The Drosophila Anion Exchanger (DAE) lacks a detectable interaction with the spectrin cytoskeleton

<p>Abstract</p> <p>Background</p> <p>Current models suggest that the spectrin cytoskeleton stabilizes interacting ion transport proteins at the plasma membrane. The human erythrocyte anion exchanger (AE1) was the first membrane transport protein found to be associated with the spectrin cytoskeleton. Here we evaluated a conserved anion exchanger from Drosophila (DAE) as a marker for studies of the downstream effects of spectrin cytoskeleton mutations.</p> <p>Results</p> <p>Sequence comparisons established that DAE belongs to the SLC4A1-3 subfamily of anion exchangers that includes human AE1. Striking sequence conservation was observed in the C-terminal membrane transport domain and parts of the N-terminal cytoplasmic domain, but not in the proposed ankyrin-binding site. Using an antibody raised against DAE and a recombinant transgene expressed in <it>Drosophila </it>S2 cells DAE was shown to be a 136 kd plasma membrane protein. A major site of expression was found in the stomach acid-secreting region of the larval midgut. DAE codistributed with an infolded subcompartment of the basal plasma membrane of interstitial cells. However, spectrin did not codistribute with DAE at this site or in anterior midgut cells that abundantly expressed both spectrin and DAE. Ubiquitous knockdown of DAE with dsRNA eliminated antibody staining and was lethal, indicating that DAE is an essential gene product in <it>Drosophila</it>.</p> <p>Conclusions</p> <p>Based on the lack of colocalization and the lack of sequence conservation at the ankyrin-binding site, it appears that the well-characterized interaction between AE1 and the spectrin cytoskeleton in erythrocytes is not conserved in <it>Drosophila</it>. The results establish a pattern in which most of the known interactions between the spectrin cytoskeleton and the plasma membrane in mammals do not appear to be conserved in <it>Drosophila</it>.</p

Varicellovirus UL49.5 Proteins Differentially Affect the Function of the Transporter Associated with Antigen Processing, TAP

Cytotoxic T-lymphocytes play an important role in the protection against viral infections, which they detect through the recognition of virus-derived peptides, presented in the context of MHC class I molecules at the surface of the infected cell. The transporter associated with antigen processing (TAP) plays an essential role in MHC class I–restricted antigen presentation, as TAP imports peptides into the ER, where peptide loading of MHC class I molecules takes place. In this study, the UL49.5 proteins of the varicelloviruses bovine herpesvirus 1 (BHV-1), pseudorabies virus (PRV), and equine herpesvirus 1 and 4 (EHV-1 and EHV-4) are characterized as members of a novel class of viral immune evasion proteins. These UL49.5 proteins interfere with MHC class I antigen presentation by blocking the supply of antigenic peptides through inhibition of TAP. BHV-1, PRV, and EHV-1 recombinant viruses lacking UL49.5 no longer interfere with peptide transport. Combined with the observation that the individually expressed UL49.5 proteins block TAP as well, these data indicate that UL49.5 is the viral factor that is both necessary and sufficient to abolish TAP function during productive infection by these viruses. The mechanisms through which the UL49.5 proteins of BHV-1, PRV, EHV-1, and EHV-4 block TAP exhibit surprising diversity. BHV-1 UL49.5 targets TAP for proteasomal degradation, whereas EHV-1 and EHV-4 UL49.5 interfere with the binding of ATP to TAP. In contrast, TAP stability and ATP recruitment are not affected by PRV UL49.5, although it has the capacity to arrest the peptide transporter in a translocation-incompetent state, a property shared with the BHV-1 and EHV-1 UL49.5. Taken together, these results classify the UL49.5 gene products of BHV-1, PRV, EHV-1, and EHV-4 as members of a novel family of viral immune evasion proteins, inhibiting TAP through a variety of mechanisms

Sex-Specific Growth and Reproductive Dynamics of Red Drum in the Northern Gulf of Mexico

The Red Drum Sciaenops ocellatus stock is heavily targeted in the Gulf of Mexico (GOM) by recreational fishers and supports a small commercial fishery in Mississippi. Despite their popularity, little recent work has been done to describe their life history. In this work, we describe sex‐specific growth and reproductive dynamics of Red Drum collected from the northern GOM from September 2016 through October 2017. We evaluated seven candidate growth models and found that the three‐parameter von Bertalanffy growth function (VBGF) was the best candidate length‐at‐age model. No significant difference in growth between sexes was observed with the three‐parameter VBGF, despite the female‐specific curve having a larger mean asymptotic length than the male‐specific curve. All seven candidate growth models predicted similar mean length‐at‐age estimates, and four of them exhibited significant differences in sex‐specific mean length at age, with females reaching a larger length at age than males after age 5. There was no significant difference between the sex‐specific weight‐at‐length relationships. Red Drum are batch spawners that spawn in northern GOM coastal waters during August and September. We estimated 3.7 d between spawns and 10.5 spawning events per female in 2017. Nearly 20% of fish collected during the spawning season were sexually mature but reproductively inactive, indicating the possibility of skipped spawning. The age at 50% maturity was around 3 years (length at 50% maturity = 670 mm TL) in both sexes, but fish were not spawning capable until age 4.5 (703 mm TL) in males and age 5.8 (840 mm TL) in females. Furthermore, elevated gonadosomatic indices were not observed until around age 5–6. The updated life history information presented in this work helps to address current data limitations and provides critical information for future assessments of Red Drum stocks in the northern GOM

A Wide Extent of Inter-Strain Diversity in Virulent and Vaccine Strains of Alphaherpesviruses

Alphaherpesviruses are widespread in the human population, and include herpes simplex virus 1 (HSV-1) and 2, and varicella zoster virus (VZV). These viral pathogens cause epithelial lesions, and then infect the nervous system to cause lifelong latency, reactivation, and spread. A related veterinary herpesvirus, pseudorabies (PRV), causes similar disease in livestock that result in significant economic losses. Vaccines developed for VZV and PRV serve as useful models for the development of an HSV-1 vaccine. We present full genome sequence comparisons of the PRV vaccine strain Bartha, and two virulent PRV isolates, Kaplan and Becker. These genome sequences were determined by high-throughput sequencing and assembly, and present new insights into the attenuation of a mammalian alphaherpesvirus vaccine strain. We find many previously unknown coding differences between PRV Bartha and the virulent strains, including changes to the fusion proteins gH and gB, and over forty other viral proteins. Inter-strain variation in PRV protein sequences is much closer to levels previously observed for HSV-1 than for the highly stable VZV proteome. Almost 20% of the PRV genome contains tandem short sequence repeats (SSRs), a class of nucleic acids motifs whose length-variation has been associated with changes in DNA binding site efficiency, transcriptional regulation, and protein interactions. We find SSRs throughout the herpesvirus family, and provide the first global characterization of SSRs in viruses, both within and between strains. We find SSR length variation between different isolates of PRV and HSV-1, which may provide a new mechanism for phenotypic variation between strains. Finally, we detected a small number of polymorphic bases within each plaque-purified PRV strain, and we characterize the effect of passage and plaque-purification on these polymorphisms. These data add to growing evidence that even plaque-purified stocks of stable DNA viruses exhibit limited sequence heterogeneity, which likely seeds future strain evolution

Сетевая система контроля технологического процесса выращивания полупроводниковых кристаллов и тонких пленок

Экспериментальное моделирование аппаратно-программного обеспечения показало достаточную надежность работы системы и значительное уменьшение трудоемкости контроля и управления параметрами технологического процесса

Intrathecal immunoreactivity in people with or without previous infectious mononucleosis

OBJECTIVES: The risk of developing multiple sclerosis (MS) increases (OR: 3.1) after infectious mononucleosis (IM). However, the nature of this link is obscure. We tested the hypothesis that IM might incur long-term sequelae, including low-key inflammatory activity, with characteristics of an MS endophenotype (or presymptomatic trait), and that assays of MS-relevant cyto-/chemokines in the cerebrospinal fluid (CSF) post IM may show a trend in this direction. MATERIALS AND METHODS: We selected seven CSF cytokines (IL-1b, IL-6, YKL-40, TNF-alpha) or chemokines (IL-8, CCL2, IP-10), representing pro-inflammatory factors previously associated with MS. We assayed the CSF levels of these seven cyto-/chemokines in healthy individuals with a median follow-up time of 10 years after serologically confirmed IM (post-IM group, n=22), and in healthy controls without a history of IM (n=19). A group of MS patients (n=23) were included as reference. RESULTS: The CSF levels of IP-10, YKL-40 and CCL-2 were higher in the post-IM group than in our IM unexposed controls (p = 0.021, 0.049, 0.028). Seven of seven cyto/chemokine assays showed a trend in the predicted direction (p of binomial ratio = 0.008). However, this trend was non-significant in a multivariate test (p = 0.22). A power analysis indicated that similar studies including a larger cohort would be numerically realistic. CONCLUSIONS: These results do not reject the hypothesis that the established epidemiological association between IM and MS results from a stepwise inflammatory propagation from IM sequele to an MS endophenotype (or presymptomatic trait) in a proportion of IM patients, pending confirmation with adequate power