The extracellular and intracellular regions of Crb2a play distinct roles in guiding the formation of the apical zonula adherens

Diverse functions and pathogenetic role of Crumbs in retinopathy

The Crumbs protein (CRB) family plays a crucial role in maintaining the apical-basal polarity and integrity of embryonic epithelia. The family comprises different isoforms in different animals and possesses diverse structural, localization, and functional characteristics. Mutations in the human CRB1 or CRB2 gene may lead to a broad spectrum of retinal dystrophies. Various CRB-associated experimental models have recently provided mechanistic insights into human CRB-associated retinopathies. The knowledge obtained from these models corroborates the importance of CRB in retinal development and maintenance. Therefore, complete elucidation of these models can provide excellent therapeutic prospects for human CRB-associated retinopathies. In this review, we summarize the current animal models and human-derived models of different CRB family members and describe the main characteristics of their retinal phenotypes.

Polystyrene nanoplastics affected the nutritional quality of Chlamys farreri through disturbing the function of gills and physiological metabolism: Comparison with microplastics

Although microplastics (MPs) and nanoplastics (NPs) have become a global concern because of their possible hazards to marine organisms, few studies have investigated the effects of MPs/NPs on the nutritional quality of marine economic species, and the toxicity mechanisms remain unclear. We therefore investigated the effects of polystyrene MPs (PS-MPs, 5 μm) and NPs (PS-NPs, 100 nm) at an environmentally relevant concentration on adult scallops Chlamys farreri through the determination of nutritional composition, physiological metabolism, enzymatic response, and histopathology. Results showed that plastic particles significantly decreased the plumpness (by 33.32 % for PS-MPs and 36.69 % for PS-NPs) and protein content of the adductor muscle (by 4.88 % for PS-MPs and 8.77 % for PS-NPs) in scallops, with PS-NPs causing more notable impacts than PS-MPs. Based on the integrated biomarker response analysis, PS-NPs exhibited greater toxicity than PS-MPs, suggesting a size-dependent effect for plastic particle. Furthermore, PS-NPs significantly affected the physiological metabolism (e.g., filtration and ammonia excretion) than PS-MPs. Using gill transcriptomics analysis, the key toxicological mechanisms caused by NPs exposure included enrichment of the mitophagy pathway, responses to oxidative stress, and changes related to genes associated with nerves. This study provides new insights into the potential negative effects of MPs/NPs on the mariculture industry.

Inducible Pluripotent Stem Cells to Model and Treat Inherited Degenerative Diseases of the Outer Retina: 3D-Organoids Limitations and Bioengineering Solutions

Inherited retinal degenerations (IRD) affecting either photoreceptors or pigment epithelial cells cause progressive visual loss and severe disability, up to complete blindness. Retinal organoids (ROs) technologies opened up the development of human inducible pluripotent stem cells (hiPSC) for disease modeling and replacement therapies. However, hiPSC-derived ROs applications to IRD presently display limited maturation and functionality, with most photoreceptors lacking well-developed outer segments (OS) and light responsiveness comparable to their adult retinal counterparts. In this review, we address for the first time the microenvironment where OS mature, i.e., the subretinal space (SRS), and discuss SRS role in photoreceptors metabolic reprogramming required for OS generation. We also address bioengineering issues to improve culture systems proficiency to promote OS maturation in hiPSC-derived ROs. This issue is crucial, as satisfying the demanding metabolic needs of photoreceptors may unleash hiPSC-derived ROs full potential for disease modeling, drug development, and replacement therapies.