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21.
Ruggero Vigliaturo Alessandra Marengo Erica Bittarello Ileana Prez‐Rodríguez Goran Drai Reto Gier 《Geobiology》2020,18(5):606-618
Neutrophilic, microaerobic Fe(II)‐oxidizing bacteria (FeOB) from marine and freshwater environments are known to generate twisted ribbon‐like organo‐mineral stalks. These structures, which are extracellularly precipitated, are susceptible to chemical influences in the environment once synthesized. In this paper, we characterize the minerals associated with freshwater FeOB stalks in order to evaluate key organo‐mineral mechanisms involved in biomineral formation. Micro‐Raman spectroscopy and Field Emission Scanning Electron Microscopy revealed that FeOB isolated from drinking water wells in Sweden produced stalks with ferrihydrite, lepidocrocite and goethite as main mineral components. Based on our observations made by micro‐Raman Spectroscopy, field emission scanning electron microscopy and scanning transmission electron microscope combined with electron energy‐loss spectroscopy, we propose a model that describes the crystal‐growth mechanism, the Fe‐oxidation state, and the mineralogical state of the stalks, as well as the biogenic contribution to these features. Our study suggests that the main crystal‐growth mechanism in stalks includes nanoparticle aggregation and dissolution/re‐precipitation reactions, which are dominant near the organic exopolymeric material produced by the microorganism and in the peripheral region of the stalk, respectively. 相似文献
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Male infertility is becoming a rapidly growing problem around the world, mainly in the highly developed countries. Seminal proteome composition seems to be one of the crucial factors of the proper course of fertilization ‐ clusterin (CLU) is among the most important ones. CLU, as one of the crucial seminal plasma glycoproteins, plays a very important role in sperm capacitation and immune tolerance in the female reproductive tract. CLU is also known as a sensitive marker of oxidative stress. It has six n ‐glycosylation sites and also exhibits chaperone activity. An analysis of changes in the profile and degree of CLU glycosylation may shed some new light on the molecular mechanisms of the fertilization process and may be used as an additional diagnostic marker of male fertility. This study constitutes a review of the recently available literature concerning human seminal CLU, including changes in its glycosylation, analyzed in the context of human reproduction. 相似文献
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Davide Marzi Patrizia Brunetti Giovanni Mele Nadia Napoli Lorenzo Cal Erica Spaziani Minami Matsui Simone De Panfilis Paolo Costantino Giovanna Serino Maura Cardarelli 《The Plant journal : for cell and molecular biology》2020,103(1):379-394
In Arabidopsis, stamen elongation, which ensures male fertility, is controlled by the auxin response factor ARF8, which regulates the expression of the auxin repressor IAA19. Here, we uncover a role for light in controlling stamen elongation. By an extensive genetic and molecular analysis we show that the repressor of light signaling COP1, through its targets HY5 and HYH, controls stamen elongation, and that HY5 – oppositely to ARF8 – directly represses the expression of IAA19 in stamens. In addition, we show that in closed flower buds, when light is shielded by sepals and petals, the blue light receptors CRY1/CRY2 repress stamen elongation. Coherently, at flower disclosure and in subsequent stages, stamen elongation is repressed by the red and far‐red light receptors PHYA/PHYB. In conclusion, different light qualities – sequentially perceived by specific photoreceptors – and the downstream COP1–HY5/HYH module finely tune auxin‐induced stamen elongation and thus male fertility. 相似文献
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Noe Fernandez‐Pozo Fabian B. Haas Rabea Meyberg Kristian K. Ullrich Manuel Hiss Pierre‐Franois Perroud Sebastian Hanke Viktor Kratz Adrian F. Powell Eleanor F. Vesty Christopher G. Daum Matthew Zane Anna Lipzen Avinash Sreedasyam Jane Grimwood Juliet C. Coates Kerrie Barry Jeremy Schmutz Lukas A. Mueller Stefan A. Rensing 《The Plant journal : for cell and molecular biology》2020,102(1):165-177
Physcomitrella patens is a bryophyte model plant that is often used to study plant evolution and development. Its resources are of great importance for comparative genomics and evo‐devo approaches. However, expression data from Physcomitrella patens were so far generated using different gene annotation versions and three different platforms: CombiMatrix and NimbleGen expression microarrays and RNA sequencing. The currently available P. patens expression data are distributed across three tools with different visualization methods to access the data. Here, we introduce an interactive expression atlas, Physcomitrella Expression Atlas Tool (PEATmoss), that unifies publicly available expression data for P. patens and provides multiple visualization methods to query the data in a single web‐based tool. Moreover, PEATmoss includes 35 expression experiments not previously available in any other expression atlas. To facilitate gene expression queries across different gene annotation versions, and to access P. patens annotations and related resources, a lookup database and web tool linked to PEATmoss was implemented. PEATmoss can be accessed at https://peatmoss.online.uni-marburg.de 相似文献
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Kai Lindström Jonathan Havenhand Erica Leder Sofie Schöld Ola Svensson Charlotta Kvarnemo 《Journal of fish biology》2021,99(2):607-613
In externally fertilizing species, the gametes of both males and females are exposed to the influences of the environment into which they are released. Sperm are sensitive to abiotic factors such as salinity, but they are also affected by biotic factors such as sperm competition. In this study, the authors compared the performance of sperm of three goby species, the painted goby, Pomatoschistus pictus, the two-spotted goby, Pomatoschistus flavescens, and the sand goby, Pomatoschistus minutus. These species differ in their distributions, with painted goby having the narrowest salinity range and sand goby the widest. Moreover, data from paternity show that the two-spotted goby experiences the least sperm competition, whereas in the sand goby sperm competition is ubiquitous. The authors took sperm samples from dissected males and exposed them to high salinity water (31 PSU) representing the North Sea and low salinity water (6 PSU) representing the brackish Baltic Sea Proper. They then used computer-assisted sperm analysis to measure the proportion of motile sperm and sperm swimming speed 10 min and 20 h after sperm activation. The authors found that sperm performance depended on salinity, but there seemed to be no relationship to the species' geographical distribution in relation to salinity range. The species differed in the proportion of motile sperm, but there was no significant decrease in sperm motility during 20 h. The sand goby was the only species with motile sperm after 72 h. 相似文献
28.
Transcriptomic Profiling of Human Pluripotent Stem Cell-derived Retinal Pigment Epithelium over Time
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Marilisa Villano Annalisa Borghini Mirko Manetti Erica Gabbrielli Antonella Rossi Piersante Sestini Anna Franca Milia Francesca Nacci Serena Guiducci Marco Matucci-Cerinic Lidia Ibba-Manneschi Elisabetta Weber 《Arthritis research & therapy》2013,15(4):R90