The Microphthalmia-associated Transcription Factor (MITF) governs numerous cellular and developmental processes. In mice, it promotes specification and differentiation of the retinal pigmented epithelium (RPE), and in humans, some mutations in MITF induce congenital eye malformations. Herein, we explore the function and regulation of Mitf in Drosophila eye development and uncover two roles. We find that knockdown of Mitf results in retinal displacement (RDis), a phenotype associated with abnormal eye formation. Mitf functions in the peripodial epithelium (PE), a retinal support tissue akin to the RPE, to suppress RDis, via the Hippo pathway effector Yorkie (Yki). Yki physically interacts with Mitf and can modify its transcriptional activity in vitro. Severe loss of Mitf, instead, results in the de-repression of retinogenesis in the PE, precluding its development. This activity of Mitf requires the protein phosphatase 2 A holoenzyme STRIPAK-PP2A, but not Yki; Mitf transcriptional activity is potentiated by STRIPAK-PP2A in vitro and in vivo. Knockdown of STRIPAK-PP2A results in cytoplasmic retention of Mitf in vivo and in its decreased stability in vitro, highlighting two potential mechanisms for the control of Mitf function by STRIPAK-PP2A. Thus, Mitf functions in a context-dependent manner as a key determinant of form and fate in the Drosophila eye progenitor epithelium.

UNASSIGNED: Multiple large-scale genome-wide association meta-analyses studies have reliably identified an association between genetic variants within the SHROOM3 gene and chronic kidney disease. This association extends to alterations in known markers of kidney disease including baseline estimated glomerular filtration rate, urinary albumin-to-creatinine ratio, and blood urea nitrogen. Yet, an understanding of the molecular mechanisms behind the association of SHROOM3 and kidney disease remains poorly communicated. We conducted a narrative review to summarize the current state of literature regarding the genetic and molecular relationships between SHROOM3 and kidney development and disease.
UNASSIGNED: PubMed, PubMed Central, SCOPUS, and Web of Science databases, as well as review of references from relevant studies and independent Google Scholar searches to fill gaps in knowledge.
UNASSIGNED: A comprehensive narrative review was conducted to explore the molecular mechanisms underlying SHROOM3 and kidney development, function, and disease.
UNASSIGNED: SHROOM3 is a unique protein, as it is the only member of the SHROOM group of proteins that regulates actin dynamics through apical constriction and apicobasal cell elongation. It holds a dichotomous role in the kidney, as subtle alterations in SHROOM3 expression and function can be both pathological and protective toward kidney disease. Genome-wide association studies have identified genetic variants near the transcription start site of the SHROOM3 gene associated with chronic kidney disease. SHROOM3 also appears to protect the glomerular structure and function in conditions such as focal segmental glomerulosclerosis. However, little is known about the exact mechanisms by which this protection occurs, which is why SHROOM3 binding partners remain an opportunity for further investigation.
UNASSIGNED: Our search was limited to English articles. No structured assessment of study quality was performed, and selection bias of included articles may have occurred. As we discuss future directions and opportunities, this narrative review reflects the academic views of the authors.
UNASSIGNED: Plusieurs méta-analyses d’envergure portant sur des études d’association pangénomiques ont permis d’identifier de manière fiable une association entre des variants génétiques du gène SHROOM3 et l’insuffisance rénale chronique. Cette association s’étend aux altérations des marqueurs connus de l’insuffisance rénale, notamment le débit de filtration glomérulaire estimé initial, le rapport albumine/créatinine urinaire et le taux d’urée dans le sang. Pourtant, la compréhension des mécanismes moléculaires qui sous-tendent cette association entre SHROOM3 et l’insuffisance rénale reste mal communiquée. Nous avons procédé à une revue narrative afin de résumer l’état actuel de la littérature en ce qui concerne les relations génétiques et moléculaires entre SHROOM3 et le développement des reins et de l’insuffisance rénale.
UNASSIGNED: Les bases de données PubMed, PubMed Central, SCOPUS et Web of Science. L’examen des références des études pertinentes et des recherches indépendantes sur Google Scholar a également été réalisé pour combler les lacunes dans les connaissances.
UNASSIGNED: Une revue narrative complète a été effectuée afin d’explorer les mécanismes moléculaires qui sous-tendent SHROOM3, le développement des reins, la fonction rénale et l’insuffisance rénale.
UNASSIGNED: SHROOM3 est une protéine unique puisqu’elle est la seule du groupe de protéines SHROOM à réguler la dynamique de l’actine par la constriction apicale et l’élongation des cellules apico-basales. SHROOM3 joue un rôle dichotomique dans le rein; de subtiles altérations de son expression et de sa fonction pouvant à la fois être pathologiques ou protectrices en contexte d’insuffisance rénale. Des études d’association pangénomiques ont permis d’identifier des variants génétiques associés à l’insuffisance rénale chronique près du site d’initiation de la transcription du gène SHROOM3. SHROOM3 semble également protéger la structure et la fonction des glomérules dans des contextes comme la glomérulosclérose segmentaire focale. On en sait toutefois peu sur les mécanismes précis qui entraînent cette protection; les partenaires de liaison de SHROOM3 demeurent par conséquent d’intéressantes avenues pour une étude plus approfondie.
UNASSIGNED: Notre recherche était limitée aux articles rédigés en anglais. Les études pertinentes n’ont pas fait l’objet d’une évaluation structurée de leur qualité. Un biais de sélection des articles inclus peut s’être produit. Bien que nous discutions des orientations et des possibilités futures, cette revue narrative reflète les points de vue académiques des auteurs.

Teucrium persicum Boiss. an Iranian endemic plant is used in Iranian traditional medicine. E-cadherin transmembrane protein participates in adherens junctions and is the main partner for β-catenin protein. The GC-MS analysis was used to detect the chemical constituents of the methanolic extract. Its effects on the transcription of the E-cadherin encoding gene, cellular levels, and localization of E-cadherin protein in PC-3 cells were investigated. About 70 chemical constituents were identified. Indirect immunofluorescence microscopy and western blotting results revealed the restoration of E-cadherin protein at cell adhesion contact sites in cells treated with T. persicum extract. Gene expression studies revealed that the extract increased the transcription of the E-cadherin encoding gene in PC-3 cells. These results suggest that T. persicum extract may contain potent compounds that provide further support for the anticancer properties of T. persicum. Surely, detailed molecular investigations are needed to find the mechanism(s) behind these effects.

The Drosophila eye develops from the larval eye disc, a flattened vesicle comprised of continuous retinal and peripodial epithelia (PE). The PE is an epithelium that plays a supporting role in retinal neurogenesis, but gives rise to cuticle in the adult. We report here that the PE is also necessary to preserve the morphology of the retinal epithelium. Depletion of the adherens junction (AJ) components β-Catenin (β-Cat), DE-Cadherin or α-Catenin from the PE leads to altered disc morphology, characterized by retinal displacement (RDis); so too does loss of the Ajuba protein Jub, an AJ-associated regulator of the transcriptional coactivator Yorkie (Yki). Restoring AJs or overexpressing Yki in β-Cat deficient PE results in suppression of RDis. Additional suppressors of AJ-dependent RDis include knockdown of Rho kinase (Rok) and Dystrophin (Dys). Furthermore, knockdown of βPS integrin (Mys) from the PE results in RDis, while overexpression of Mys can suppress RDis induced by the loss of β-Cat. We thus propose that AJ-Jub-Yki signaling in PE cells regulates PE cell contractile properties and/or attachment to the extracellular matrix to promote normal eye disc morphology.

The mechanical interactions of cells are mediated through adhesive interactions. In this study, we examined the growth, cellular behavior, and adhesion of MDCK epithelial cells on three different SiO2 substrates: amorphous glass coverslips and the silicon oxide layers that grow on ⟨111⟩ and ⟨100⟩ wafers. While compositionally all three substrates are almost similar, differences in surface energy result in dramatic differences in epithelial cell morphology, cell-cell adhesion, cell-substrate adhesion, actin organization, and extracellular matrix (ECM) protein expression. We also observe striking differences in ECM protein binding to the various substrates due to the hydrogen bond interactions. Our results demonstrate that MDCK cells have a robust response to differences in substrates that is not obviated by nanotopography or surface composition and that a cell\'s response may manifest through subtle differences in surface energies of the materials. This work strongly suggests that other properties of a material other than composition and topology should be considered when interpreting and controlling interactions of cells with a substrate, whether it is synthetic or natural.

Dietary salt intake in domestic fowl affects epithelial transport and morphology of the lower intestine (colon and coprodeum). This study investigated lower intestinal morphology and transport activity in two wild bird species with natural diets containing either low or high salt. Tissues from rock ptarmigan (Lagopus mutus) and common murres (Uria aalge) were sampled for histology and electrophysiological analyses. The ptarmigan exists on a low salt diet, while the murre lives on a high protein and high salt diet. The ptarmigan colon and coprodeum had villi/folds and crypts and the epithelium contained absorptive epithelial cells, mitochondria-rich cells and goblet cells. The colon had significant amiloride-inhibitable Isc, 5-15 μA/cm(2), with no glucose-stimulated Isc, and no significant phloridzin inhibition. The coprodeum also had high amiloride-inhibitable Isc. This transport pattern corresponded to that of chickens on low-salt diets. However, the ptarmigan colon also had a significant lysine/leucine-stimulated Isc of 3±1.0 μA/cm(2). The short U. aalge colon was similar to that of ptarmigans, but with no villi. It demonstrated a significant lysine/leucine-stimulated Isc (11±3.5 μA/cm(2)) with no amiloride-inhibitable Isc, similar to the high-salt chicken colon, but with no Na(+)-glucose cotransport. The murre coprodeum was inert to all substances and showed high resistance (1000 Ω·cm(2)), with a multilayered squamous epithelium. Despite some variations possibly associated with dietary protein intake, we conclude that natural high and low salt diets in different avian species are associated with different lower intestinal transport patterns, providing for post-renal adjustments in ion and water excretion.