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1.
Genome Res ; 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39271292

RESUMO

Maize phenotypes are plastic, determined by the complex interplay of genetics and environmental variables. Uncovering the genes responsible and understanding how their effects change across a large geographic region are challenging. In this study, we conducted systematic analysis to identify environmental indices that strongly influence 19 traits (including flowering time, plant architecture, and yield component traits) measured in the maize nested association mapping (NAM) population grown in 11 environments. Identified environmental indices based on day length, temperature, moisture, and combinations of these are biologically meaningful. Next, we leveraged a total of more than 20 million SNP and SV markers derived from recent de novo sequencing of the NAM founders for trait prediction and dissection. When combined with identified environmental indices, genomic prediction enables accurate performance predictions. Genome-wide association studies (GWASs) detected genetic loci associated with the plastic response to the identified environmental indices for all examined traits. By systematically uncovering the major environmental and genomic factors underlying phenotypic plasticity in a wide variety of traits and depositing our results as a track on the MaizeGDB genome browser, we provide a community resource as well as a comprehensive analytical framework to facilitate continuing complex trait dissection and prediction in maize and other crops. Our findings also provide a conceptual framework for the genetic architecture of phenotypic plasticity by accommodating two alternative models, regulatory gene model and allelic sensitivity model, as special cases of a continuum.

2.
Proc Natl Acad Sci U S A ; 121(34): e2408551121, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39145934

RESUMO

The first steps of vision take place in the ciliary outer segment compartment of photoreceptor cells. The protein composition of outer segments is uniquely suited to perform this function. The most abundant among these proteins is the visual pigment, rhodopsin, whose outer segment trafficking involves intraflagellar transport (IFT). Here, we report three major findings from the analysis of mice in which ciliary transport was acutely impaired by conditional knockouts of IFT-B subunits. First, we demonstrate the existence of a sorting mechanism whereby mislocalized rhodopsin is recruited to and concentrated in extracellular vesicles prior to their release, presumably to protect the cell from adverse effects of protein mislocalization. Second, reducing rhodopsin expression significantly delays photoreceptor degeneration caused by IFT disruption, suggesting that controlling rhodopsin levels may be an effective therapy for some cases of retinal degenerative disease. Last, the loss of IFT-B subunits does not recapitulate a phenotype observed in mutants of the BBSome (another ciliary transport protein complex relying on IFT) in which non-ciliary proteins accumulate in the outer segment. Whereas it is widely thought that the role of the BBSome is to primarily participate in ciliary transport, our data suggest that the BBSome has another major function independent of IFT and possibly related to maintaining the diffusion barrier of the ciliary transition zone.


Assuntos
Camundongos Knockout , Rodopsina , Animais , Camundongos , Rodopsina/metabolismo , Cílios/metabolismo , Transporte Proteico , Transporte Biológico , Flagelos/metabolismo , Compartimento Celular , Vesículas Extracelulares/metabolismo
3.
Genes Dev ; 33(1-2): 61-74, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30573454

RESUMO

Chromosomal translocations of the Mixed-lineage leukemia 1 (MLL1) gene generate MLL chimeras that drive the pathogenesis of acute myeloid and lymphoid leukemia. The untranslocated MLL1 is a substrate for proteolytic cleavage by the endopeptidase threonine aspartase 1 (taspase1); however, the biological significance of MLL1 cleavage by this endopeptidase remains unclear. Here, we demonstrate that taspase1-dependent cleavage of MLL1 results in the destabilization of MLL. Upon loss of taspase1, MLL1 association with chromatin is markedly increased due to the stabilization of its unprocessed version, and this stabilization of the uncleaved MLL1 can result in the displacement of MLL chimeras from chromatin in leukemic cells. Casein kinase II (CKII) phosphorylates MLL1 proximal to the taspase1 cleavage site, facilitating its cleavage, and pharmacological inhibition of CKII blocks taspase1-dependent MLL1 processing, increases MLL1 stability, and results in the displacement of the MLL chimeras from chromatin. Accordingly, inhibition of CKII in a MLL-AF9 mouse model of leukemia delayed leukemic progression in vivo. This study provides insights into the direct regulation of the stability of MLL1 through its cleavage by taspase1, which can be harnessed for targeted therapeutic approaches for the treatment of aggressive leukemia as the result of MLL translocations.


Assuntos
Endopeptidases/metabolismo , Leucemia/terapia , Proteína de Leucina Linfoide-Mieloide/genética , Animais , Cromatina/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Endopeptidases/genética , Inibidores Enzimáticos/farmacologia , Técnicas de Inativação de Genes , Células HCT116 , Células HEK293 , Humanos , Leucemia/enzimologia , Leucemia/genética , Células MCF-7 , Camundongos , Proteína de Leucina Linfoide-Mieloide/metabolismo , Estabilidade Proteica , Análise de Sobrevida
4.
Proc Natl Acad Sci U S A ; 120(12): e2215011120, 2023 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-36917665

RESUMO

The photoreceptor outer segment is a modified cilium filled with hundreds of flattened "disc" membranes responsible for efficient light capture. To maintain photoreceptor health and functionality, outer segments are continuously renewed through the addition of new discs at their base. This process is driven by branched actin polymerization nucleated by the Arp2/3 complex. To induce actin polymerization, Arp2/3 requires a nucleation promoting factor. Here, we show that the nucleation promoting factor driving disc morphogenesis is the pentameric WAVE complex and identify all protein subunits of this complex. We further demonstrate that the knockout of one of them, WASF3, abolishes actin polymerization at the site of disc morphogenesis leading to formation of disorganized membrane lamellae emanating from the photoreceptor cilium instead of an outer segment. These data establish that, despite the intrinsic ability of photoreceptor ciliary membranes to form lamellar structures, WAVE-dependent actin polymerization is essential for organizing these membranes into a proper outer segment.


Assuntos
Actinas , Cílios , Actinas/metabolismo , Cílios/química , Células Fotorreceptoras/metabolismo , Citoplasma , Morfogênese
5.
Bioinformatics ; 40(2)2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38337024

RESUMO

SUMMARY: Understanding the effects of genetic variants is crucial for accurately predicting traits and functional outcomes. Recent approaches have utilized artificial intelligence and protein language models to score all possible missense variant effects at the proteome level for a single genome, but a reliable tool is needed to explore these effects at the pan-genome level. To address this gap, we introduce a new tool called PanEffect. We implemented PanEffect at MaizeGDB to enable a comprehensive examination of the potential effects of coding variants across 50 maize genomes. The tool allows users to visualize over 550 million possible amino acid substitutions in the B73 maize reference genome and to observe the effects of the 2.3 million natural variations in the maize pan-genome. Each variant effect score, calculated from the Evolutionary Scale Modeling (ESM) protein language model, shows the log-likelihood ratio difference between B73 and all variants in the pan-genome. These scores are shown using heatmaps spanning benign outcomes to potential functional consequences. In addition, PanEffect displays secondary structures and functional domains along with the variant effects, offering additional functional and structural context. Using PanEffect, researchers now have a platform to explore protein variants and identify genetic targets for crop enhancement. AVAILABILITY AND IMPLEMENTATION: The PanEffect code is freely available on GitHub (https://github.com/Maize-Genetics-and-Genomics-Database/PanEffect). A maize implementation of PanEffect and underlying datasets are available at MaizeGDB (https://www.maizegdb.org/effect/maize/).


Assuntos
Bases de Dados Genéticas , Zea mays , Zea mays/genética , Inteligência Artificial , Genoma de Planta , Fenótipo , Software
6.
BMC Genomics ; 25(1): 533, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38816789

RESUMO

BACKGROUND: Environmental stress factors, such as biotic and abiotic stress, are becoming more common due to climate variability, significantly affecting global maize yield. Transcriptome profiling studies provide insights into the molecular mechanisms underlying stress response in maize, though the functions of many genes are still unknown. To enhance the functional annotation of maize-specific genes, MaizeGDB has outlined a data-driven approach with an emphasis on identifying genes and traits related to biotic and abiotic stress. RESULTS: We mapped high-quality RNA-Seq expression reads from 24 different publicly available datasets (17 abiotic and seven biotic studies) generated from the B73 cultivar to the recent version of the reference genome B73 (B73v5) and deduced stress-related functional annotation of maize gene models. We conducted a robust meta-analysis of the transcriptome profiles from the datasets to identify maize loci responsive to stress, identifying 3,230 differentially expressed genes (DEGs): 2,555 DEGs regulated in response to abiotic stress, 408 DEGs regulated during biotic stress, and 267 common DEGs (co-DEGs) that overlap between abiotic and biotic stress. We discovered hub genes from network analyses, and among the hub genes of the co-DEGs we identified a putative NAC domain transcription factor superfamily protein (Zm00001eb369060) IDP275, which previously responded to herbivory and drought stress. IDP275 was up-regulated in our analysis in response to eight different abiotic and four different biotic stresses. A gene set enrichment and pathway analysis of hub genes of the co-DEGs revealed hormone-mediated signaling processes and phenylpropanoid biosynthesis pathways, respectively. Using phylostratigraphic analysis, we also demonstrated how abiotic and biotic stress genes differentially evolve to adapt to changing environments. CONCLUSIONS: These results will help facilitate the functional annotation of multiple stress response gene models and annotation in maize. Data can be accessed and downloaded at the Maize Genetics and Genomics Database (MaizeGDB).


Assuntos
Anotação de Sequência Molecular , Estresse Fisiológico , Transcriptoma , Zea mays , Zea mays/genética , Estresse Fisiológico/genética , Regulação da Expressão Gênica de Plantas , Perfilação da Expressão Gênica , Genes de Plantas
7.
BMC Microbiol ; 24(1): 326, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39243017

RESUMO

BACKGROUND: ​​The genus Fusarium poses significant threats to food security and safety worldwide because numerous species of the fungus cause destructive diseases and/or mycotoxin contamination in crops. The adverse effects of climate change are exacerbating some existing threats and causing new problems. These challenges highlight the need for innovative solutions, including the development of advanced tools to identify targets for control strategies. DESCRIPTION: In response to these challenges, we developed the Fusarium Protein Toolkit (FPT), a web-based tool that allows users to interrogate the structural and variant landscape within the Fusarium pan-genome. The tool displays both AlphaFold and ESMFold-generated protein structure models from six Fusarium species. The structures are accessible through a user-friendly web portal and facilitate comparative analysis, functional annotation inference, and identification of related protein structures. Using a protein language model, FPT predicts the impact of over 270 million coding variants in two of the most agriculturally important species, Fusarium graminearum and F. verticillioides. To facilitate the assessment of naturally occurring genetic variation, FPT provides variant effect scores for proteins in a Fusarium pan-genome based on 22 diverse species. The scores indicate potential functional consequences of amino acid substitutions and are displayed as intuitive heatmaps using the PanEffect framework. CONCLUSION: FPT fills a knowledge gap by providing previously unavailable tools to assess structural and missense variation in proteins produced by Fusarium. FPT has the potential to deepen our understanding of pathogenic mechanisms in Fusarium, and aid the identification of genetic targets for control strategies that reduce crop diseases and mycotoxin contamination. Such targets are vital to solving the agricultural problems incited by Fusarium, particularly evolving threats resulting from climate change. Thus, FPT has the potential to contribute to improving food security and safety worldwide.


Assuntos
Proteínas Fúngicas , Fusarium , Internet , Fusarium/genética , Fusarium/metabolismo , Fusarium/classificação , Proteínas Fúngicas/genética , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Genoma Fúngico/genética , Variação Genética , Modelos Moleculares , Software , Conformação Proteica
8.
Surg Endosc ; 38(10): 5778-5784, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39143330

RESUMO

BACKGROUND: Combat casualties are frequently injured in austere settings where modern imaging modalities are unavailable. Exploratory laparotomies are often performed in these settings when there is suspicion for intra-abdominal injury. Prior studies of combat casualties reported non-therapeutic laparotomy (NTL) rates as high as 32%. Given improvements in combat casualty care over time, we evaluated NTLs performed during later years of the wars in Iraq and Afghanistan. METHODS: Military personnel with combat-related injuries (6/1/2009-12/31/2014) who underwent exploratory laparotomy based on concern for abdominal injury (i.e. not performed for proximal vascular control or fecal diversion) and were evacuated to Landstuhl Regional Medical Center (Germany) before being transferred to participating U.S. military hospitals were assessed. An NTL was defined as a negative laparotomy without substantial intra-abdominal injuries requiring repair. Characteristics, indications for laparotomy, operative findings, and outcomes were examined. RESULTS: Among 244 patients who underwent laparotomies, 41 (16.8%) had NTLs and 203 (83.2%) had therapeutic laparotomies (i.e. positive findings). Patients with NTLs had more computed tomography scans concerning for injury (48.8% vs 27.1%; p = 0.006), less penetrating injury mechanisms (43.9% vs 71.9%; p < 0.001), and lower Injury Severity Scores (26 vs 33; p = 0.003) compared to patients with therapeutic laparotomies. Patients with NTLs were also less likely to be admitted to the intensive care unit (70.7 vs 89.2% for patients with therapeutic laparotomies; p = 0.007). No patients with NTLs developed abdominal surgical site infections (SSI) compared to 16.7% of patients with therapeutic laparotomies (p = 0.002). There was no significant difference in mortality between the groups (p = 0.198). CONCLUSIONS: Our proportion of NTLs was lower than reported from earlier years during the wars in Iraq and Afghanistan. No infectious complications from NTLs (i.e. abdominal SSIs) were identified. Nevertheless, surgeons should continue to have a low threshold for exploratory laparotomy in military patients in austere settings with concern for intra-abdominal injury.


Assuntos
Traumatismos Abdominais , Campanha Afegã de 2001- , Guerra do Iraque 2003-2011 , Laparotomia , Militares , Humanos , Laparotomia/métodos , Masculino , Traumatismos Abdominais/cirurgia , Adulto , Feminino , Adulto Jovem , Estudos Retrospectivos , Estados Unidos , Lesões Relacionadas à Guerra/cirurgia
9.
J Proteome Res ; 22(8): 2703-2713, 2023 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-37493966

RESUMO

Photoreceptor cells generate neuronal signals in response to capturing light. This process, called phototransduction, takes place in a highly specialized outer segment organelle. There are significant discrepancies in the reported amounts of many proteins supporting this process, particularly those of low abundance, which limits our understanding of their molecular organization and function. In this study, we used quantitative mass spectrometry to simultaneously determine the abundances of 20 key structural and functional proteins residing in mouse rod outer segments. We computed the absolute number of molecules of each protein residing within an individual outer segment and the molar ratio among all 20 proteins. The molar ratios of proteins comprising three well-characterized constitutive complexes in outer segments differed from the established subunit stoichiometries of these complexes by less than 7%, highlighting the exceptional precision of our quantification. Overall, this study resolves multiple existing discrepancies regarding the outer segment abundances of these proteins, thereby advancing our understanding of how the phototransduction pathway functions as a single, well-coordinated molecular ensemble.


Assuntos
Proteínas , Segmento Externo da Célula Bastonete , Animais , Camundongos , Proteínas/metabolismo , Segmento Externo da Célula Bastonete/metabolismo , Transdução de Sinal Luminoso , Retina/metabolismo
10.
Clin Infect Dis ; 76(6): 1080-1087, 2023 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-36303432

RESUMO

BACKGROUND: Cryptococcal meningitis is a common cause of AIDS-related mortality. Although symptom recurrence after initial treatment is common, the etiology is often difficult to decipher. We sought to summarize characteristics, etiologies, and outcomes among persons with second-episode symptomatic recurrence. METHODS: We prospectively enrolled Ugandans with cryptococcal meningitis and obtained patient characteristics, antiretroviral therapy (ART) and cryptococcosis histories, clinical outcomes, and cerebrospinal fluid (CSF) analysis results. We independently adjudicated cases of second-episode meningitis to categorize patients as (1) microbiological relapse, (2) paradoxical immune reconstitution inflammatory syndrome (IRIS), (3) persistent elevated intracranial pressure (ICP) only, or (4) persistent symptoms only, along with controls of primary cryptococcal meningitis. We compared groups with chi-square or Kruskal-Wallis tests as appropriate. RESULTS: 724 participants were included (n = 607 primary episode, 81 relapse, 28 paradoxical IRIS, 2 persistently elevated ICP, 6 persistent symptoms). Participants with culture-positive relapse had lower CD4 (25 cells/µL; IQR: 9-76) and lower CSF white blood cell (WBC; 4 cells/µL; IQR: 4-85) counts than paradoxical IRIS (CD4: 78 cells/µL; IQR: 47-142; WBC: 45 cells/µL; IQR: 8-128). Among those with CSF WBC <5 cells/µL, 86% (43/50) had relapse. Among those with CD4 counts <50 cells/µL, 91% (39/43) had relapse. Eighteen-week mortality (from current symptom onset) was 47% among first episodes of cryptococcal meningitis, 31% in culture-positive relapses, and 14% in paradoxical IRIS. CONCLUSIONS: Poor immune reconstitution was noted more often in relapse than IRIS as evidenced by lower CSF WBC and blood CD4 counts. These easily obtained laboratory values should prompt initiation of antifungal treatment while awaiting culture results. CLINICAL TRIALS REGISTRATION: NCT01802385.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS , Infecções por HIV , Meningite Criptocócica , Humanos , Meningite Criptocócica/diagnóstico , Meningite Criptocócica/tratamento farmacológico , Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Antifúngicos/uso terapêutico , Recidiva
11.
Chem Rev ; 121(22): 13797-13868, 2021 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-34157230

RESUMO

Researchers have worked for many decades to master the rules of biomolecular design that would allow artificial biopolymer complexes to self-assemble and function similarly to the diverse biochemical constructs displayed in natural biological systems. The rules of nucleic acid assembly (dominated by Watson-Crick base-pairing) have been less difficult to understand and manipulate than the more complicated rules of protein folding. Therefore, nucleic acid nanotechnology has advanced more quickly than de novo protein design, and recent years have seen amazing progress in DNA and RNA design. By combining structural motifs with aptamers that act as affinity handles and add powerful molecular recognition capabilities, nucleic acid-based self-assemblies represent a diverse toolbox for use by bioengineers to create molecules with potentially revolutionary biological activities. In this review, we focus on the development of self-assembling nucleic acid nanostructures that are functionalized with nucleic acid aptamers and their great potential in wide ranging application areas.


Assuntos
Nanoestruturas , Ácidos Nucleicos , Nanoestruturas/química , Nanotecnologia , Conformação de Ácido Nucleico , Ácidos Nucleicos/química , Oligonucleotídeos
12.
Aging Ment Health ; 27(2): 350-356, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35583075

RESUMO

OBJECTIVES: To provide a quantitative synthesis of studies on the relationship between vision impairment (VI) and cognitive outcomes in older adults. METHOD: A systematic search was undertaken of relevant databases for original articles published before April 2020. Random effect models were used to obtain pooled estimates of the associations between VI and cognitive outcomes (cognitive impairment and dementia) with subgroup analyses of VI measures, cross-sectional associations of VI with cognitive impairment, and longitudinal associations of baseline VI with incident cognitive impairment and dementia. Potential sources of heterogeneity were explored by meta-regression. Publication bias was evaluated with Egger's test. RESULTS: Sixteen studies including 76,373 participants were included in this meta-analysis, with five cross-sectional studies and eleven longitudinal studies. There was a significantly increased risk of cognitive outcomes with VI identified by subjective measures (odds ratio (OR)=1.63; 95% confidence interval (CI): 1.26-1.99) and objective measures (OR = 1.59; 95% CI: 1.40-1.78). The odds of baseline cognitive impairment were 137% higher in older adults with VI compared with those without VI (OR = 2.37, 95% CI: 1.84-3.03) at baseline. Compared with older adults without VI at baseline, those with baseline VI had a higher relative risk (RR) of incident cognitive impairment (RR = 1.41; 95% CI: 1.31-1.51) and dementia (RR = 1.44, 95% CI: 1.19-1.75). CONCLUSIONS: VI was associated with increased risks of cognitive impairment and dementia across cross-sectional and longitudinal studies. Additional research and randomized clinical trials are warranted to examine the implications of treatment for VI, such as wearing glasses and cataract surgery, to avoid cognitive impairment and dementia.


Assuntos
Disfunção Cognitiva , Demência , Humanos , Idoso , Estudos Transversais , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/complicações , Risco , Demência/epidemiologia , Demência/complicações , Cognição
13.
J Gerontol Soc Work ; 66(3): 368-380, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-35855574

RESUMO

The aim of this study is to examine perceived quality of life in Chinese older adults living with cognitive impairment and explore its associations with caregivers' characteristics. Questionnaires were administered in person to 271 caregiver-care recipient dyads from urban communities in mainland China in 2019. We used the 40-item Alzheimer's Disease-related Quality of Life tool and asked caregiver respondents to indicate care recipients' life conditions. The questionnaire asked caregivers about their sociodemographic characteristics, levels of informal social support, caregiver burden, and depressive symptoms. Caregivers' higher levels of caregiver burden (ß = > -0.19, p < .01) and depressive symptoms (ß = > -0.19, p < .01) amongst caregivers were significantly associated with lower quality of life among care recipients. Informal support from relatives and friends to caregivers did not significantly affect quality of life of care recipients. The results suggested that reducing caregivers' burden and depressive symptoms are essential to promote quality of life of care recipients. Formal support from health professionals, service organizations, and communities are urgently called to promote the wellbeing of Chinese families affected by cognitive impairment.


Assuntos
Disfunção Cognitiva , Qualidade de Vida , Humanos , Idoso , População do Leste Asiático , Inquéritos e Questionários , Cuidadores/psicologia , Disfunção Cognitiva/complicações
14.
J Neurosci ; 41(16): 3588-3596, 2021 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-33707293

RESUMO

Mutations in the PRPH2 gene encoding the photoreceptor-specific protein PRPH2 (also known as peripherin-2 or rds) cause a broad range of autosomal dominant retinal diseases. Most of these mutations affect the structure of the light-sensitive photoreceptor outer segment, which is composed of a stack of flattened "disc" membranes surrounded by the plasma membrane. The outer segment is renewed on a daily basis in a process whereby new discs are added at the outer segment base and old discs are shed at the outer segment tip. New discs are formed as serial membrane evaginations, which eventually enclose through a complex process of membrane remodeling (completely in rods and partially in cones). As disc enclosure proceeds, PRPH2 localizes to the rims of enclosed discs where it forms oligomers which fortify the highly curved membrane structure of these rims. In this study, we analyzed the outer segment phenotypes of mice of both sexes bearing a single copy of either the C150S or the Y141C PRPH2 mutation known to prevent or increase the degree of PRPH2 oligomerization, respectively. Strikingly, both mutations increased the number of newly forming, not-yet-enclosed discs, indicating that the precision of disc enclosure is regulated by PRPH2 oligomerization. Without tightly controlled enclosure, discs occasionally over-elongate and form large membranous "whorls" instead of disc stacks. These data show that the defects in outer segment structure arising from abnormal PRPH2 oligomerization are manifested at the stage of disc enclosure.SIGNIFICANCE STATEMENT The light-sensitive photoreceptor outer segment contains a stack of flattened "disc" membranes that are surrounded, or "enclosed," by the outer segment membrane. Disc enclosure is an adaptation increasing photoreceptor light sensitivity by facilitating the diffusion of the second messenger along the outer segment axes. However, the molecular mechanisms by which photoreceptor discs enclose within the outer segment membrane remain poorly understood. We now demonstrate that oligomers of the photoreceptor-specific protein peripherin-2, or PRPH2, play an active role in this process. We further propose that defects in disc enclosure because of abnormal PRPH2 oligomerization result in major structural abnormalities of the outer segment, ultimately leading to loss of visual function and cell degeneration in PRPH2 mutant models and human patients.


Assuntos
Periferinas/fisiologia , Células Fotorreceptoras de Vertebrados/fisiologia , Animais , Membrana Celular/genética , Membrana Celular/ultraestrutura , Camundongos , Camundongos Endogâmicos C57BL , Mutação/genética , Células Fotorreceptoras de Vertebrados/ultraestrutura , Células Fotorreceptoras Retinianas Cones/metabolismo , Células Fotorreceptoras Retinianas Bastonetes/metabolismo , Segmento Externo da Célula Bastonete/ultraestrutura
15.
BMC Plant Biol ; 22(1): 595, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36529716

RESUMO

BACKGROUND: With the advances in the high throughput next generation sequencing technologies, genome-wide association studies (GWAS) have identified a large set of variants associated with complex phenotypic traits at a very fine scale. Despite the progress in GWAS, identification of genotype-phenotype relationship remains challenging in maize due to its nature with dozens of variants controlling the same trait. As the causal variations results in the change in expression, gene expression analyses carry a pivotal role in unraveling the transcriptional regulatory mechanisms behind the phenotypes. RESULTS: To address these challenges, we incorporated the gene expression and GWAS-driven traits to extend the knowledge of genotype-phenotype relationships and transcriptional regulatory mechanisms behind the phenotypes. We constructed a large collection of gene co-expression networks and identified more than 2 million co-expressing gene pairs in the GWAS-driven pan-network which contains all the gene-pairs in individual genomes of the nested association mapping (NAM) population. We defined four sub-categories for the pan-network: (1) core-network contains the highest represented ~ 1% of the gene-pairs, (2) near-core network contains the next highest represented 1-5% of the gene-pairs, (3) private-network contains ~ 50% of the gene pairs that are unique to individual genomes, and (4) the dispensable-network contains the remaining 50-95% of the gene-pairs in the maize pan-genome. Strikingly, the private-network contained almost all the genes in the pan-network but lacked half of the interactions. We performed gene ontology (GO) enrichment analysis for the pan-, core-, and private- networks and compared the contributions of variants overlapping with genes and promoters to the GWAS-driven pan-network. CONCLUSIONS: Gene co-expression networks revealed meaningful information about groups of co-regulated genes that play a central role in regulatory processes. Pan-network approach enabled us to visualize the global view of the gene regulatory network for the studied system that could not be well inferred by the core-network alone.


Assuntos
Estudo de Associação Genômica Ampla , Zea mays , Zea mays/genética , Estudo de Associação Genômica Ampla/métodos , Herança Multifatorial , Fenótipo , Redes Reguladoras de Genes , Polimorfismo de Nucleotídeo Único/genética
16.
Bioinformatics ; 38(1): 236-242, 2021 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-34406385

RESUMO

MOTIVATION: Over the last decade, RNA-Seq whole-genome sequencing has become a widely used method for measuring and understanding transcriptome-level changes in gene expression. Since RNA-Seq is relatively inexpensive, it can be used on multiple genomes to evaluate gene expression across many different conditions, tissues and cell types. Although many tools exist to map and compare RNA-Seq at the genomics level, few web-based tools are dedicated to making data generated for individual genomic analysis accessible and reusable at a gene-level scale for comparative analysis between genes, across different genomes and meta-analyses. RESULTS: To address this challenge, we revamped the comparative gene expression tool qTeller to take advantage of the growing number of public RNA-Seq datasets. qTeller allows users to evaluate gene expression data in a defined genomic interval and also perform two-gene comparisons across multiple user-chosen tissues. Though previously unpublished, qTeller has been cited extensively in the scientific literature, demonstrating its importance to researchers. Our new version of qTeller now supports multiple genomes for intergenomic comparisons, and includes capabilities for both mRNA and protein abundance datasets. Other new features include support for additional data formats, modernized interface and back-end database and an optimized framework for adoption by other organisms' databases. AVAILABILITY AND IMPLEMENTATION: The source code for qTeller is open-source and available through GitHub (https://github.com/Maize-Genetics-and-Genomics-Database/qTeller). A maize instance of qTeller is available at the Maize Genetics and Genomics database (MaizeGDB) (https://qteller.maizegdb.org/), where we have mapped over 200 unique datasets from GenBank across 27 maize genomes. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Genoma , Genômica , Software , Bases de Dados de Ácidos Nucleicos , Zea mays/genética , Perfilação da Expressão Gênica
17.
Artigo em Inglês | MEDLINE | ID: mdl-35460286

RESUMO

OBJECTIVES: To examine (1) the association between perceived discrimination, including everyday perceived discrimination and major lifetime perceived discrimination, and cognitive function and (2) the mediating role of depression between discrimination and cognitive function among older Puerto Ricans. METHODS: Data came from the Boston Puerto Rican Health Study, collected from 562 Puerto Ricans aged 60+. Structural Equation Modelling was used to examine the association between discrimination and cognitive function and the mediating effect of depression. RESULTS: Everyday perceived discrimination was negatively associated with cognitive function, which was fully mediated by depression. Major Lifetime perceived discrimination was not associated with cognitive function. CONCLUSIONS: The findings contribute new information regarding the impact of perceived discrimination on cognitive function among older Puerto Ricans and underscore the importance of assessing experiences of discrimination to prevent depression and cognitive decline in this population.


Assuntos
Disfunção Cognitiva , Depressão , Cognição , Depressão/psicologia , Hispânico ou Latino , Humanos , Discriminação Percebida , Porto Rico
18.
Am J Primatol ; 84(6): e23371, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35235684

RESUMO

Maintaining water balance is essential for organismal health, and lactating females must balance individual needs with milk production and offspring hydration. Primate milk is dilute and presumed to be the primary source for infant hydration for a considerable time period. Few studies have investigated the hydration burden that lactation may place on female primates. In this study, we investigated sources of variation in female and offspring drinking frequency among wild chimpanzees (Pan troglodytes). We hypothesized females would experience seasonal and lactation hydration burdens and adjust their drinking behavior to accommodate these, but this hydration burden would vary between females of different dominance ranks. We also predicted that parity would relate to maternal drinking frequency since primiparous females are still investing in their own growth. Finally, we predicted that offspring would drink more in the dry season and as they aged and lost milk as a water source, but that offspring of high-ranking females would be buffered from these effects. Using 41 years of long-term data on the behavior of mothers and offspring of Gombe National Park, we found that mothers drank more in the dry season, but there was no significant difference between mothers of different ranks during this period. Low-ranking females drank significantly more than mid- and high-ranking females during late lactation. Offspring also drank more in the dry season and as they aged, but there was no evidence of buffering for those with high-ranking mothers. While chimpanzees in our study population drank infrequently, they do demonstrate noticeable shifts in drinking behavior that suggests seasonal and reproductive hydration burdens.


Assuntos
Lactação , Pan troglodytes , Animais , Feminino , Humanos , Mães , Gravidez , Reprodução , Água
19.
Health Soc Work ; 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36473056

RESUMO

This study examined the association between depressive symptoms and self-rated health (SRH) and whether and how such association varies by education among older adults with cancer. Data came from the 2019 National Health Interview Survey. A total of 2,470 participants aged 65 or older who had been diagnosed with cancer by a doctor or other health professional were included in this study. Ordinal logistic regression was used to examine the association between depressive symptoms and SRH and whether and how such association varies by education among older adults with cancer. More depressive symptoms were associated with worse SRH. Such association became stronger with higher education among older adults with cancer. Findings confirm the associations between depressive symptoms and SRH among older adults with cancer. The differential impact of education on SRH and on the association between depressive symptoms and SRH highlights the importance of considering patients' educational attainment in a more comprehensive way when working with older adults with cancer. When conducting distress screening among cancer survivors, oncology social workers should be aware of the complex relationship between education and depression in relation to cancer survivors' SRH.

20.
J Gerontol Soc Work ; 65(6): 649-663, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34889717

RESUMO

The purpose of this study is to examine the reliability and validity of the ADRQL instrument among older adults with cognitive impairment in mainland China. Three hundred older adults with cognitive impairment and their primary family caregivers from Wuhan participated in structured interviews. Cronbach's α and Kuder-Richardson Formula 20 were used to examine internal consistency reliability. Confirmatory factor analysis, Heterotrait-Monotrait ratios, and ordinary least square regression were used to assess the factorial validity, discriminant validity, and criterion validity. The ADRQL had acceptable reliability and validity, which can be used to assess overall quality of life for this population.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Idoso , Doença de Alzheimer/complicações , China , Disfunção Cognitiva/complicações , Humanos , Psicometria , Qualidade de Vida , Reprodutibilidade dos Testes , Inquéritos e Questionários
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