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Ethylene is synthesized from the non-proteinogenic amino acid ACC. Here, Mou et al. show that ACC itself acts independently of ethylene to trigger secretion of a pollen tube attractant in the sporophytic tissue of Arabidopsis ovules and can activate Ca2+-currents via GLUTAMATE RECEPTOR-LIKE channels.

Cytosolic ion gradients in growing pollen tubes are thought to be required for polar growth. Here the authors show that the Arabidopsis plasma membrane H+ ATPases, AHA6, AHA8, and AHA9, maintain tip-to-shank proton gradients, oscillations in cytosolic pH and actin organization to enable pollen tube elongation.

O presente trabalho propõe tomar em consideração a componente afetiva na construção identitária individual e coletiva. São formulados os conceitos de identidade afetivizada (a assunção sentimental de elementos identitários: o elemento identitário gera afetividade) e afetividade identitária (o resultado numa identidade a partir dum elemento ou duns elementos mediadores não necessariamente vinculados de modo linear com o objeto da identificação). Aplica-se em concreto à questão ortográfica no caso galego e como essas componentes podem incidir nas elaborações afetivas das pessoas em relação à conceção da língua, à literatura e aos afetos e orientações de leitura; e como essas orientações se relacionam com o próprio conceito de nação e das suas relações externas.

This study provides the easternmost record of Molossops temminckii (Burmeister 1854), and the first for the state of Paraíba, northeastern Brazil. These records were based on the capture of six specimens, three males and three females. The morphometric data and morphological characters were consistent with those described in the literature. This record extends the distributional range of the species approximately 470 km eastwards.

Objective: To assess the oral shedding and viremia of Epstein–Barr virus (EBV) in HIV‐positive patients and their relationship with oral hairy leukoplakia (OHL). Methodology: A total of 94 HIV‐positive patients were included in the study, in which blood and saliva samples were collected for EBV quantification. Data on gender, age, time of HIV seropositivity, combined antiretroviral therapy (cART), CD4+ T‐cell counts, and HIV viral load were collected. OHL diagnosis was based on histopathological examination and EBV in situ hybridization. Results: The EBV load in the 94 HIV‐positive patients was higher in saliva than in blood (2.4 and 1.6, respectively), and there was a positive correlation between EBV oral shedding and viremia (p = 0.001). Twenty (21.27%) patients had OHL and also a higher EBV load in saliva (mean log10 = 3.11) compared to those who had no OHL (p = 0.045). Presence of OHL was only associated with age (p = 0.030). Conclusion: In HIV‐positive patients, the presence of OHL was associated with EBV oral shedding but not with viremia, regardless of the amount of circulating CD4+ T cells. [ABSTRACT FROM AUTHOR]

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To evaluate the viral load of the Epstein-Barr virus (EBV) in the blood and saliva of patients positive for human immunodeficiency virus (HIV) and its relationship with oral hairy leukoplakia (OHL). A cross-sectional observational study including 94 individuals with HIV undergoing clinical examination and collection of blood samples (for analysis of HIV and EBV viremia and CD4+ T lymphocyte count) and saliva (for analysis of EBV salivary elimination). Histopathologic examination and in situ hybridization were used in the 20 confirmed cases of OHL. The majority of the sample was male (72.3%), with a mean age of 45.2 years. The average CD4+ T lymphocyte count was 535.9 cells/mm3, the majority with an undetectable HIV viral load (79.7%). The average log10 of the EBV viral load in the blood was 1.6 and in saliva it was 2.4, with a positive correlation (P =.001). Individuals with OHL had a higher viral load of EBV in their saliva (P =.045). The increase in the EBV viral load in the saliva of individuals with HIV with OHL is justified by the tropism of this virus by the epithelial cells and by the local immunological microenvironment. [ABSTRACT FROM AUTHOR]

Summary. Along the past recent years, two-photon excitation (TPE) microscopy has moved from the realms of technical curiosity to be a standard application in many advanced cell biology laboratories. The growing body of literature covered in this review points out the obvious advantages of TPE over any other imaging method based on fluorescence, clearly improving signal-to-noise ratio and thick-tissue penetration and showing added potential for vital imaging. Like any new technology that has to gain its own space, TPE microscopy is still going through the growing pains in which reproducible protocols, probes, and applications are scarce. Yet, the published reports and unpublished results covered in this review point out that TPE can eventually accommodate most available protocols and probes, most of the times with evident advantages. Further, the potential for plant sciences is obvious, as plant cells possess many absorbing molecules and structures and are routinely more opaque than tissues of other organisms. Since prices make it one of the most expensive microscopies, TPE is coming slow to be a generalised technology, but enough data are emerging to establish it as a method with no alternative for some objectives. [ABSTRACT FROM AUTHOR]

: Background Pollen is the male gametophyte of higher plants. Upon pollination, it germinates and develops into a fast-growing cytoplasmic extension, the pollen tube, which ultimately delivers the sperm into the ovary. The biological relevance of its role, and the uniqueness of this kind of cellular organization, have made pollen the focus of many approaches, and it stands today as one of the best-known models in plant cell biology. In contrast, the genetic background of its development has been until recently largely unknown. Some genes involved have been described and a few functional mutants have been characterized, but only to a limited extent and allowing only a limited understanding of the regulatory mechanisms. Yet, being a relatively simple organ (2 or 3 cells), pollen stands as an excellent target for molecular-biology-based approaches. : Recent Progress Recent studies on Arabidopsis thaliana have characterized the transcriptional profile of pollen grains and microgametogenesis in comparison to sporophytic tissues. They underline the unique characteristics of pollen, not only in terms of a strongly reduced set of genes being expressed, but also in terms of the functions of the proteins encoded and the pathways they are involved in. These approaches have expanded the number of genes with known expression in pollen from a few hundred to nearly eight thousand. While for the first time allowing systems and/or gene-family approaches, this information also expands dramatically the possibility of hypothesis-driven experimentation based on specific gene function predictions. Recent studies reveal this to be the case in, for example, transcriptional regulation, cell-cycle progression and gene-silencing mechanisms in mature pollen. [ABSTRACT FROM AUTHOR]