of seed potatoes in the yield and reproduction coefficient was performed for mean weighed values. The experiments have proved a significant pre-sprouting effect on the total tuber yield growth and a significant decrease of the share of seed potatoes in the yield. The reproduction coefficient depended on soil kind and rainfall amount. On lighter soils both deficiency and excess of rainfall led to a growth of the share of seed potatoes in the yield and to a growth of the reproduction coefficient value, whereas on heavier soils the highest share of seed potatoes in the yield and the highest reproduction coefficient value were found at the lowest rainfall sum of June-August (150 mm). An improvement of moisture conditions resulted in a decrease of the yield of seed potatoes

Effect of the soil and climate conditions on production of seed potatoes in 15 potato varieties

В настоящем труде использовали результаты разных опытов проведенных в 1971-1980 гг. в опытных станциях Института картофелеводства, воеводских центрах сельскохозяйственного прогресса и сольско-хозяйственных академиях с сортами Брыза, Ина, Янка, Кора, Краб, Леда, Ливия, Нарев, Нотець, Поля, Ронда, Рысь, Сокул, Сова и Тарпан. Результаты в общем числе 1960 были классифицированы по отношению к сумме осадков в месяцах июнь-август (ниже 150, 150-200, 200-250, 250-300, 300-350 и выше 350 мм), а также к виду почвы (средний песок, супесь, тяжелая супесь и более тяжелые почвы), равно как и по отношению к урожаю клубней, процентному участию саженцев в урожае и коэффициенту размножения. Картофель возделывали на стойловом новозе (ок. 25 т/га)при минеральном удобрении (80 кг N , 120 кг P₂O₅ и 180 кг K₅O) в расстоянии 62,5 х 40 см. Дисперсионный анализ с регрессией для урожая клубней, участия саженцев в урожае и коэффициента размножения проводился на средних взвешенных значениях. Вид почвы оказывал существенное влияние на урожаи картофеля - самые высокие урожаи получали на типично картофельных почвах. Зависимость между урожаем клубней и осадуами на легких почвах была линейного характера, тогда как на остальных почвах вак нехватна так и излишек осадков ограничивал урожай клубней. Участие саженцев в урожае и коэффициент репродукции зависели от вида почвы и количества осадков. Самая высокая продукция саженцев с гектара была получена на легких супесях в любых условиях увлажнения, на супесях при самых высоких осадках, на более тяжелых почвах при самых низких и самых высоких осадках, а на тяжелых супесях при самых низких осадках. Сорта разнились между собой величиной урожая, участием саженцев в урожае и коэффициентом репродукции. Ращличные почвенные и водные условия неодинаково влияли на сорта.Results of different experiments carried out in the period 1971-1980 by Experiment/Stations of the Institute for Potato Research, Districtal Centres of Agricultural Progress and Agricultural Universities with the Bryza, Ina, Janka, Kora, Krab, Leda, Liwia, Narew, Noteć, Pola, Ronda, Ryś, Sokół, Sowa and Tarpan varieties were made use of in the present work. In total 1960 varieties in relation to the rainfall sum in June-August (below 150, 150-200, 200-250, 250-300, 300-350 and over 350 mm) and the soil kinds (medium sand, loamy sand, heavy loamy sand and heavier soils) and in relation to the tuber yield, percentual share of seed potatoes in the yield and the reproduction coefficient were classified. Potatoes were cultivated on farmyard manure (about 25 t/ha) and at the mineral fertilization (80 kg N, 120 kg P₂O₅ 180 kg K₅O per hectare) in the spacing of 62,5x40,0 cm. The analysis of variance with the regression for the yield of tubers, share of seed potatoes in the yield and reproduction coefficient was performed on mean weighed values. The soil kind affected significantly the potato yields - the highest yields were obtained on typical potato soils. The relationship between the tuber yield and rainfalls on light soils was of linear character, while on remaining soils both deficiency and excess of rainfalls limited the yield of tubers. The share of seed potatoes in the yield and the reproduction coefficient depended on the soil kind and rainfall amount. The highest yield of seed potatoes from hectare was obtained on light loamy sands under any moisture conditions,on slightly loamy sands at the highest rainfall amounts, on heavier soils at lowest and highest rainfall amounts and on heavy loamy sands at the lowest rainfall amounts. The varieties differed with yield level, share of seed potatoes in the yield and reproduction coefficient value. Different soil and moisture conditions affected differently the given potato variety

Reevaluation of the Retinal Dystrophy Due to Recessive Alleles of RGR With the Discovery of a Cis-Acting Mutation in CDHR1

Purpose: Mutation of RGR, encoding retinal G-protein coupled receptor was originally reported in association with retinal dystrophy in 1999. A single convincing recessive variant segregated perfectly in one family of five affected and two unaffected siblings. At least one further individual, homozygous for the same variant has since been reported. The aim of this report was to reevaluate the findings in consideration of data from a whole genome sequencing (WGS) study of a large cohort of retinal dystrophy families. Methods: Whole genome sequencing was performed on 599 unrelated probands with inherited retinal disease. Detailed phenotyping was performed, including clinical evaluation, electroretinography, fundus photography, fundus autofluorescence imaging (FAF) and spectral-domain optical coherence tomography (OCT). Results: Overall we confirmed that affected individuals from six unrelated families were homozygous for both the reported RGR p.Ser66Arg variant and a nearby frameshifting deletion in CDHR1 (p.Ile841Serfs119*). All had generalized rod and cone dysfunction with severe macular involvement. An additional proband was heterozygous for the same CDHR1/RGR haplotype but also carried a second null CDHR1 mutation on a different haplotype. A comparison of the clinical presentation of the probands reported here with other CDHR1-related retinopathy patients shows the phenotypes to be similar in presentation, severity, and rod/cone involvement. Conclusions: These data suggest that the recessive retinal disorder previously reported to be due to homozygous mutation in RGR is, at least in part, due to variants in CDHR1 and that the true consequences of RGR knock-out on human retinal structure and function are yet to be determined