RESUMO
The design of proteins that can bind any RNA sequence of interest has many potential biological and medical applications. Here we have expanded the recognition of Pumilio and FBF homology protein (PUF) repeats beyond adenine, guanine and uracil and evolved them to specifically bind cytosine. These repeat sequences can be used to create PUF domains capable of selectively binding RNA targets of diverse sequence and structure.
Assuntos
Citosina/metabolismo , Engenharia de Proteínas , Proteínas de Ligação a RNA/metabolismo , RNA/metabolismo , Ensaio de Desvio de Mobilidade Eletroforética , Humanos , Mutação , RNA/química , RNA/genética , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/genética , Sequências Repetitivas de Aminoácidos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Técnicas do Sistema de Duplo-HíbridoRESUMO
Our previous neurocognitive studies of schizophrenia outlined two clusters of affected subjects--cognitively spared (CS) and cognitive deficit (CD), the latter's characteristics pointing to developmental origins and impaired synaptic plasticity. Here we investigate the contribution of polymorphisms in major regulators of these processes to susceptibility to schizophrenia and to CD in patients. We examine variation in genes encoding proteins at the gateway of Reelin signaling: ligands RELN and APOE, their common receptors APOER2 and VLDLR, and adaptor DAB1. Association analysis with disease outcome and cognitive performance in the Western Australian Family Study of Schizophrenia (WAFSS) was followed by replication analysis in the Australian Schizophrenia Research Bank (ASRB) and in the Health in Men Study (HIMS) of normal aging males. In the WAFSS sample, we observed significant association of APOE, APOER2, VLDLR, and DAB1 SNPs with disease outcome in the case-control and CD-control datasets, and with pre-morbid intelligence and verbal memory in cases. HIMS replication analysis supported rs439401 (APOE regulatory region), and rs2297660 and rs3737983 (APOER2), with an effect on memory performance in normal aging subjects consistent with the findings in schizophrenia cases. APOER2 gene expression analysis revealed lower transcript levels in lymphoblastoid cells from cognitively impaired schizophrenia patients of the alternatively spliced exon 19, mediating Reelin signaling and synaptic plasticity in the adult brain. ASRB replication analysis produced marginally significant results, possibly reflecting a recruitment strategy biased toward CS patients. The data suggest a contribution of neurodevelopmental/synaptic plasticity genes to cognitive impairment in schizophrenia.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Apolipoproteínas E/genética , Moléculas de Adesão Celular Neuronais/genética , Cognição/fisiologia , Proteínas da Matriz Extracelular/genética , Proteínas do Tecido Nervoso/genética , Receptores de LDL/genética , Esquizofrenia/fisiopatologia , Serina Endopeptidases/genética , Transdução de Sinais/genética , Adulto , Cromossomos Humanos Par 19/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Proteínas Relacionadas a Receptor de LDL/genética , Ligantes , Masculino , Característica Quantitativa Herdável , Proteína Reelina , Reprodutibilidade dos Testes , Fatores de Risco , Esquizofrenia/genética , Austrália OcidentalRESUMO
BACKGROUND: Skin is the largest and most visible organ of the body. Many of its functions include temperature regulation, immunity from microorganisms, maintaining electrolyte balance, and protection from physical injuries, chemical agents and ultraviolet (UV) radiation. Aging occurs in every layer of the skin, primarily due to the degradation of its components. Induction of degradative enzymes and the abundant production of reactive oxygen species lead to skin aging. Understanding the complexity of skin structure and factors contributing to the skin aging will help us impede the aging process. Applications of anti-aging products are a common method to prevent or repair damages that lead to aging. CONCLUSION: This review will provide information on the causes and indicators of skin aging as well as examine studies that have used plants to produce anti-aging products.
Assuntos
Extratos Vegetais/uso terapêutico , Envelhecimento da Pele/efeitos dos fármacos , Animais , Humanos , Fenômenos Fisiológicos da Pele/efeitos dos fármacosRESUMO
BACKGROUND: Genome-wide and candidate gene association studies have previously revealed links between a predisposition to acute lymphoblastic leukemia (ALL) and genetic polymorphisms in the following genes: IKZF1 (7p12.2; ID: 10320), DDC (7p12.2; ID: 1644), CDKN2A (9p21.3; ID: 1029), CEBPE (14q11.2; ID: 1053), and LMO1 (11p15; ID: 4004). In this study, we aimed to conduct an investigation into the possible association between polymorphisms in these genes and ALL within a sample of Yemeni children of Arab-Asian descent. METHODS: Seven single-nucleotide polymorphisms (SNPs) in IKZF1, three SNPs in DDC, two SNPs in CDKN2A, two SNPs in CEBPE, and three SNPs in LMO1 were genotyped in 289 Yemeni children (136 cases and 153 controls), using the nanofluidic Dynamic Array (Fluidigm 192.24 Dynamic Array). Logistic regression analyses were used to estimate ALL risk, and the strength of association was expressed as odds ratios with 95% confidence intervals. RESULTS: We found that the IKZF1 SNP rs10235796 C allele (p = 0.002), the IKZF1 rs6964969 A>G polymorphism (p = 0.048, GG vs. AA), the CDKN2A rs3731246 G>C polymorphism (p = 0.047, GC+CC vs. GG), and the CDKN2A SNP rs3731246 C allele (p = 0.007) were significantly associated with ALL in Yemenis of Arab-Asian descent. In addition, a borderline association was found between IKZF1 rs4132601 T>G variant and ALL risk. No associations were found between the IKZF1 SNPs (rs11978267; rs7789635), DDC SNPs (rs3779084; rs880028; rs7809758), CDKN2A SNP (rs3731217), the CEBPE SNPs (rs2239633; rs12434881) and LMO1 SNPs (rs442264; rs3794012; rs4237770) with ALL in Yemeni children. CONCLUSION: The IKZF1 SNPs, rs10235796 and rs6964969, and the CDKN2A SNP rs3731246 (previously unreported) could serve as risk markers for ALL susceptibility in Yemeni children.
Assuntos
Inibidor de Quinase Dependente de Ciclina p18/genética , Fator de Transcrição Ikaros/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Adolescente , Alelos , Descarboxilases de Aminoácido-L-Aromático/genética , Povo Asiático/genética , Biomarcadores Tumorais/sangue , Proteínas Estimuladoras de Ligação a CCAAT/genética , Estudos de Casos e Controles , Criança , Pré-Escolar , Inibidor p16 de Quinase Dependente de Ciclina , Proteínas de Ligação a DNA/genética , Feminino , Frequência do Gene , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla/métodos , Humanos , Proteínas com Domínio LIM/genética , Masculino , Polimorfismo Genético/genética , Polimorfismo de Nucleotídeo Único , Fatores de Risco , Fatores de Transcrição/genética , IêmenRESUMO
Pentatricopeptide repeat (PPR) proteins control diverse aspects of RNA metabolism in eukaryotic cells. Although recent computational and structural studies have provided insights into RNA recognition by PPR proteins, their highly insoluble nature and inconsistencies between predicted and observed modes of RNA binding have restricted our understanding of their biological functions and their use as tools. Here we use a consensus design strategy to create artificial PPR domains that are structurally robust and can be programmed for sequence-specific RNA binding. The atomic structures of these artificial PPR domains elucidate the structural basis for their stability and modelling of RNA-protein interactions provides mechanistic insights into the importance of RNA-binding residues and suggests modes of PPR-RNA association. The modular mode of RNA binding by PPR proteins holds great promise for the engineering of new tools to target RNA and to understand the mechanisms of gene regulation by natural PPR proteins.
Assuntos
Proteínas Mitocondriais/química , Proteínas de Ligação a RNA/química , RNA/química , Motivos de Aminoácidos , Arabidopsis/genética , Arabidopsis/metabolismo , Sítios de Ligação , Regulação da Expressão Gênica , Humanos , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Ligação Proteica , Engenharia de Proteínas , Estabilidade Proteica , Estrutura Terciária de Proteína , RNA/genética , RNA/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismoRESUMO
Mammalian pentatricopeptide repeat domain (PPR) proteins are involved in regulation of mitochondrial RNA metabolism and translation and are required for mitochondrial function. We investigated an uncharacterised PPR protein, the supernumerary mitochondrial ribosomal protein of the small subunit 27 (MRPS27), and show that it associates with the 12S rRNA and tRNA(Glu), however it does not affect their abundance. We found that MRPS27 is not required for mitochondrial RNA processing or the stability of the small ribosomal subunit. However, MRPS27 is required for mitochondrial protein synthesis and its knockdown causes decreased abundance in respiratory complexes and cytochrome c oxidase activity.