Production, characterization and crystallization of the Plasmodium falciparum aquaporin.

The causative agent of malaria, Plasmodium falciparum posses a single aquaglyceroporin (PfAQP) which represents a potential drug target for treatment of the disease. PfAQP is localized to the parasite membrane to transport water, glycerol, ammonia and possibly glycolytic intermediates. In order to enable design of inhibitors we set out to determine the 3D structure of PfAQP, where the first bottleneck to overcome is achieving high enough yield of recombinant protein. The wild type PfAQP gene was expressed to low or undetectable levels in the expression hosts, Escherichia coli and Pichia pastoris, which was assumed to be due to different genomic A+T content and different codon usage. Thus, two codon-optimized PfAQP genes were generated. The Opt-PfAQP for E. coli still did not result in high production yields, possibly due to folding problems. However, PfAQP optimized for P. pastoris was successfully expressed in P. pastoris for production and in Saccharomyces cerevisiae for functional studies. In S. cerevisiae, PfAQP mediated glycerol transport but unexpectedly water transport could not be confirmed. Following high-level membrane-localized expression in P. pastoris (estimated to 64mg PfAQP per liter cell culture) PfAQP was purified to homogeneity (18mg/L) and initial attempts at crystallization of the protein yielded several different forms

radiation in

STAT1 signaling is associated with acquired crossresistance to doxorubicin an

Dysregulation of COVID-19 related gene expression in the COPD lung

Background: chronic obstructive pulmonary disease (COPD) patients are at increased risk of poor outcome from COVID-19. Early data suggest increased expression of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) receptor angiotensin converting enzyme 2 (ACE2), but relationships to disease phenotype and downstream regulators of inflammation in the Renin-Angiotensin system (RAS) are unknown. To determine the relationship between RAS gene expression relevant to SARS-CoV-2 infection in the lung and relationship to disease characteristics in COPD.Methods: we quantified gene expression using RNA sequencing of epithelial brushings and bronchial biopsies from 31 COPD and 37 control subjects.Results: ACE2 gene expression (log2-fold change (FC)) was increased in COPD compared to ex-smoking (HV-ES) controls in epithelial brushings (0.25, p=0.042) and biopsies (0.23, p=0.050), and correlated with worse lung function (r=-0.28, p=0.0090). Angiotensin converting enzyme 2 (ACE2) was further increased in frequent exacerbators compared to infrequent exacerbators (0.51, p=0.00045). Increased ACE2 expression also associated with use of ACE inhibitors (ACEi) (0.50, p=0.0034) and having cardiovascular disease (0.23, p=0.048) or hypertension (0.34, p=0.0089) and inhaled corticosteroid use in COPD subjects in biopsies (0.33, p=0.049). Angiotensin II receptor type (AGTR)1 and 2 expression was decreased in COPD biopsies compared to HV-ES controls with log2FC of –0.26 (p=0.033) and -0.40, (p=0.0010), respectively. However, the AGTR1:2 ratio was increased in COPD subjects compared with HV-ES controls, log2FC of 0.57 (p=0.0051).Conclusion: this analysis reveals the potential mechanisms driving susceptibility to SARS-CoV-2 infection and inflammation associated with severe COVID-19 seen in COPD. Extension of this approach to other viruses may lead to opportunities for therapeutic development to improve outcomes in the pandemic and beyond

A regulatory polymorphism in PDCD1 is associated with susceptibility to systemic lupus erythematosus in humans.

To access publisher full text version of this article. Please click on the hyperlink in Additional Links fieldSystemic lupus erythematosus (SLE, OMIM 152700) is a complex autoimmune disease that affects 0.05% of the Western population, predominantly women. A number of susceptibility loci for SLE have been suggested in different populations, but the nature of the susceptibility genes and mutations is yet to be identified. We previously reported a susceptibility locus (SLEB2) for Nordic multi-case families. Within this locus, the programmed cell death 1 gene (PDCD1, also called PD-1) was considered the strongest candidate for association with the disease. Here, we analyzed 2,510 individuals, including members of five independent sets of families as well as unrelated individuals affected with SLE, for single-nucleotide polymorphisms (SNPs) that we identified in PDCD1. We show that one intronic SNP in PDCD1 is associated with development of SLE in Europeans (found in 12% of affected individuals versus 5% of controls; P = 0.00001, r.r. (relative risk) = 2.6) and Mexicans (found in 7% of affected individuals versus 2% of controls; P = 0.0009, r.r. = 3.5). The associated allele of this SNP alters a binding site for the runt-related transcription factor 1 (RUNX1, also called AML1) located in an intronic enhancer, suggesting a mechanism through which it can contribute to the development of SLE in humans

Políticas para Fronteira, História e Identidade: a luta simbólica nos processos de demarcação de terras indígenas Terena

Este artigo analisa a problemática da fronteira a partir do estudo da situação dos índios Terena no Mato Grosso do Sul, localizados em aldeias de uma região de fronteira internacional. Pretendemos apresentar algumas reflexões teóricas sobre essas lutas simbólicas e também o processo de desenvolvimento da fronteira e seus efeitos sobre as sociedades indígenas. Pretendemos realizar dois movimentos analíticos: 1. a análise da luta simbólica que perpassa os processos judiciais desencadeados por conflitos territoriais entre os índios Terena e os produtores rurais, mostrando como a ideia de fronteira é ativada na construção de mecanismos políticos de exclusão e (des)legitimação de grupos étnicos; 2. a análise das políticas de Estado para a fronteira, as dinâmicas territoriais e sua confrontação com as políticas simbólicas indígenas nas diferentes situações locais na fronteira, que igualmente integram a luta simbólica por identidades reconhecidas como legítimas e territórios.<br>This article analyzes the issue of the border based on a study of the experiences of the Terena indigenous people in Mato Grosso do Sul, living in villages situated in an international border region. I present a number of theoretical reflections on these symbolic conflicts, the border development process and its effects on indigenous societies. The article contains two analytic movements: 1. an analysis of the symbolic conflict permeating the legal processes linked to the territorial conflicts between the Terena and rural producers, showing how the idea of the border is activated in the construction of political mechanisms for excluding and (de)legitimizing ethnic groups; 2. an analysis of the State's border policies, the territorial dynamics and its confrontation with the indigenous symbolic policies in the different local situations on the border, which also form part of the symbolic fight for recognition of the legitimacy of indigenous identities and territories