Efficient chromosome segregation during mitosis relies on the coordinated activity of molecular motors with proteins that regulate kinetochore attachments to dynamic spindle microtubules
1. CLASPs ...are conserved kinetochore- and microtubule-associated proteins encoded by two paralog genes,
clasp1 and
clasp2, and have been previously implicated in the regulation of kinetochore microtubule dynamics
2–4. However, it remains unknown how CLASPs work in concert with other proteins to form a functional kinetochore microtubule interface. Here we have identified mitotic interactors of human CLASP1 via a proteomic approach. Among these, the microtubule plus-end-directed motor CENP-E
5 was found to form a complex with CLASP1 that colocalizes to multiple structures of the mitotic apparatus in human cells. We found that CENP-E recruits both CLASP1 and CLASP2 to kinetochores independently of its motor activity or the presence of microtubules. Depletion of CLASPs or CENP-E by RNA interference in human cells causes a significant and comparable reduction of kinetochore microtubule poleward flux and turnover rates and rescues spindle bipolarity in Kif2a-depleted cells. We conclude that CENP-E integrates two critical functions that are important for accurate chromosome movement and spindle architecture: one relying directly on its motor activity, and the other involving the targeting of key microtubule regulators to kinetochores.
Zika virus (ZIKV) infection during pregnancy can cause a set of severe abnormalities in the fetus known as congenital Zika syndrome (CZS). Experiments with animal models and in vitro systems have ...substantially contributed to our understanding of the pathophysiology of ZIKV infection. Here, to investigate the molecular basis of CZS in humans, we used a systems biology approach to integrate transcriptomic, proteomic, and genomic data from the postmortem brains of neonates with CZS. We observed that collagens were greatly reduced in expression in CZS brains at both the RNA and protein levels and that neonates with CZS had several single-nucleotide polymorphisms in collagen-encoding genes that are associated with osteogenesis imperfecta and arthrogryposis. These findings were validated by immunohistochemistry and comparative analysis of collagen abundance in ZIKV-infected and uninfected samples. In addition, we showed a ZIKV-dependent increase in the expression of cell adhesion factors that are essential for neurite outgrowth and axon guidance, findings that are consistent with the neuronal migration defects observed in CZS. Together, these findings provide insights into the underlying molecular alterations in the ZIKV-infected brain and reveal host genes associated with CZS susceptibility.
To verify the existence of a relationship between presence of off-flavor and microorganism load in quality control rejected samples of expressed human milk from a donor milk bank.
A total of 30 ...samples of expressed human milk with off-flavor were tested for the occurrence of the following microorganisms: aerobic mesophilic, psycrotrophic, proteolytic, psycrotrophic proteolytic, thermoduric, psycrotrophic thermoduric, lactate and lipolytic bacteria, molds and yeasts and Staphylococcus aureus, total coliforms and thermophilic coliforms, in accordance with official methods.
Percentage occurrence of microorganisms was as follows: aerobic mesophilic = 80%; psycrotrophic = 36.7%; proteolytic = 46.7%; psycrotrophic proteolytic = 16.7%; thermoduric = 6.7%; psycrotrophic thermoduric = 0%; lactate bacteria = 50%; lipolytic = 10%; molds and yeasts = 6.7%; S. aureus = 30%; total coliforms = 53.3%; and thermophilic coliforms = 16.7%.
A consistent relationship between presence of off-flavor and elevated microorganism counting was observed in the analyzed samples. This correlation highlights the importance of off-flavor research during selection and quality control processes in human milk banks.
ABSTRACT The objective of this study was to evaluate ozone saturation and decomposition kinetics in porous medium containing grains of different hybrids of maize. The following hybrids were used: ...common maize hybrid AG 1051, super sweet maize hybrids Tropical Plus, GSS 42072, GSS 41499 and GSS 41243. 1 kg grain samples with water contents of 13.0% (w.b.) were placed in glass containers with 3.25 L capacity. The grains were ozonized at the concentration of 1.28 mg L-1, at 25 ºC, with gas flow rate of 5.0 L min-1. Saturation time and concentration, half-life time and physical properties such as apparent specific weight, actual specific weight, porosity, sphericity and circularity of each maize hybrid were determined. The experiments were conducted in a completely randomized design with three replicates, using regression analysis of the data. Ozone saturation times remained between 6.6 and 163.9 min, with saturation concentration varying from 0.34 to 1.12 mg L-1. As for the ozone half-life time, the highest value was 10.5 min for the common maize hybrid AG 1051 and the lowest value was 0.14 min for the super sweet maize hybrid GSS 41499. It was concluded that ozone saturation and decomposition kinetics in maize depends on the hybrid contained in the porous medium. Ozone decomposition is faster in porous medium containing super sweet maize hybrids compared with the common maize hybrid.
RESUMO Objetivou-se neste estudo avaliar a saturação e a cinética de decomposição do ozônio em meio poroso contendo grãos de diferentes híbridos de milho. Foram utilizados híbridos de milho comum, AG 1051, e os de milho super doce, Tropical Plus, GSS 42072, GSS 41499 e GSS 41243. Foram usadas amostras de 1 kg de milho, com teores de água de 13,0% (b.u.), acondicionadas em recipientes de vidro com capacidade de 3,25 L. Os grãos foram ozonizados na concentração de 1,28 mg L-1, a 25 ºC e vazão do gás de 5,0 L min-1. Foram determinados o tempo e a concentração de saturação, o tempo de meia-vida, e as propriedades físicas massa específica aparente, massa específica real, porosidade, esfericidade e circularidade de cada um dos híbridos. O experimento foi realizado com delineamento experimental inteiramente casualizado, com três repetições, utilizando-se análise de regressão dos dados. No que se refere ao tempo de saturação do gás, os valores obtidos permaneceram entre 6,6 e 163,9 min, com concentração de saturação variando de 0,34 a 1,12 mg L-1. Quanto ao tempo de meia-vida do ozônio, o maior valor obtido foi 10,5 min para o híbrido de milho comum AG 1051 e o menor valor 0,16 min, para o híbrido de milho super doce GSS 41499. Verificou-se que a saturação e cinética de decomposição do ozônio em milho é dependente do híbrido contido no meio poroso. A decomposição do ozônio é mais rápida em meio poroso contendo híbridos de milho super doce.
Genetically modified (GM) crops is considered the fastest adopted crop technology in the history of modern agriculture. However, possible undesirable and unintended effects must be considered during ...the research steps toward development of a commercial product. In this report we evaluated effects of a common bean virus resistant line on arthropod populations, considered as non-target organisms. This GM bean line (named M1/4) was modified for resistance against Bean golden mosaic virus (BGMV) by expressing a mutated REP protein, which is essential for virus replication. Biosafety studies were performed for a period of three years under field conditions. The abundance of some species was significantly higher in specific treatments in a particular year, but not consistently different in other years. A regular pattern was not observed in the distribution of insects between genetically modified and conventional treatments. Data analyses showed that minor differences observed can be attributed to random variation and were not consistent enough to conclude that the treatments were different. Therefore the present study indicates that the relative abundance of species are similar in transgenic and non-transgenic fields.
Abstract
The evolution of obligate ectoparasitism in blowflies (Diptera: Calliphoridae) has intrigued scientists for over a century, and surprisingly, the genetics underlying this lifestyle remain ...largely unknown. Blowflies use odors to locate food and oviposition sites; therefore, olfaction might have played a central role in niche specialization within the group. In insects, the coreceptor
Orco
is a required partner for all odorant receptors (ORs), a major gene family involved in olfactory-evoked behaviors. Hence, we characterized the
Orco
gene in the New World screwworm,
Cochliomyia hominivorax
, a blowfly that is an obligate ectoparasite of warm-blooded animals. In contrast, most of the closely related blowflies are scavengers that lay their eggs on dead animals. We show that the screwworm
Orco
orthologue (
ChomOrco
) is highly conserved within Diptera, showing signals of strong purifying selection. Expression of
ChomOrco
is broadly detectable in chemosensory appendages, and is related to morphological, developmental, and behavioral aspects of the screwworm biology. We used CRISPR/Cas9 to disrupt
ChomOrco
and evaluate the consequences of losing the OR function on screwworm behavior. In two-choice assays,
Orco
mutants displayed an impaired response to floral-like and animal host-associated odors, suggesting that OR-mediated olfaction is involved in foraging and host-seeking behaviors in
C
.
hominivorax
. These results broaden our understanding of the chemoreception basis of niche occupancy by blowflies.
Starter cultures are defined as selected microbial preparations used to increase the efficiency of fermentation processes. In the food industry, numerous microbial cultures are used to ensure the ...production of safe and high-quality commodities. This review provides a comprehensive theoretical guide for selecting microbial cultures for use in the manufacturing of industrially important food commodities, including dairy, meat, vegetables, alcoholic beverages, cocoa, coffee, vinegar, and soy-based products. Related topics on fermented food classification, microbial domestication, and regulatory requirements are addressed. The strategies reported in this review are useful to help researchers choose methods and criteria selection.
Efforts to describe toxins from the two major families of venomous snakes (Viperidae and Elapidae) usually reveal proteins belonging to few structural types, particular of each family. Here we ...carried on an effort to determine uncommon cDNAs that represent possible new toxins from Lachesis muta (Viperidae). In addition to nine classes of typical toxins, atypical molecules never observed in the hundreds of Viperidae snakes studied so far are highly expressed: a diverging C-type lectin that is related to Viperidae toxins but appears to be independently originated; an ohanin-like toxin, which would be the third member of the most recently described class of Elapidae toxins, related to human butyrophilin and B30.2 proteins; and a 3FTx-like toxin, a new member of the widely studied three-finger family of proteins, which includes major Elapidae neurotoxins and CD59 antigen. The presence of these common and uncommon molecules suggests that the repertoire of toxins could be more conserved between families than has been considered, and their features indicate a dynamic process of venom evolution through molecular mechanisms, such as multiple recruitments of important scaffolds and domain exchange between paralogs, always keeping a minimalist nature in most toxin structures in opposition to their nontoxin counterparts.
Phoneutria nigriventer is one of the largest existing true spiders and one of the few considered medically relevant. Its venom contains several neurotoxic peptides that act on different ion channels ...and chemical receptors of vertebrates and invertebrates. Some of these venom toxins have been shown as promising models for pharmaceutical or biotechnological use. However, the large diversity and the predominance of low molecular weight toxins in this venom have hampered the identification and deep investigation of the less abundant toxins and the proteins with high molecular weight. Here, we combined conventional and next-generation cDNA sequencing with Multidimensional Protein Identification Technology (MudPIT), to obtain an in-depth panorama of the composition of P. nigriventer spider venom. The results from these three approaches showed that cysteine-rich peptide toxins are the most abundant components in this venom and most of them contain the Inhibitor Cysteine Knot (ICK) structural motif. Ninety-eight sequences corresponding to cysteine-rich peptide toxins were identified by the three methodologies and many of them were considered as putative novel toxins, due to the low similarity to previously described toxins. Furthermore, using next-generation sequencing we identified families of several other classes of toxins, including CAPs (Cysteine Rich Secretory Protein-CRiSP, antigen 5 and Pathogenesis-Related 1-PR-1), serine proteinases, TCTPs (translationally controlled tumor proteins), proteinase inhibitors, metalloproteinases and hyaluronidases, which have been poorly described for this venom. This study provides an overview of the molecular diversity of P. nigriventer venom, revealing several novel components and providing a better basis to understand its toxicity and pharmacological activities.
Blowflies and houseflies are mechanical vectors inhabiting synanthropic environments around the world. They feed and breed in fecal and decaying organic matter, but the microbiome they harbour and ...transport is largely uncharacterized. We sampled 116 individual houseflies and blowflies from varying habitats on three continents and subjected them to high-coverage, whole-genome shotgun sequencing. This allowed for genomic and metagenomic analyses of the host-associated microbiome at the species level. Both fly host species segregate based on principal coordinate analysis of their microbial communities, but they also show an overlapping core microbiome. Legs and wings displayed the largest microbial diversity and were shown to be an important route for microbial dispersion. The environmental sequencing approach presented here detected a stochastic distribution of human pathogens, such as Helicobacter pylori, thereby demonstrating the potential of flies as proxies for environmental and public health surveillance.
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