Chauliops fallax Scott, 1874 (Hemiptera: Heteroptera: Malcidae: Chauliopinae) is one of the most destructive insect pests of soybean and rice fields in Asia. Here we sequenced the complete mitochondrial genome of this pest. This genome is 15,739 bp long, with an A+T content of 73.7%, containing 37 typical animal mitochondrial genes and a control region. All genes were arranged in the same order as most of other Heteroptera. A remarkable strand bias was found for all nine protein coding genes (PCGs) encoded by the majority strand were positive AT-skew and negative GC-skew, whereas the reverse were found in the remaining four PCGs encoded by the minority strand and two rRNA genes. The models of secondary structures for the two rRNA genes of sequenced true bugs and Lygaeoidea were predicted. 16S rRNA consisted of six domains (domain III is absent as in other known arthropod mitochondrial genomes) and 45 helices, while three domains and 27 helices for 12S rRNA. The control region consists of five subregions: a microsatellite-like region, a tandem repeats region and other three motifs. The unusual intergenic spacer between tRNA-H and ND4 only found in the species of Lygaeoidea, not in other heteropteran species, may be the synapomorphy of this superfamily. Phylogenetic analyses were carried out based on all the 13 PCGs showed that Chauliopinae was the sister group of Malcinae and the monophyly of Lygaeoidea.

BackgroundSeveral studies have focused on cold tolerance in multiple regulated levels. However, a genome-scale molecular analysis of the regulated network under the control of transcription factors (TFs) is still lacking, especially for trees. To comprehensively identify the TFs that regulate cold stress response in the paper mulberry and understand their regulatory interactions, transcriptomic data was used to assess changes in gene expression induced by exposure to cold.ResultsResults indicated that 794 TFs, belonging to 47 families and comprising more than 59% of the total TFs of this plant, were involved in the cold stress response. They were clustered into three groups, namely early, intermediate and late responsive groups which contained 95, 550 and 149 TFs, respectively. Among of these differentially expressed TFs, one bHLH, two ERFs and three CAMTAs were considered to be the key TFs functioning in the primary signal transduction. After that, at the intermediate stage of cold stress, there were mainly two biological processes that were regulated by TFs, namely cold stress resistance (including 5 bHLH, 14 ERFs, one HSF, 4 MYBs, 3 NACs, 11 WRKYs and so on) and growth and development of lateral organ or apical meristem (including ARR-B, B3, 5 bHLHs, 2 C2H2, 4 CO-like, 2 ERF, 3 HD-ZIP, 3 YABBYs, G2-like, GATA, GRAS and TCP). In late responsive group, 3 ARR-B, C3H, 6 CO-like, 2 G2-like, 2 HSFs, 2 NACs and TCP. Most of them presented the up-regulated expression at 12 or 24 hours after cold stress implied their important roles for the new growth homeostasis under cold stress.ConclusionsOur study identified the key TFs that function in the regulatory cascades mediating the activation of downstream genes during cold tress tolerance in the paper mulberry. Based on the analysis, we found that the AP2/ERF, bHLH, MYB, NAC and WRKY families might play the central and significant roles during cold stress response in the paper mulberry just as in other species. Meanwhile, many other TF families previously reported as involving in regulation of growth and development, including ARF, DBB, G2-like, GRF, GRAS, LBD, WOX and YAABY exhibited their important potential function in growth regulation under cold stress.Electronic supplementary materialThe online version of this article (doi:10.1186/s12870-015-0489-2) contains supplementary material, which is available to authorized users.

We had previously reported that tetramethyl-O-NGDA (M4N), a synthetic derivative of the naturally occurring nordihydroguaiaretic acid (NDGA), is able to inhibit HIV Tat transactivation by blocking host Sp1 protein at the Sp1 cognate binding site on the HIV LTR promoter. The present studies were undertaken to examine whether M4N is able to inhibit the replication of herpes simplex virus (HSV), another Sp1-regulated virus. The results showed that in Vero cells, M4N inhibits at micromolar levels (IC50 = 43.5 microM) the expression of the herpes immediate early gene (alpha-ICP4), which is essential for HSV replication. An electrophoretic mobility shift assay, examining Sp1 binding to the alpha-ICP4 promoter, showed a significant inhibition of the control bands: 88% inhibition of the fast moving band (FMB) and 45% of the slow moving band (SMB), at 100 microM of drug concentration. Comparative studies between M4N and acycloguanosine (acyclovir, ACV) in cultured Vero cells revealed an interesting pattern in the drug sensitivity (IC50) and cytotoxicity (TC50) parameters. For M4N, the IC50 varied between 11.7 and 4 microM in 10 passages of HSV-1 and 4 passages of HSV-2 with no indication for a requirement of higher drug concentration. In contrast, for acyclovir, the IC50 increased from 7 microM in the first passage to 444 microM in the tenth passage of HSV-1, and >88 microM for the fourth passage of HSV-2, indicating a rapid build-up of drug resistance against acyclovir. While the selective index (SI), defined as the ratio: TC50/IC50, remained relatively constant for M4N; it dropped 60-fold for acyclovir in the endpoints of viral passages. Drug sensitivity for M4N toward the acyclovir-sensitive strain (sm44) and the acyclovir-resistant strain (ACV-10) of HSV-1 was similar, indicating no cross-resistance between M4N and acyclovir in their anti-HSV effects. These results may have an important clinical relevance since HSV has been shown to be a factor for spreading of HIV.

Cystic fibrosis (CF) is the most common lethal autosomal recessive disease in the Caucasian population. It is due to mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. To date, over 1910 mutations have been identified in the CFTR gene. Among these mutations, the CF-causing missense mutation G551D-CFTR (approx. 5% of cases) encodes for a CFTR chloride channel with normal expression on the cell surface. Nevertheless, it is associated with severe disease due to its altered channel activation. The aim of the present study was to identify specific interacting proteins of G551D-CFTR. Co-immunoprecipitated proteins with G551D-CFTR were resolved by 2D-gel electrophoresis (2-DE). Mass Spectrometry revealed that calumenin was present in the protein complex linked to G551D-CFTR. Despite its basal expression was not modified in G551D-CFTR expressing cells when compared to Wt-CFTR expressing cells, it was more abundant in the G551D-CFTR complex detected by immunoprecipitation. The calumenin-CFTR interaction was also shown by Surface Plasmon Resonance and further confirmed by computational analysis of the predicted calumenin’s partners. Because in our cellular model calumenin was found in the endoplasmic reticulum (ER) by immunofluorescence experiments, we suggest that calumenin is likely involved in the mutated CFTR’s maturation. In conclusion, we showed for the first time that calumenin binds to CFTR and that it is increased in the G551D-CFTR complex. We suggest that it may be involved in the physiopathology of G551D-CFTR and that G551D-CFTR may follow a specific maturation and trafficking pathway. We also hypothesize that UPR may be triggered independently of the retention of G551D-CFTR in the ER because Grp78/Bip expression is increased in the cells. Finally, we propose here that Calumenin is a new CFTR chaperone.

BackgroundMitochondrial genome (mt-genome) data can potentially return artefactual relationships in the higher-level phylogenetic inference of insects due to the biases of accelerated substitution rates and compositional heterogeneity. Previous studies based on mt-genome data alone showed a paraphyly of Cimicomorpha (Insecta, Hemiptera) due to the positions of the families Tingidae and Reduviidae rather than the monophyly that was supported based on morphological characters, morphological and molecular combined data and large scale molecular datasets. Various strategies have been proposed to ameliorate the effects of potential mt-genome biases, including dense taxon sampling, removal of third codon positions or purine-pyrimidine coding and the use of site-heterogeneous models. In this study, we sequenced the mt-genomes of five additional Tingidae species and discussed the compositional and mutational rate heterogeneity in mt-genomes and its effect on the phylogenetic inferences of Cimicomorpha by implementing the bias-reduction strategies mentioned above.ResultsHeterogeneity in nucleotide composition and mutational biases were found in mt protein-coding genes, and the third codon exhibited high levels of saturation. Dense taxon sampling of Tingidae and Reduviidae and the other common strategies mentioned above were insufficient to recover the monophyly of the well-established group Cimicomorpha. When the sites with weak phylogenetic signals in the dataset were removed, the remaining dataset of mt-genomes can support the monophyly of Cimicomorpha; this support demonstrates that mt-genomes possess strong phylogenetic signals for the inference of higher-level phylogeny of this group. Comparison of the ratio of the removal of amino acids for each PCG showed that ATP8 has the highest ratio while CO1 has the lowest. This pattern is largely congruent with the evolutionary rate of 13 PCGs that ATP8 represents the highest evolutionary rate, whereas CO1 appears to be the lowest. Notably, the value of Ka/Ks ratios of all PCGs is less than 1, indicating that these genes are likely evolving under purifying selection.ConclusionsOur results demonstrate that mt-genomes have sites with strong phylogenetic signals for the inference of higher-level phylogeny of Cimicomorpha. Consequently, bioinformatic approaches to removing sites with weak phylogenetic signals in mt-genome without relying on an a priori tree topology would greatly improve this field.Electronic supplementary materialThe online version of this article (10.1186/s12864-018-4650-9) contains supplementary material, which is available to authorized users.

Heterozygous germline mutations in PHOX2B, a transcriptional regulator of sympathetic neuronal differentiation, predispose to diseases of the sympathetic nervous system, including neuroblastoma and congenital central hypoventilation syndrome (CCHS). Whereas the PHOX2B variants in CCHS largely involve expansions of the second polyalanine repeat within the C-terminus of the protein, those associated with neuroblastic tumors are nearly always frameshift and truncation mutations. To test the hypothesis that the neuroblastoma-associated variants exert their effects through loss or gain of protein-protein interactions, we performed a large-scale yeast two-hybrid screen using both wild-type (WT) and six different mutant PHOX2B proteins against over 10,000 human genes. The neuronal calcium sensor protein HPCAL1 (VILIP-3) exhibited strong binding to WT PHOX2B and a CCHS-associated polyalanine expansion mutant, but only weakly or not at all to neuroblastoma-associated frameshift and truncation variants. We demonstrate that both WT PHOX2B, the neuroblastoma-associated R100L missense and the CCHS-associated alanine expansion variants induce nuclear translocation of HPCAL1 in a Ca2+-independent manner, while the neuroblastoma-associated 676delG frameshift and K155X truncation mutants impair subcellular localization of HPCAL1, causing it to remain in the cytoplasm. HPCAL1 did not appreciably influence the ability of WT PHOX2B to transactivate the DBH promoter, nor did it alter the decreased transactivation potential of PHOX2B variants in 293T cells. Abrogation of the PHOX2B-HPCAL1 interaction by shRNA knockdown of HPCAL1 in neuroblastoma cells expressing PHOX2B led to impaired neurite outgrowth with transcriptional profiles indicative of inhibited sympathetic neuronal differentiation. Our results suggest that certain PHOX2B variants associated with neuroblastoma pathogenesis, because of their inability to bind to key interacting proteins such as HPCAL1, may predispose to this malignancy by impeding the differentiation of immature sympathetic neurons.

BackgroundMost studies on the paper mulberry are mainly focused on the medicated and pharmacology, fiber quality, leaves feed development, little is known about its mechanism of adaptability to abiotic stress. Physiological measurement, transcriptomics and proteomic analysis were employed to understand its response to cold stress in this study.MethodsThe second to fourth fully expanded leaves from up to down were harvested at different stress time points forthe transmission electron microscope (TEM) observation. Physiological characteristics measurement included the relative electrolyte leakage (REL), SOD activity assay, soluble sugar content, and Chlorophyll fluorescence parameter measurement. For screening of differentially expressed genes, the expression level of every transcript in each sample was calculated by quantifying the number of Illumina reads. To identify the differentially expressed protein, leaves of plants under 0, 6, 12, 24, 48 and 72 h cold stress wereharvested for proteomic analysis. Finally, real time PCR was used to verify the DEG results of the RNA-seq and the proteomics data.ResultsResults showed that at the beginning of cold stress, respiratory metabolism was decreased and the transportation and hydrolysis of photosynthetic products was inhibited, leading to an accumulation of starch in the chloroplasts. Total of 5800 unigenes and 38 proteins were affected, including the repressed expression of photosynthesis and the enhanced expression in signal transduction, stress defense pathway as well as secondary metabolism. Although the transcriptional level of a large number of genes has been restored after 12 h, sustained cold stress brought more serious injury to the leaf cells, including the sharp rise of the relative electrolyte leakage, the declined Fv/Fm value, swelled chloroplast and the disintegrated membrane system.ConclusionThe starch accumulation and the photoinhibition might be the main adaptive mechanism of the paper mulberry responded to cold stress. Most of important, enhancing the transport and hydrolysis of photosynthetic products could be the potential targets for improving the cold tolerance of the paper mulberry.Electronic supplementary materialThe online version of this article (doi:10.1186/s12864-015-2047-6) contains supplementary material, which is available to authorized users.

In cystic fibrosis (CF), the most frequent mutant variant of the cystic fibrosis transmembrane conductance regulator (CFTR), F508del-CFTR protein, is misfolded and retained in the endoplasmic reticulum (ER) We previously showed that the unfolded protein response (UPR) may be triggered in CF. Since prolonged UPR activation leads to apoptosis via the calcium-calpain-caspase-12-caspase-3 cascade and because apoptosis is altered in CF, our aim was to compare the ER stress-induced apoptosis pathway between wild type (Wt) and F508del-CFTR expressing cells. Here we show that the calcium-calpain-caspase-12-caspase-3 cascade is altered in F508del-CFTR expressing cells. We propose that this alteration is involved in the altered apoptosis triggering observed in CF.