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Ultraviolet A (UVA) radiation is capable of inducing various types of physiological effects related to all macromolecules in insects. However, the molecular mechanisms of insect responses to UVA radiation are still poorly understood. Transcriptional regulation of the expression of UVA-responsive genes is a crucial part of insect responses to UVA radiation. This research used the model insect Drosophila melanogaster to test its transcriptional response to UVA radiation via RNA sequencing, and systematically analyzed the head gene-expression profiles between different time points (0, 0.5, and 1.0 h). In all, 1,678 differentially-expressed (DE) genes were detected via pairwise comparisons among three different RNA-Seq libraries. Most DE genes, down-regulated continually or at the end point, were classified into cluster (1) of significant model profiles. Furthermore, combined with KEGG/pathways and Gene ontology enrichment analysis, DE genes greatly related to stress and defense responses, metabolic process, and enriched in signaling pathways responding to UVA radiation. A subset of differentially-expressed genes were selected to verify the RNA-Seq results through quantitative real-time PCR; the results of quantitative real-time PCR analyses strongly correlated with the RNA-Seq data. The results provided the extensive genetic components and possible mechanisms for insect resistance/adaptation to UVA radiation.

Ultraviolet A (UVA) radiation (400–315 nm) is the major component of solar ultraviolet (UV) radiation that reaches the Earth's surface due to the role of the stratospheric ozone. UVA radiation can induce various types of negative effects in all organisms including insects, such as oxidative stress, cell death, and photo-receptor damage. The objective of this study was to further elucidate the biological effects of UVA radiation on diurnal insects. In the present study, the effects of UVA radiation on adult longevity and fecundity in a model diurnal insect, Drosophila melanogaster Meigen, 1830 (Diptera: Drosophilidae), irradiated at different UVA-exposure times and intensities were investigated, as well as the developmental duration and cumulative survival rate of the first filial generation. The longevity of adults exposed to relatively low-intensity UVA radiation was prolonged for both sexes, and there was a significant increase observed after exposure for 3 h/day. The results also showed that ...

Streptococcus agalactiae is an important pathogen in humans, cows, fish and so on, which causes pneumo-nia, sepsis, meningitis and sometimes death in human and mastitis in cows. In fish, S. agalactiae can result in massive kills of fish and is responsible for heavy eco-nomic losses in many species of freshwater, marine, and estuarine fish worldwide. Many reports showed that the infections characterized by septicemia and men-ingoencephalitis (Evans et al., 2002, 2006; Mian et al., 2009; Geng et al., 2012; Delannoy et al., 2013). Now, many antimicrobials have routinely been the drugs for prophylactic strategies and treatment of the infections of S. agalactiae. But, more and more multidrug resistant strains represent a critical challenge for antimicrobial therapy.Quorum sensing (QS) is a cell-cell communication mechanism to coordinate social activities. It is well known that one QS signal called autoinducer-2 (AI-2) is shared by both Gram-positive and Gram-negative bacte-ria (Bassler, 1999; Miller and Bassler, 2001; Waters and Bassler, 2005; Federle, 2009; Zhao et al., 2010; Wang et al., 2011). AI-2 molecule is formed as a result of spontaneous rearrangement of dihydroxy-2,3-pentanedi-one (DPD), which is catalyzed by the conserved and widespread luxS enzyme (Chen et al., 2002; Xavier and Bassler, 2003). Many studies have highlighted the sig-nificance of luxS/AI-2 in the biological processes of vari-ous bacterial species including antimicrobial production, biofilm formation, carbohydrate metabolism and viru-lence expression and so on (Bassler et al., 1993; Vendeville et al., 2005; Doherty et al., 2006; Ahmed et al., 2007, 2009; Choi et al., 2007; Palaniyandi et al., 2013).Interestingly, S. agalactiae also possesses a func-tional luxS gene and has the ability to produce AI-2 molecule. Analysis of 3D structure showed that deduced LuxS protein contained conserved active cen-ter (His-57, His-61, Cys-127) and Zn

The developmental competence of porcine parthenotes cultured in porcine zygote medium-3 (PZM-3) and North Carolina State University-23 (NCSU-23) media was investigated. After in vitro maturation oocytes were electro-activated, and the subsequent developmental competence, rates of apoptotic, fragmented and arrested embryos from the two media were evaluated. Also, the ratio of mRNA expression of Bcl-2 and Bax gene was determined. Results demonstrated that cleavage, blastocyst, hatched blastocyst rates, and blastocyst cell numbers were significantly higher in PZM-3 than in NCSU-23. The rate of fragmented embryos in PZM-3 was lower than in NCSU-23 on d 1 and 3 ( P P P P P P

Streptococcus agalactiae is an important human and animal pathogen. To better understand the genetic features and evolution of S. agalactiae, multiple factors influencing synonymous codon usage patterns in S. agalactiae were analyzed in this study. A- and U-ending rich codons were used in S. agalactiae function genes through the overall codon usage analysis, indicating that Adenine (A)/Thymine (T) compositional constraints might contribute an important role to the synonymous codon usage pattern. The GC3% against the effective number of codon (ENC) value suggested that translational selection was the important factor for codon bias in the microorganism. Principal component analysis (PCA) showed that (i) mutational pressure was the most important factor in shaping codon usage of all open reading frames (ORFs) in the S. agalactiae genome; (ii) strand specific mutational bias was not capable of influencing the codon usage bias in the leading and lagging strands; and (iii) gene length was not the important factor in synonymous codon usage pattern in this organism. Additionally, the high correlation between tRNA adaptation index (tAI) value and codon adaptation index (CAI), frequency of optimal codons (Fop) value, reinforced the role of natural selection for efficient translation in S. agalactiae. Comparison of synonymous codon usage pattern between S. agalactiae and susceptible hosts (human and tilapia) showed that synonymous codon usage of S. agalactiae was independent of the synonymous codon usage of susceptible hosts. The study of codon usage in S. agalactiae may provide evidence about the molecular evolution of the bacterium and a greater understanding of evolutionary relationships between S. agalactiae and its hosts.

Progesterone is an important steroid hormone in the regulation of the bovine estrous cycle. The steroidogenic acute regulatory protein (StAR) is an indispensable component for transporting cholesterol to the inner mitochondrial membrane, which is one of the rate-limiting steps for progesterone synthesis. Low-density lipoprotein (LDL) supplies cholesterol precursors for progesterone formation, and the lysosomal degradation pathway of LDL is essential for progesterone biosynthesis in granulosa cells after ovulation. However, it is currently unknown how LDL and lysosomes coordinate the expression of the StAR gene and progesterone production in bovine granulosa cells. Here, we investigated the role of lysosomes in LDL-treated bovine granulosa cells. Our results reported that LDL induced expression of StAR messenger RNA and protein as well as expression of cholesterol side-chain cleavage cytochrome P-450 (CYP11A1) messenger RNA and progesterone production in cultured bovine granulosa cells. The number of lysosomes in the granulosa cells was also significantly increased by LDL; whereas the lysosomal inhibitor, chloroquine, strikingly abolished these LDL-induced effects. Our results indicate that LDL promotes StAR expression, synthesis of progesterone, and formation of lysosomes in bovine granulosa cells, and lysosomes participate in the process by releasing free cholesterol from hydrolyzed LDL.

Oocyte aging due to delayed fertilization is associated with declining quality and developmental potential. Intracellular calcium (Ca(2+)) concentration ([Ca(2+)]i) regulates oocyte growth, maturation, and fertilization and has also been implicated in aging. Using bovine oocytes, we tested the hypothesis that oocyte aging could be delayed by reducing [Ca(2+)]ivia blocking the influx of extracellular Ca(2+) or chelating ooplasmic free Ca(2+). After IVM, cumulus-oocyte complexes or denuded oocytes were cultured in medium supplemented with 1-octanol, phorbol 12-myristate 13-acetate, or 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid tetrakis-acetoxymethyl ester (BAPTA-AM) to manipulate [Ca(2+)]i. Addition of 1-mM 1-octanol increased blastocyst development rates in the cumulus-oocyte complexes aged for 6 hours by IVF and for 6, 12, and 24 hours by parthenoactivation, and this effect was independent of the presence of cumulus cells. The intracellular levels of ATP, Glutathione, and Glutathione disulfide were not affected by 1-octanol, but [Ca(2+)]i was significantly decreased. When oocytes were cultured in Ca(2+)-free medium for 12 hours, the blastocyst development rate was greater and the beneficial effects of 1-octanol on oocyte aging were abolished. However, when the medium was supplemented with phorbol 12-myristate 13-acetate, [Ca(2+)]i increased and the blastocyst development rate decreased. Moreover, BAPTA-AM reduced [Ca(2+)]i and increased blastocyst development rates after IVF or parthenoactivation. We conclude that the age-associated developmental potency decline was delayed by blocking the influx of extracellular Ca(2+) or reducing ooplasmic free Ca(2+). 1-Octanol, BAPTA-AM, or Ca(2+)-free medium could be used to lengthen the fertilization windows of aged bovine oocytes.

Imidazole, an organic alkaloid, is an important pharmacophore in drug discovery. Anti-neoplastic potential of imidazole derivatives has been documented in several studies; however, mechanisms by which tumor cells respond to these stimuli remain to be elucidated. Autophagy and apoptosis have key roles in tumorigenesis and tumor treatment. In this study, we systematically examined autophagic events induced by imidazole in HEC-1B cells. Accumulation of autophagic vacuoles in imidazole-treated cells was verified by conversion of LC3 protein, as well as confocal and transmission electron microscopy. Furthermore, imidazole blocked autophagic degradation by impairing maturation of autophagosomes into autolysosomes. Concurrently, imidazole treatment induced apoptosis in HEC-1B cells, accompanied by activation of caspase 9 and 3. The proapoptotic effect was mediated by increased Bim expression. Moreover, imidazole upregulated the protein level of Foxo3a and induced its increased nuclear localisation. In addition, siRNA-mediated silencing of FoxO3a effectively attenuated imidazole-induced Bim upregulation and cell death, indicating direct involvement of this pathway in the imidazole-induced apoptosis. Taken together, our data provided a molecular link between imidazoles and anticancer therapies; understanding of these properties of imidazole is essential for development of effective cancer therapeutics using imidazoles.

Lysosomotropic amines cause serious side effects such as cytoplasmic vacuolation and cell death. TRPML1 (also known as mucolipin1), a member of the transient receptor potential (TRP) protein family, may regulate fusion/fission of vesicles along the endocytic pathway and some aspects of lysosomal ion homeostasis. Nevertheless, it is still unknown whether TRPML1 is involved in death of mammalian cells induced by lysosomotropic agents. In this study, imidazole was used as a model to investigate the role of TRPML1 in the cytotoxicity of lysosomotropic agents. Overexpression of wild-type TRPML1 inhibited imidazole-induced vacuole formation and cell death in human endometrial adenocarcinoma (HEC-1B) cells. In contrast, siRNA-mediated TRPML1 knockdown increased the cell death induced by imidazole. Bafilomycin A1 raises the pH of acidic organelles and therefore suppresses accumulation of weak bases in them. Similarly, lysosomal pH was raised in TRPML1-overexpressing cells; therefore, we inferred that TRPML1 protected against imidazole toxicity by regulating the pH of acidic organelles. We concluded that TRPML1 had a novel role in protecting against lysosomotropic amine toxicity.

Ultrafiltration (UF) membranes of six selected poly(amidesulfonamide)s (PASAs) were prepared and studied. The pure water flux and the retention of albumin (bovine serum) were used to evaluate the quality of the UF performance of the fabricated membrane. Membranes with good mechanical strength were obtained by using the phase inversion method. A comparison of the UF performance of the PASA membranes fabricated from a casting solution containing 12% w/w PASAs and 4% w/w lithium bromide in dimethylacetamide was made. The best retention of albumin ( bovine serum) by membranes prepared under the conditions studied from the selected homopolymers of PASAs, and their corresponding pure water flux at 0.207 MPa, ranged from 84.6 to 100% and 120 to 396 L m -2 h -1 , respectively.

International audience; UltravioletA (UVA) radiation, the major component of solar ultraviolet (UV) radiation reaching the earthOs surface, leads to negative effects in insects, such as oxidative stress, photoreceptor damage, and cell death. To better understand the molecular mechanisms of insect response to UVA radiation, suppression subtractive hybridization (SSH) and real-time quantitative polymerase chain reaction approaches were combined to reveal differential transcript expression in Drosophila melanogaster Meigen, 1830 (Diptera: Drosophilidae). In this study, two subtractive cDNA libraries were constructed and sequenced, obtaining 131 high-quality unique expressed sequence tags (ESTs) that were up-or downregulated in D. melanogaster exposed to UVA radiation for 0.5 h. Of the 131 ESTs, 102 unique ESTs were differentially expressed and classified into 10 functional categories. The results showed that UVA radiation induces expression of genes related to stress and defense response and metabolism. Potential transcription factor binding motifs upstream of these genes are associated with multiple signaling pathways that may help the insect cope with the stress of UVA radiation. To our knowledge, this is the first analysis of insect response toUVAradiation at the transcriptional level. Our results reveal that UVA radiation influences the expression profiles of stress-responsive genes and provide further insights into the mechanisms of adaptive response to UVA radiation stress.

Accumulating evidence indicates that cellular and molecular abnormalities occur during oocyte aging, including fragmentation, increases in intracellular reactive oxygen species (ROS), and abnormal Ca(2+) oscillations. The objective of the present study was to characterize the relationships between intracellular ROS, Ca(2+) homeostasis of endoplasmic reticulum (ER), and fragmentation in aged porcine MII oocytes. Prolonged culture (36 h) of porcine oocytes resulted in elevated intracellular ROS level, impaired ER Ca(2+) homeostasis (i.e., Ca(2+) storage, Ca(2+) rising patterns after electroactivation, and the cluster distribution of ER), and increased fragmentation rates. However, when the porcine oocytes were treated with 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid tetrakis(acetoxymethyl ester), an intracellular Ca(2+) chelator, the fragmentation was significantly inhibited during in vitro aging. In order to pursue the underlying mechanisms, H2O2 and cycloheximide (CHX) were used to artificially increase or inhibit, respectively, the intracellular ROS levels in aged porcine oocytes during in vitro culture. The results demonstrated that incubation of porcine MII oocytes with H2O2 damaged the ER clusters and the Ca(2+) regulation of ER, leading to a high proportion of fragmented oocytes. In contrast, CHX, an intracellular inhibitor of ROS generation, prevented both increase of ROS level and damage of the ER Ca(2+) homeostasis in porcine oocytes during aging, resulting in low fragmentation rate. We conclude that the increased intracellular ROS damaged the ER clusters and ER Ca(2+) homeostasis, resulting in a disorder in ooplasmic free Ca(2+), which caused the fragmentations seen in porcine MII oocytes during aging.