RESUMO
Diamond-Blackfan anemia (DBA) is predominantly underlined by mutations in genes encoding ribosomal proteins (RP); however, its etiology remains unexplained in approximately 25 % of patients. We previously reported a novel heterozygous RPS7 mutation hg38 chr2:g.3,580,153G > T p.V134F in one female patient and two asymptomatic family members, in whom mild anemia and increased erythrocyte adenosine deaminase (eADA) activity were detected. We observed that altered erythrocyte metabolism and oxidative stress which may negatively affect the lifespan of erythrocytes distinguishes the patient from her asymptomatic family members. Pathogenicity of the RPS7 p.V134F mutation was extensively validated including molecular defects in protein translational activity and ribosomal stress activation in the cellular model of this variant.
Assuntos
Anemia de Diamond-Blackfan , Proteínas Ribossômicas , Anemia de Diamond-Blackfan/genética , Eritrócitos/metabolismo , Feminino , Humanos , Mutação de Sentido Incorreto , Biossíntese de Proteínas , Proteínas Ribossômicas/genéticaRESUMO
CFTR is a membrane protein that functions as an ion channel. Mutations that disrupt its biosynthesis, trafficking or function cause cystic fibrosis (CF). Here, we present a novel in vitro model system prepared using CRISPR/Cas9 genome editing with endogenously expressed WT-CFTR tagged with a HiBiT peptide. To enable the detection of CFTR in the plasma membrane of live cells, we inserted the HiBiT tag in the fourth extracellular loop of WT-CFTR. The 11-amino acid HiBiT tag binds with high affinity to a large inactive subunit (LgBiT), generating a reporter luciferase with bright luminescence. Nine homozygous clones with the HiBiT knock-in were identified from the 182 screened clones; two were genetically and functionally validated. In summary, this work describes the preparation and validation of a novel reporter cell line with the potential to be used as an ultimate building block for developing unique cellular CF models by CRISPR-mediated insertion of CF-causing mutations.
Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística , Fibrose Cística , Humanos , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Sistemas CRISPR-Cas/genética , Fibrose Cística/genética , Fibrose Cística/metabolismo , Membrana Celular/metabolismo , Linhagem CelularRESUMO
The global shortage of corneal endothelial graft tissue necessitates the exploration of alternative therapeutic strategies. Rho-associated protein kinase inhibitors (ROCKi), recognized for their regenerative potential in cardiology, oncology, and neurology, have shown promise in corneal endothelial regeneration. This study investigates the repurposing potential of additional ROCKi compounds. Through screening a self-assembled library of ROCKi on B4G12 corneal endothelial cells, we evaluated their dose-dependent effects on proliferation, migration, and toxicity using live-cell imaging. Nine ROCKi candidates significantly enhanced B4G12 proliferation compared to the basal growth rate. These candidates were further assessed for their potential to accelerate wound closure as another indicator for tissue regeneration capacity, with most demonstrating notable efficacy. To assess the potential impact of candidate ROCKi on key corneal endothelial cell markers related to cell proliferation, leaky tight junctions and ion efflux capacity, we analyzed the protein expression of cyclin E1, CDK2, p16, ZO-1 and Na+/K+-ATPase, respectively. Immunocytochemistry and western blot analysis confirmed the preservation of corneal endothelial markers post-treatment with ROCKi hits. However, notable cytoplasm enlargement and nuclear fragmentation were detected after the treatment with SR-3677 and Thiazovivin, indicating possible cellular stress. In compared parameters, Chroman-1 at a concentration of 10â¯nM outperformed other ROCKi, requiring significantly 1000-fold lower effective concentration than established ROCKi Y-27632 and Fasudil. Altogether, this study underscores the potential of repurposing ROCKi for treating corneal endothelial dysfunctions, offering a viable alternative to conventional grafting methods, and highlights Chroman-1 as a promising candidate structure for hit-to-lead development.
Assuntos
Proliferação de Células , Endotélio Corneano , Inibidores de Proteínas Quinases , Regeneração , Quinases Associadas a rho , Quinases Associadas a rho/antagonistas & inibidores , Quinases Associadas a rho/metabolismo , Proliferação de Células/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Endotélio Corneano/efeitos dos fármacos , Regeneração/efeitos dos fármacos , Animais , Reposicionamento de Medicamentos , Movimento Celular/efeitos dos fármacos , Linhagem Celular , Humanos , Células Endoteliais/efeitos dos fármacosRESUMO
Cystic fibrosis (CF) is the most common autosomal recessive genetic disease in Caucasians, affecting more than 100,000 individuals worldwide. It is caused by pathogenic variants in the gene encoding CFTR, an anion channel at the plasma membrane of epithelial and other cells. Many CF pathogenic variants disrupt the biosynthesis and trafficking of CFTR or reduce its ion channel function. The most frequent mutation, loss of a phenylalanine at position 508 (F508del), leads to misfolding, retention in the endoplasmic reticulum, and premature degradation of the protein. The therapeutics available for treating CF lung disease include antibiotics, mucolytics, bronchodilators, physiotherapy, and most recently CFTR modulators. To date, no cure for this life shortening disease has been found. Treatment with the Triple combination drug therapy, TRIKAFTA®, is composed of three drugs: Elexacaftor (VX-445), Tezacaftor (VX-661) and Ivacaftor (VX-770). This therapy, benefits persons with CF, improving their weight, lung function, energy levels (as defined by reduced fatigue), and overall quality of life. We examined the effect of combining LAU-7b oral treatment and Triple therapy combination on lung function in a F508deltm1EUR mouse model that displays lung abnormalities relevant to human CF. We assessed lung function, lung histopathology, protein oxidation, lipid oxidation, and fatty acid and lipid profiles in F508deltm1EUR mice.