The Scribble and Par complexes in polarity and migration: friends or foes?

The Par complex [consisting of Bazooka (also called Par3), Par6 and aPKC] is a well-described regulator of cell polarity whose role in many aspects of cell morphogenesis is under intense investigation. Recently, another set of proteins known as the Scribble complex (consisting of Scribble, Discs large and Lethal giant larvae) has also been shown to be important in polarity regulation in several settings. Here, we describe the current status of Scribble in polarity and review evidence from various model systems that indicates an essential but context-dependent role for the Scribble and Par complexes in directed cell migration. Based on the known interactions of Scribble and Par complexes with each other and with other signalling pathways, we propose models by which Par and Scribble might interact to regulate cell migration.     

哺乳动物神经发育中的Par极性复合体

哺乳动物的神经发育过程极其复杂, 其形态结构和机能变化受到严格的调控。细胞极性是哺乳动物神经发生中最基本的特征之一, 在其调控因素中, Par极性复合体是研究最多的蛋白质。神经发育过程中Par蛋白的分布与量呈现动态变化, 影响细胞连接建立、细胞极性形成、神经突触发生及神经元迁移, 也影响到神经前体细胞的命运。文章主要从胚胎新皮层神经前体细胞及体外培养神经元角度, 总结了近年在Par极性蛋白的细胞内分布、机能及作用机制方面的研究进展。     

Par－4与阿尔茨海默病神经元凋亡

前列腺凋亡反应蛋白-4(prostate apoptosis response-4．Par-4)是一种小分子蛋白质．其生理功能尚不清楚,但能够促进多种细胞包括神经元的凋亡已得到证实。Par-4参与阿尔茨海默病(Alzheimer′s disease,AD)神经元凋亡过程复杂．且有望成为筛选治疗AD药物的作用靶点。     

Detention D′arabinofuranncwuclbdsides Par Transpdrmation Chemique De Certains Xylofurannonuclesosides

Abstract

βD-arabinofuranonucleosides have been surprisingly obtained from (3, 5-di-O-benzoyl-β-D-xylofuranosyl) nucleosides through an oxidation, followed by reduction and deacylation procedure.     

Serologically Defined Variations in Malaria Endemicity in Pará State,Brazil

Background

Measurement of malaria endemicity is typically based on vector or parasite measures. A complementary approach is the detection of parasite specific IgG antibodies. We determined the antibody levels and seroconversion rates to both P. vivax and P. falciparum merozoite antigens in individuals living in areas of varying P. vivax endemicity in Pará state, Brazilian Amazon region.

Methodology/Principal Findings

The prevalence of antibodies to recombinant antigens from P. vivax and P. falciparum was determined in 1,330 individuals. Cross sectional surveys were conducted in the north of Brazil in Anajás, Belém, Goianésia do Pará, Jacareacanga, Itaituba, Trairão, all in the Pará state, and Sucuriju, a free-malaria site in the neighboring state Amapá. Seroprevalence to any P. vivax antigens (MSP1 or AMA-1) was 52.5%, whereas 24.7% of the individuals were seropositive to any P. falciparum antigens (MSP1 or AMA-1). For P. vivax antigens, the seroconversion rates (SCR) ranged from 0.005 (Sucuriju) to 0.201 (Goianésia do Pará), and are strongly correlated to the corresponding Annual Parasite Index (API). We detected two sites with distinct characteristics: Goianésia do Pará where seroprevalence curve does not change with age, and Sucuriju where seroprevalence curve is better described by a model with two SCRs compatible with a decrease in force of infection occurred 14 years ago (from 0.069 to 0.005). For P. falciparum antigens, current SCR estimates varied from 0.002 (Belém) to 0.018 (Goianésia do Pará). We also detected a putative decrease in disease transmission occurred ∼29 years ago in Anajás, Goianésia do Pará, Itaituba, Jacareacanga, and Trairão.

Conclusions

We observed heterogeneity of serological indices across study sites with different endemicity levels and temporal changes in the force of infection in some of the sites. Our study provides further evidence that serology can be used to measure and monitor transmission of both major species of malaria parasite.     

Scrib复合物和Par复合物——从细胞极性调控到肿瘤发生

上皮细胞和组织发生癌变时,通常会伴随细胞极性丧失和组织结构紊乱的现象。然而,极性丧失对肿瘤发生的贡献却一直存在争论。随着控制上皮细胞顶-底极性分子机制的逐步揭示,人们发现,这一极性机制与肿瘤发生联系紧密。上皮细胞顶-底极性的确立主要依赖于顶膜区Par复合物与底侧膜区Scrib复合物之间的拮抗。当Scrib复合物活性下调或Par复合物活性上调时,两复合物间的这种相互制约的平衡就会被打破,从而导致肿瘤发生。本文主要综述Scrib复合物和Par复合物如何参与上皮细胞顶-底极性的建立,以及两者间的互作与肿瘤发生的关系。     

Prédisposition À L'Infection Par Trichophyton Rubrum. Investigations Biochimiques Et Fonctionelles

Sans résuméLu dans la séance du ler Congrès International de Dermatologie Tropicale, Napoli, 8–13 juin, 1964.     

A new species of Alstroemeria (Alstroemeriaceae) from Pará, Brazil

A new species,Alstroemeria paraensis, from Pará, Brazil, is described and illustrated. This species is characterized by its robust floral stem, reduced leaves, congested inflorescence, and maculated inner and outer tepals.     

Two new biting midges from Pará, Brazil (Diptera: Ceratopogonidae)

Two new species of Culicoides Latreille of the subgenus Haematomyidium Goeldi are described and illustrated based on female specimens from Pará, Brazil. The new species are compared with their similar congeners.     

Quantifying avoided deforestation in Pará: Protected areas,buffer zones and edge effects

Percentage of forests saved due to establishment of protected areas is an important piece of information for government institutions and, therefore, is the goal of this study. However, non random location selection bias makes such information directly unobservable. To overcome this problem, propensity score matching was applied. Unlike in previous studies, impact of buffer zone management was assessed by estimating avoided deforestation in buffer zones and park edges. The study area is the state of Pará. Overall results revealed that park protection saved 0.72% of protected surface from deforestation during 2000–2004 year period (∼2900 km² of forests). The highest percentage of avoided deforestation was recorded in protected areas, situated near deforestation hotspots: central part of Eastern Pará, alongside Trans-Amazonian highway and on the banks of Amazon River. The findings also suggest that buffer zones tend to reduce deforestation where pressure on forests is lower, but substitution effect takes over in areas of high deforestation pressure (since loggers are prevented from deforesting within conservation units, deforestation in surrounding areas increases). Finally, the study does not find evidence of edge effects in the state of Pará.     

Amazonian mangroves – A multidisciplinary case study in Pará State,North Brazil: Introduction

It is always a pleasant but not alwaysso easy task to write an introduction -ashort one- on the subject of Amazônia.The region is so rich in nature andculture, history and myths, that thedifficulty is to keep these aspectscompletely separated from each other, as inany interdisciplinary research.Fortunately, the layout of this edition hasleft a bit of extra space in thisintroduction for, besides the numbers andfacts, some etymology, discovery voyagesand old maps ¨.     

β1 Integrin Establishes Endothelial Cell Polarity and Arteriolar Lumen Formation via a Par3-Dependent Mechanism

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Highlights? β1 integrin deletion results in loss of endothelial polarity and vessel patency ? β1 integrin regulates cell-cell adhesion protein distribution in the endothelium ? Polarity loss is typified by decreased Par3 expression ? Par3 can partially rescue lumen formation in the β1 integrin mutant     

New Culicoides Latreille of the subgenus Mataemyia Vargas from Pará, Brazil (Diptera: Ceratopogonidae)

Two new species of Culicoides Latreille of the Neotropical subgenus Mataemyia Vargas are described and illustrated based on female specimens from Juruti, Pará, Brazil and compared with their similar congeners. This paper also presents a diagnosis of the subgenus Mataemyia and a systematic key for the identification of the 19 species of the subgenus.