Cladistic analysis of Aradidae (Insecta,Heteroptera) based on morphological and molecular characters

In this study, we present for the first time a cladistic analysis of the subfamilies of Aradidae, using molecular and morphological characters. Eighty‐three taxa, including 79 species representing eight subfamilies, are treated. The analyses were performed using 72 morphological characters and approximately 1650 bp corresponding to three molecular loci (CO1, 16S and 28S). Characters were analysed using parsimony and Bayesian methods. Based on the combined analyses, we find support for the monophyly of Aradidae, including the subfamilies Aradinae, Aneurinae, Calisiinae, Isoderminae, and Mezirinae and the paraphyly of Prosympiestinae and Chinamyersiinae. In all analyses, Prosympiestinae includes Isoderminae. The Termitaphididae were not found sister to the Aradidae in the Aradoidea.     

Structure of the Pseudorabies Virus Capsid: Comparison with Herpes Simplex Virus Type 1 and Differential Binding of Essential Minor Proteins

The structure of pseudorabies virus (PRV) capsids isolated from the nucleus of infected cells and from PRV virions was determined by cryo-electron microscopy (cryo-EM) and compared to herpes simplex virus type 1 (HSV-1) capsids. PRV capsid structures closely resemble those of HSV-1, including distribution of the capsid vertex specific component (CVSC) of HSV-1, which is a heterodimer of the pUL17 and pUL25 proteins. Occupancy of CVSC on all PRV capsids is near 100%, compared to ~ 50% reported for HSV-1 C-capsids and 25% or less that we measure for HSV-1 A- and B-capsids. A PRV mutant lacking pUL25 does not produce C-capsids and lacks visible CVSC density in the cryo-EM-based reconstruction. A reconstruction of PRV capsids in which green fluorescent protein was fused within the N-terminus of pUL25 confirmed previous studies with a similar HSV-1 capsid mutant localizing pUL25 to the CVSC density region that is distal to the penton. However, comparison of the CVSC density in a 9-Å-resolution PRV C-capsid map with the available crystal structure of HSV-1 pUL25 failed to find a satisfactory fit, suggesting either a different fold for PRV pUL25 or a capsid-bound conformation for pUL25 that does not match the X-ray model determined from protein crystallized in solution. The PRV capsid imaged within virions closely resembles C-capsids with the addition of weak but significant density shrouding the pentons that we attribute to tegument proteins. Our results demonstrate significant structure conservation between the PRV and HSV capsids.     

Do larvae evolve the same way as adults in Tingidae (Insecta: Heteroptera)?

A recent cladistic analysis showed that adult traits of Tingidae, which exhibit a great variety of shapes, evolved homoplastically from simple to complex ( Guilbert, 2001 ). These complex traits, often exaggerated, were hypothesized to be adaptive. However, this study, as well as another by Lis (1999 ), both based on adult morphology, contradict the traditional classification of Tingidae. A new analysis is performed here, that includes larval characters, which, like those of adults, have a great variety of shapes. The results corroborate the traditional classification of the Tingidae. No clear divisions among Tinginae are drawn from the analysis, but an evolutionary pattern of shapes among Tingidae emerges from this study. There is a global tendency for larval traits to evolve convergently from simple to complex, as suggested for adults. The pattern seen in adult and larval traits is independent, but consistent. These traits can be used in the same anti‐predation context, but with different roles.     

The immunostimulatory effect of T cells and T cell lymphokines on murine fetally derived placental cells

Evidence for maternal immune recognition of the fetus can be found during pregnancy, yet the conceptus remains unharmed. Indeed, in some cases immunizing the mother with cells sharing histocompatibility antigens with the fetus is beneficial to fetal survival. This could be due to the effect of maternally derived lymphokines on placental growth and function, according to the immunostimulation hypothesis. We demonstrate here that placental cells in culture proliferate upon the addition of T cell-derived lymphokines. The lymphokine activity has been separated from IL 2 and B cell growth factor, and copurified with IL 3 and granulocyte-macrophage colony-stimulating factor (CSF-GM). Recombinant CSF-GM and recombinant IL 3 showed a similar effect. The placental cells that proliferate in culture are of fetal origin and are characterized by strong adherence, phagocytosis, nonspecific esterase staining, and response to the macrophage-specific colony-stimulating factor CSF-1. In addition, treatment of pregnant females with anti-thymocyte serum as well as anti-Ly-2.1 monoclonal antibody, at gestational times before Ly-2 antigen appearance in the fetus, leads to a reduction of the proliferative and phagocytic capacity of day 12 placentae. These results clearly demonstrate that maternal T cells act upon fetally derived placental cells to improve their proliferative and phagocytic potential, and thus provide evidence for the immunostimulatory role of these cells during pregnancy.     

Pleiotropic Actions of Forskolin Result in Phosphatidylserine Exposure in Primary Trophoblasts

Forskolin is an extract of the Coleus forskholii plant that is widely used in cell physiology to raise intracellular cAMP levels. In the field of trophoblast biology, forskolin is one of the primary treatments used to induce trophoblastic cellular fusion. The syncytiotrophoblast (ST) is a continuous multinucleated cell in the human placenta that separates maternal from fetal circulations and can only expand by fusion with its stem cell, the cytotrophoblast (CT). Functional investigation of any aspect of ST physiology requires in vitro differentiation of CT and de novo ST formation, thus selecting the most appropriate differentiation agent for the hypothesis being investigated is necessary as well as addressing potential off-target effects. Previous studies, using forskolin to induce fusion in trophoblastic cell lines, identified phosphatidylserine (PS) externalization to be essential for trophoblast fusion and showed that widespread PS externalization is present even after fusion has been achieved. PS is a membrane phospholipid that is primarily localized to the inner-membrane leaflet. Externalization of PS is a hallmark of early apoptosis and is involved in cellular fusion of myocytes and macrophages. We were interested to examine whether PS externalization was also involved in primary trophoblast fusion. We show widespread PS externalization occurs after 72 hours when fusion was stimulated with forskolin, but not when stimulated with the cell permeant cAMP analog Br-cAMP. Using a forskolin analog, 1,9-dideoxyforskolin, which stimulates membrane transporters but not adenylate cyclase, we found that widespread PS externalization required both increased intracellular cAMP levels and stimulation of membrane transporters. Treatment of primary trophoblasts with Br-cAMP alone did not result in widespread PS externalization despite high levels of cellular fusion. Thus, we concluded that widespread PS externalization is independent of trophoblast fusion and, importantly, provide evidence that the common differentiation agent forskolin has previously unappreciated pleiotropic effects on trophoblastic cells.     

Arsenic Trioxide Overcomes Rapamycin-Induced Feedback Activation of AKT and ERK Signaling to Enhance the Anti-Tumor Effects in Breast Cancer

Inhibitors of the mammalian target of rapamycin (mTORi) have clinical activity; however, the benefits of mTOR inhibition by rapamycin and rapamycin-derivatives (rapalogs) may be limited by a feedback mechanism that results in AKT activation. Increased AKT activity resulting from mTOR inhibition can be a result of increased signaling via the mTOR complex, TORC2. Previously, we published that arsenic trioxide (ATO) inhibits AKT activity and in some cases, decreases AKT protein expression. Therefore, we propose that combining ATO and rapamycin may circumvent the AKT feedback loop and increase the anti-tumor effects. Using a panel of breast cancer cell lines, we find that ATO, at clinically-achievable doses, can enhance the inhibitory activity of the mTORi temsirolimus. In all cell lines, temsirolimus treatment resulted in AKT activation, which was decreased by concomitant ATO treatment only in those cell lines where ATO enhanced growth inhibition. Treatment with rapalog also results in activated ERK signaling, which is decreased with ATO co-treatment in all cell lines tested. We next tested the toxicity and efficacy of rapamycin plus ATO combination therapy in a MDA-MB-468 breast cancer xenograft model. The drug combination was well-tolerated, and rapamycin did not increase ATO-induced liver enzyme levels. In addition, combination of these drugs was significantly more effective at inhibiting tumor growth compared to individual drug treatments, which corresponded with diminished phospho-Akt and phospho-ERK levels when compared with rapamycin-treated tumors. Therefore, we propose that combining ATO and mTORi may overcome the feedback loop by decreasing activation of the MAPK and AKT signaling pathways.     

Low levels of taurine introgression in the current Brazilian Nelore and Gir indicine cattle populations

Background

Nelore and Gir are the two most important indicine cattle breeds for production of beef and milk in Brazil. Historical records state that these breeds were introduced in Brazil from the Indian subcontinent, crossed to local taurine cattle in order to quickly increase the population size, and then backcrossed to the original breeds to recover indicine adaptive and productive traits. Previous investigations based on sparse DNA markers detected taurine admixture in these breeds. High-density genome-wide analyses can provide high-resolution information on the genetic composition of current Nelore and Gir populations, estimate more precisely the levels and nature of taurine introgression, and shed light on their history and the strategies that were used to expand these breeds.

Results

We used the high-density Illumina BovineHD BeadChip with more than 777 K single nucleotide polymorphisms (SNPs) that were reduced to 697 115 after quality control filtering to investigate the structure of Nelore and Gir populations and seven other worldwide populations for comparison. Multidimensional scaling and model-based ancestry estimation clearly separated the indicine, European taurine and African taurine ancestries. The average level of taurine introgression in the autosomal genome of Nelore and Gir breeds was less than 1% but was 9% for the Brahman breed. Analyses based on the mitochondrial SNPs present in the Illumina BovineHD BeadChip did not clearly differentiate taurine and indicine haplotype groupings.

Conclusions

The low level of taurine ancestry observed for both Nelore and Gir breeds confirms the historical records of crossbreeding and supports a strong directional selection against taurine haplotypes via backcrossing. Random sampling in production herds across the country and subsequent genotyping would be useful for a more complete view of the admixture levels in the commercial Nelore and Gir populations.

Electronic supplementary material

The online version of this article (doi:10.1186/s12711-015-0109-5) contains supplementary material, which is available to authorized users.