Front Med (Lausanne)
November 2024
Peptide-based drugs are powerful inhibitors of therapeutically relevant protein-protein interactions. Their affinity and selectivity for target proteins are commonly assessed using fluorescence-based assays such as anisotropy/polarization or quantitative microarrays. This study reveals that labeling can perturb peptide/protein binding by more than 1 order of magnitude.
View Article and Find Full Text PDFThe vacuolar H-ATPase (V-ATPase) is a functionally conserved multimeric complex localized at the membranes of many organelles where its proton-pumping action is required for proper lumen acidification. The V-ATPase complex is composed of several subunits, some of which have been linked to human disease. We and others previously reported pathogenic dominantly acting variants in ATP6V1B2, the gene encoding the V1B2 subunit, as underlying a clinically variable phenotypic spectrum including dominant deafness-onychodystrophy (DDOD) syndrome, Zimmermann-Laband syndrome (ZLS), and deafness, onychodystrophy, osteodystrophy, intellectual disability, and seizures (DOORS) syndrome.
View Article and Find Full Text PDFThe identification of genes that confer either extension of life span or accelerate age-related decline was a step forward in understanding the mechanisms of aging and revealed that it is partially controlled by genetics and transcriptional programs. Here, we discovered that the human DNA sequence C16ORF70 encodes a protein, named MYTHO (macroautophagy and youth optimizer), which controls life span and health span. MYTHO protein is conserved from Caenorhabditis elegans to humans and its mRNA was upregulated in aged mice and elderly people.
View Article and Find Full Text PDFCasitas B-lineage lymphoma (CBL) encodes an adaptor protein with E3-ligase activity negatively controlling intracellular signaling downstream of receptor tyrosine kinases. Somatic CBL mutations play a driver role in a variety of cancers, particularly myeloid malignancies, whereas germline defects in the same gene underlie a RASopathy having clinical overlap with Noonan syndrome (NS) and predisposing to juvenile myelomonocytic leukemia and vasculitis. Other features of the disorder include cardiac defects, postnatal growth delay, cryptorchidism, facial dysmorphisms, and predisposition to develop autoimmune disorders.
View Article and Find Full Text PDFThe state of Rio Grande do Norte, located in the Northeast region of Brazil, has areas of granites and pegmatites with minerals that have varying concentrations of uranium. Consequently, high concentrations of radon gas, a carcinogenic substance for humans, can occur. The present study aimed to assess the occurrence of cancer and its association with exposure to sources of natural radioactivity using geological and geophysical information in the aforementioned state.
View Article and Find Full Text PDFmutations underlie a spectrum of early-onset neurodevelopmental phenotypes having developmental delay/intellectual disability (ID), epilepsy, and movement disorders (MD) as major clinical features. encodes the widely expressed heavy polypeptide of clathrin, a major component of the coated vesicles mediating endocytosis, intracellular trafficking, and synaptic vesicle recycling. The underlying pathogenic mechanism is largely unknown.
View Article and Find Full Text PDFParkinsonism Relat Disord
June 2023
Aim: To evaluate clinical phenotype and molecular findings of 157 cases with GNAO1 pathogenic or likely pathogenic variants delineating the clinical spectrum, course, and response to treatments.
Method: Clinical phenotype, genetic data, and pharmacological and surgical treatment history of 11 novel cases and 146 previously published patients were analyzed.
Results: Complex hyperkinetic movement disorder (MD) characterizes 88% of GNAO1 patients.
Over the last years, a constantly increasing number of genetic diseases associated with epilepsy and movement disorders have been recognized. An emerging group of conditions in this field is represented by genetic disorders affecting G-protein-coupled receptors (GPCRs)-cAMP signaling. This group of postsynaptic disorders includes genes encoding for proteins highly expressed in the central nervous system and involved in GPCR signal transduction and cAMP production (e.
View Article and Find Full Text PDFKrabbe disease (KD) is a rare lysosomal storage disorder caused by biallelic pathogenic variants in GALC. Most patients manifest the severe classic early-infantile form, while a small percentage of cases have later-onset types. We present two siblings with atypical clinical and neuroimaging phenotypes, compared to the classification of KD, who were found to carry biallelic loss-of-function GALC variants, including a recurrent 30 kb deletion and a previously unreported deep intronic variant that was identified by mRNA sequencing.
View Article and Find Full Text PDFPrompt diagnosis of complex phenotypes is a challenging task in clinical genetics. Whole exome sequencing has proved to be effective in solving such conditions. Here, we report on an unpredictable presentation of Werner Syndrome (WRNS) in a 12-year-old girl carrying a homozygous truncating variant in RECQL2, the gene mutated in WRNS, and a de novo activating missense change in PTPN11, the major Noonan syndrome gene, encoding SHP2, a protein tyrosine phosphatase positively controlling RAS function and MAPK signaling, which have tightly been associated with senescence in primary cells.
View Article and Find Full Text PDFJ Allergy Clin Immunol
July 2022
Background: Pathogenic missense variants in cell division control protein 42 (CDC42) differentially affect protein function, causing a clinically wide phenotypic spectrum variably affecting neurodevelopment, hematopoiesis, and immune response. More recently, 3 variants at the C-terminus of CDC42 were proposed to similarly impact protein function and cause a novel autoinflammatory disorder.
Objectives: We sought to clinically and functionally classify these variants to improve patient management.
J Clin Endocrinol Metab
February 2022
Context: Genes causing familial forms of diabetes mellitus are only partially known.
Objective: We set out to identify the genetic cause of hyperglycemia in multigenerational families with an apparent autosomal dominant form of adult-onset diabetes not due to mutations in known monogenic diabetes genes.
Methods: Existing whole-exome sequencing (WES) data were used to identify exonic variants segregating with diabetes in 60 families from the United States and Italy.
We developed a new class of inhibitors of protein-protein interactions of the SHP2 phosphatase, which is pivotal in cell signaling and represents a central target in the therapy of cancer and rare diseases. Currently available SHP2 inhibitors target the catalytic site or an allosteric pocket but lack specificity or are ineffective for disease-associated SHP2 mutants. Considering that pathogenic lesions cause signaling hyperactivation due to increased levels of SHP2 association with cognate proteins, we developed peptide-based molecules with nanomolar affinity for the N-terminal Src homology domain of SHP2, good selectivity, stability to degradation, and an affinity for pathogenic variants of SHP2 that is 2-20 times higher than for the wild-type protein.
View Article and Find Full Text PDFChemosensory receptors play a crucial role in distinguishing the wide range of volatile/soluble molecules by binding them with high accuracy. Chemosensation is the main sensory modality in organisms lacking long-range sensory mechanisms like vision/hearing. Despite its low number of sensory neurons, the nematode Caenorhabditis elegans possesses several chemosensory receptors, allowing it to detect about as many odorants as mammals.
View Article and Find Full Text PDFNeurofibromatosis 1 (NF1) is a disorder characterized by variable expressivity caused by loss-of-function variants in NF1, encoding neurofibromin, a protein negatively controlling RAS signaling. We evaluated whether concurrent variation in proteins functionally linked to neurofibromin contribute to the variable expressivity of NF1. Parallel sequencing of a RASopathy gene panel in 138 individuals with molecularly confirmed clinical diagnosis of NF1 identified missense variants in PTPN11, encoding SHP2, a positive regulator of RAS signaling, in four subjects from three unrelated families.
View Article and Find Full Text PDFThe RASopathies are a family of clinically related disorders caused by mutations affecting genes participating in the RAS-MAPK signaling cascade. Among them, Noonan syndrome (NS) and Noonan syndrome with multiple lentigines (NSML) are allelic conditions principally associated with dominant mutations in PTPN11, which encodes the nonreceptor SH2 domain-containing protein tyrosine phosphatase SHP2. Individual PTPN11 mutations are specific to each syndrome and have opposite consequences on catalysis, but all favor SHP2's interaction with signaling partners.
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