Line S2 Research Articles

ECOLOGICAL PLASTICITY AND STABILITY OF WINTER WHEAT VARIETIES IN THE CONDITIONS OF THE SOUTHERN STEPPE OF UKRAINE (PART 1 – YEARS WITH SUFFICIENT MOISTURE)

The purpose of our research was to study and analyze the environmental stability and adaptability to different environments of winter wheat varieties selected by the Institute of Climate-oriented Agriculture of the National Academy of Sciences and the Selection and Genetic Institute of the National Center for Seed Science and Varietal Research of the National Academy of Sciences in the conditions of the Southern Steppe of Ukraine. Research materials and methods. The reaction of 18 varieties of winter wheat to different growing conditions was studied at the Askania State Agricultural Research Station in the village of Tavrychanka, Kherson region (46°33’12”N; 33°49’13”E; 39 m above sea level) during 2015/16–2019/20. Research was conducted under different conditions of irrigation: with irrigation and without irrigation. Analysis of environmental stability and adaptability to different environments of winter wheat varieties was carried out using various parameters. Research results and their discussion. The obtained experimental data made it possible to single out the varieties of winter wheat with the highest productivity in terms of maximum productivity – Burhunka – 8.46 t/ha, Tradytsiia odes’ka – 8.32 and Schedrist’ odes’ka – 8.58 t/ ha, in terms of minimum productivity – Koshova – 7.14 t/ha, Khersons’ka bezosta – 7.00, Lira odes’ka – 7.24 t/ha and Tradytsiia odes’ka – 7.05 t/ha. According to the parameters of adaptability, the Harantiia odes’ka variety was selected as the most stable, while the Schedrist’ odes’ka was selected as an intensive type variety. According to the correlation analysis, the parameters of adaptability were selected: the level of resistance to stressful conditions (RS), the regression coefficient (bi), the variance of the deviation from the regression line (s2 di), the sign of the stability of the genotype reaction (σ2 SACi), the compensation coefficient (Kgi), the relative stability of the genotype (sgi) , the selection value of the genotype (SVGi), the selection value of the variety (Sc) by which the type of variety can be most clearly characterized. Conclusions. According to them and the biplot analysis, the isolated parameters of adaptability were selected as the most stable varieties Koshova, Khersons’ka bezosta, Harantiia odes’ka and Lira odes’ka, instead Schedrist’ odes’ka and Burhunka were selected as intensive type varieties.

PSIII-10 The Effect of Sire Line on Grow-finish Performance, Carcass Characteristics, and Meat Pricing Variables for Commercial Crossbred Pigs

Abstract The objective of this study was to evaluate the effect of sire line on wean-to-finish performance, carcass characteristics, and meat pricing variables. Pigs used for this study were the progeny of a commercial Landrace x Large White female mated to one of the following sire lines: a purebred Duroc line (Line S1), or a synthetic (Line S2) or purebred Duroc line (Line S3) originating from a different genetic source. An equivalent number of pigs (n =144) were used per group, for 432 pigs placed on test. Average initial weights per line were 6.67 ± 0.24, 6.67 ± 0.24, and 6.60 ± 0.24 for lines S1, S2, and S3, respectively. At placement, 8 pigs were assigned to each pen (split sex) and blocked by line and initial BW, with 18 replicates per line. Data were analyzed at the pen level using the PROC MIXED procedure of SAS, where the effects of line, sex, and line*sex were fitted as fixed effects and replicate was fitted as a random effect. Overall, piglets from line S2 (0.403 vs 0.381; P ≤ 0.0004) and line S3 (0.402 vs 0.381; P ≤ 0.001) had improved GF compared with piglets from line S1. The ADFI was greater in piglets from line S1 relative to piglets from line S2 (2.264 vs 2.117 kg; P ≤ 0.0001) and line S3 (2.264 vs 2.159 kg; P ≤ 0.004). The ADG, HCW, dressing yield, and loin depth were not different among treatment (P > 1.00). Piglets from line S3 had greater percent lean (57.12 vs 56.29 %; P ≤ 0.0001) and better carcass grade premium ($7.07 vs 6.60; P ≤ 0.0291) relative to piglets from line S1. In conclusion, line S1 piglets had greatest ADFI, but line S2 pigs and line S3 piglets had better feed efficiency. Line S3 pigs were leaner and had better carcass grade premium.

PSIII-9 The Effect of Sire Line on Reproductive Performance During Lactation

Abstract The objective of this study was to estimate the effect of sire line on sow and piglet performance during lactation. Commercial Landrace x Large White females (n = 60) were bred to one of the following sire lines: a purebred Duroc line (Line S1), a synthetic (Line S2), or purebred Duroc (Line S3) from a different genetic source. Matings were balanced by line and parity. Females were fed a common gestation and lactation diet during these respective phases. Sow and piglet data were analyzed as a completely randomized design using the GLM procedure of SAS. Results show that, during lactation, females bred to line S3 lost significantly (P = 0.01) more BW (-16.93 ± 3.56 kg) than females bred to line S2 (-2.00 ± 3.50 kg). However, no evidence of a difference (P = 0.18) in BW loss was detected between females bred to line S3 (-16.93 ± 3.56 kg) vs. Line S1 (-7.90 ± 3.56 kg). Further, sows bred to line S3 weaned significantly (P = 0.03) more piglets (12.0 ± 0.28) than females bred to line S2 (10.9 ± 0.27), but not (P = 0.1) compared to females bred to line S1 (11.7 ± 0.27). No significant effect of line (P > 0.05) or parity (P > 0.05) on total number of piglet’s born, number born alive, number of stillborn piglets, or preweaning mortality was detected. The number of mummified fetus tended to be lower in line S2 (0.17 vs 0.66; P = 0.079) and line S3 (0.12 vs 0.66; P = 0.051) sows compared with line S1 sows, respectively. In conclusion, sire line did not have a significant effect on total number born, number born alive, number stillborn, or preweaning mortality. However, females bred to line S3 lost significantly more BW during lact but weaned significantly more piglets than females bred to line S2.

Compared activity of agonist molecules towards ecdysone receptor in insect cell-based screening system

ABSTRACT: The ecdysone receptor, naturally activated by steroidal hormones, is a key protein for molting and reproduction processes of insects. Artificial activation of such receptor by specific pesticides induces an anomalous process of ecdysis, causing death of insects by desiccation and starvation. In this paper, we established a protocol for screening agonistic molecules towards ecdysone receptor of insect cells line S2 (Diptera) and Sf9 (Lepidoptera), transfected with the reporter plasmid ere.b.act.luc. Therefore, we set dose-response curves with the ecdysteroid 20-hydroxyecdysone, the phytoecdysteroid ponasterone-A, and tebufenozide, a pesticide belonging to the class of diacylhydrazines. In both cell lines, the median effective concentration values on reporter gene induction (EC50) of ponasterone-A was the smallest, meaning the most active agonist molecule. In Sf9 cells, tebufenozide had as smaller EC50 than 20-hydroxyecdysone, indicating the high agonistic capability and lepidopteran specificity. The protocol established in this study can be useful for a quick screening and rational research of site-specific pesticides.

Expression of foreign proteins by antimicrobial peptide gene promoters in mosquitoes

Background: The mosquito Aedes aegypti is a major vector for transmission of viruses causing dengue fever, yellow fever, Zika, and chikungunya infection. Functional analysis of mosquito genes and individual viral genes can be a powerful approach to study vector–virus interactions but is often hampered by a lack of suitable promoters to drive exogenous viral gene expression in mosquito cells in vitro and in vivo. Object: To search for potential promoter candidates that can be used to express foreign genes and particularly viral proteins in a mosquito model system. Materials and Methods: we characterized the ability of the promoters of three Ae. aegypti antimicrobial peptide (AMP) genes to drive the expression of marker proteins (luciferase, GFP, the NS3 protein of two flaviviruses, and rabies virus glycoprotein) in mosquito cells and adult female mosquitoes, and in other insect cells as well. Results: The promoters of the defensin A4 and cecropin B1 genes produced robust expression of luciferase and GFP in the Ae. aegypti cell line CCL125, Aedes albopictus cell line C6/36, Drosophila melanogaster cell line S2, and Spodoptera frugiperda cell line Sf21. These AMP gene promoters also had the ability to drive NS3 and GFP expression in adult tissues of Ae. aegypti, Ae. albopictus, and Culex tritaeniorhynchus in vivo, which may suggest evolutionary conservation of AMP gene promoter activity across mosquito lineages. Conclusions: These promoters could provide a valuable tool for ectopically expressing viral genes and studying their interactions with the mosquito vectors.

Performance of Understanding Students’ Construction In The Naming Fraction of The Three Representation

The purpose of this study is to describe students’ thinking processes in constructing the names of the fraction in circular, rectangular and number line representations by using APOS Theory (Action, Process, Object, and Scheme). For that purpose, the researcher used qualitative research approach. The subject of this research is the students of class XI in Malang. The process of collecting data begins with giving the questions to the subject to be completed. Then the students are interviewed to reinforce the answers that have given. From the performance of the subject and results of the interview, the data are analyzed using indicators of APOS Theory is action, process, object, and scheme. The results of this study indicate that for the thinking process students with circle representation S1 reached the stage of the scheme, while for S2 and S3 only reached the stage of the process. With the rectangular representation, S1 and S2 reach the stage of the scheme, but different with S3, S3 that reached the stage of the process. Moreover, the thinking process by using the number line representation S1, S2 and S3 can reach the stage of the scheme. To construct the name of the fraction with a circle and rectangular representation the subject is using the whole-part concept and area model of the fraction. As for the representation that uses the number line the subject using the concept of measurement and associates it with the length model in constructing the name of the fraction.

An N-terminal di-proline motif is essential for fatty acid–dependent degradation of Δ9-desaturase in Drosophila

The Δ9-fatty acid desaturase introduces a double bond at the Δ9 position of the acyl moiety of acyl-CoA and regulates the cellular levels of unsaturated fatty acids. However, it is unclear how Δ9-desaturase expression is regulated in response to changes in the levels of fatty acid desaturation. In this study, we found that the degradation of DESAT1, the sole Δ9-desaturase in the Drosophila cell line S2, was significantly enhanced when the amounts of unsaturated acyl chains of membrane phospholipids were increased by supplementation with unsaturated fatty acids, such as oleic and linoleic acids. In contrast, inhibition of DESAT1 activity remarkably suppressed its degradation. Of note, removal of the DESAT1 N-terminal domain abolished the responsiveness of DESAT1 degradation to the level of fatty acid unsaturation. Further truncation and amino acid replacement analyses revealed that two sequential prolines, the second and third residues of DESAT1, were responsible for the unsaturated fatty acid-dependent degradation. Although degradation of mouse stearoyl-CoA desaturase 1 (SCD1) was unaffected by changes in fatty acid unsaturation, introduction of the N-terminal sequential proline residues into SCD1 conferred responsiveness to unsaturated fatty acid-dependent degradation. Furthermore, we also found that the Ca2+-dependent cysteine protease calpain is involved in the sequential proline-dependent degradation of DESAT1. In light of these findings, we designated the sequential prolines at the second and third positions of DESAT1 as a "di-proline motif," which plays a crucial role in the regulation of Δ9-desaturase expression in response to changes in the level of cellular unsaturated fatty acids.

The suitability of some blood gas and biochemical parameters as diagnostic tools or early indicators of ascites syndrome in broiler sire lines.

In recent few years, there have been some attempts to find a reliable indicator trait as a selection criterion against susceptibility to ascites syndrome (AS). Blood parameters were of great interest as they could be measured in live animals without implementing an ascites-inducing challenge (AIC). In this work, the suitability of some blood parameters was evaluated for diagnosing AS-susceptible chicks in later steps of the disease in trial 1 as well as their early predictive ability in trial 2. In the first trial, one hundred 1-day-old chicks from two pure broiler lines namely S1 and S2 and, in the second trial, 226 1-day-old chicks from line S2 were subjected to AIC. Saline drinking water (1200mg/l) and lower-than-standard ambient temperatures were the implemented AICs in trials 1 and 2 respectively. The blood parameters including pH, partial pressure of O2 (pO2 ), partial pressure of CO2 (pCO2 ), bicarbonate ion concentration (BIC), percentage of haematocrit (HCT) and saturated haemoglobin (SaO2 ) were measured twice per each bird at days 28 and 35 in trial 1 and once in trial 2 at day 21. The results of the first trial revealed that in line S2 some of the blood parameters differed significantly between the ascitic and non-ascitic groups following exposure to AIC. In this line, the incidence of AS was accompanied by a lower pO2 , SaO2 and BIC, while with higher pCO2 and HCT values. In the second trial, however, although almost all of the parameters showed meaningful differences between the ascitic and non-ascitic broilers, only mean difference of BIC parameter was statistically significant. The general conclusion of this study is that the blood parameters can somewhat have diagnostic ability in the condition in which the AIC is already present, whereas the results did not approve their usefulness as early predictors of AS.

Abstract 4503: A small molecule glycomimetic antagonist of E-selectin (GMI-1271) prevents pancreatic tumor metastasis and offers a novel treatment for improved efficacy of chemotherapy

Abstract The processes of intra- and extravasation of tumor cells into and out of the blood and lymphatic systems are crucial steps during metastasis to distant organ sites. These processes are tightly regulated by the initial binding of sialyl Lewis A and sialyl Lewis X (sialyl Le A/X) carbohydrate moeities found on tumor cells to the adhesion protein E-selectin expressed on the activated endothelium. GMI-1271 is a small molecule glycomimetic rationally designed based on the bioactive conformation of sialyl Lea/x and is a potent and specific antagonist of E-selectin. In vitro treatment of human lymphatic endothelial cells with GMI-1271 resulted in a decrease in the number of sialyl Lewis A-expressing pancreatic cancer cells (S2.013 and BxPC-3) binding to the endothelium in a dose-dependent manner. GMI-1271 treatment also inhibited the transendothelial migration of S2.013 and BxPC-3 cells through a lymphatic cell monolayer. We evaluated the in vivo efficacy of GMI-1271 following orthotopic implantation of pancreatic tumor cell line S2.013, which expresses high levels of sialyl Lewis A (CA19-9), into nude mice. Following 2 weeks of tumor growth, mice were treated by intraperitoneal injections for 4 weeks with either PBS once daily, once daily with 40mg/kg GMI-1271 (low dose), twice daily with 40mg/kg GMI-1271 (high dose), twice a week with 60mg/kg gemcitabine injections, combination low dose GMI-1271 and gemcitabine injections, or combination high dose GMI-1271 and gemcitabine injections. Co-treatment of either low or high dose GMI-1271 with gemcitabine resulted in a significant decrease in the number of metastasis to the lymph nodes (p=0.02 low dose; p=0.04 high dose). In addition, compared with gemcitabine alone, low dose GMI-1271 plus gemcitabine was found to be effective at reducing the number of metastatic lesions (per histological section) in the liver (p=0.001), lung (p=0.026) and diaphragm (p=0.01). Based on the significant effects of combination therapy on tumor metastasis, the small molecule glycomimetic antagonist to E-selectin, GMI-1271, offers great promise in preventing pancreatic tumor cell entry into the blood and lymphatic systems and offers a novel treatment for the improved efficacy of standard chemotherapy. Citation Format: Maria M. Steele, Prakash Radhakrishnan, John L. Magnani, Michael A. Hollingsworth. A small molecule glycomimetic antagonist of E-selectin (GMI-1271) prevents pancreatic tumor metastasis and offers a novel treatment for improved efficacy of chemotherapy. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4503. doi:10.1158/1538-7445.AM2014-4503

Evaluation of abiotic stress tolerance and physiological characteristics of potato (Solanum tuberosum L. cv. Kennebec) that heterologously expresses the rice Osmyb4 gene

MYB transcription factors are involved in diverse biochemical and physiological processes, including hormone signaling, defense, and stress responses. In the present study, we developed a transgenic potato (Solanum tuberosum L. cv. Kennebec) expressing the rice Osmyb4 gene, which encodes the transcription factor MYB4. The transgene was under the control of either the constitutive CaMV35S promoter or the stress-induced Arabidopsis COR15a promoter. The potential involvement of MYB4 in certain physiological processes and the abiotic stress response in the potato was evaluated. The transgenic plants did not exhibit growth retardation, and they showed no significant difference (P < 0.05) in tuber yield from that of non-transgenic wild-type plants. Although the chlorophyll a and b as well as the anthocyanin contents of the six transgenic lines were similar to those of the wild type, the transgenic line S2 presented a significantly higher carotenoid content. The total sugar contents of the lines S2 and M48 were significantly higher than that of the wild-type plants. S2 and M48 were significantly more tolerant of salinity than the wild type, according to measured growth parameters. Transgenic plants grown under a high concentration of boric acid (3 mM) exhibited greater survival rates than non-transgenic control plants. On the other hand, the transgenic plants did not show an improvement in freezing tolerance. Overall, our results indicated that MYB4 may affect diverse processes such as carotenoid biosynthesis, sugar metabolism, and salinity tolerance in potato, and that it may be an upstream regulatory element of these processes.

Cofilin regulator 14-3-3ζ is an evolutionarily conserved protein required for phagocytosis and microbial resistance

Phagocytosis is an ancient cellular process that plays an important role in host defense. In Drosophila melanogaster phagocytic, macrophage-like hemocytes recognize and ingest microbes. We performed an RNAi-based in vitro screen in the Drosophila hemocyte cell line S2 and identified Abi, cpa, cofilin regulator 14-3-3ζ, tlk, CG2765, and CG15609 as mediators of bacterial phagocytosis. Of these identified genes, 14-3-3ζ had an evolutionarily conserved role in phagocytosis: bacterial phagocytosis was compromised when 14-3-3ζ was targeted with RNAi in primary Drosophila hemocytes and when the orthologous genes Ywhab and Ywhaz were silenced in zebrafish and mouse RAW 264.7 cells, respectively. In Drosophila and zebrafish infection models, 14-3-3ζ was required for resistance against Staphylococcus aureus. We conclude that 14-3-3ζ is essential for phagocytosis and microbial resistance in insects and vertebrates.

Control of NK cell activation by distribution and mobility of ligands on target cells (134.16)

Abstract Natural killer (NK) cells are large granular lymphocytes that comprise 5-15% of peripheral blood mononuclear cells and function through cytokine production or cytotoxicity. The response of NK cells to contact with other cells is regulated through many different receptor-ligand interactions. However, it is not clear yet to what extent the distribution and mobility of ligands anchored into the plasma membrane of target cells influence NK cell activation and immune synapse formation during NK-target cell interactions. To study the role of the distribution and mobility of ligands on target cells, and to avoid the use of toxic inhibitors such as cyclodextrin, cholesterol-auxotroph Drosophila cell line S2 was transfected with GPI-linked CD48 (the ligand of NK cell receptor 2B4) and ULBP1 (the ligand of NK cell receptor NKG2D) and grown in serum-free conditions to eliminate cholesterol-enriched domains. 2B4- and NKG2D-dependent activation of NK cells was altered when the ligands where expressed in cholesterol-free S2 cells, suggesting a role of target cell membrane micro-domains in the response of NK cells. Experiments are underway to test how the mobility of ligands on the target cell may influence recognition by NK cells.

Biochemical Characterization of Transporter Associated with Antigen Processing (TAP)-Like (ABCB9) Expressed in Insect Cells

The ATP-binding cassette (ABC) transporter, transporter associated with antigen processing (TAP)-like (TAPL) tagged with a histidine cluster was overexpressed, amounting to as much as 1-2% of total membrane proteins in Drosophila cell line S2. TAPL was effectively solubilized from membranes by Triton X-100, NP-40 and n-dodecyl-beta-D-maltoside. Solubilized TAPL bound ATP-agarose and adenosine 5'-diphosphate (ADP)-agarose but not adenosine 5'-monophosphate (AMP)-agarose. The binding was competed for by excess free ATP, ADP, guanosine 5'-triphosphate (GTP) and dATP but not by AMP. Pyrimidine nucleotides such as uridine 5'-triphosphate (UTP) and cytidine 5'-triphosphate (CTP) were less effective competitors, suggesting that purine nucleotide triphosphates are substrates for TAPL. The ATP-binding of TAPL required Mg(2+), and was observed at neutral pH. Chemical cross-linking experiments suggested that TAPL forms a homodimer in the membrane and under the solubilized conditions.

Expression of particulate-form of Japanese encephalitis virus envelope protein in a stably transfected Drosophila cell line

BackgroundJapanese encephalitis virus (JEV), a member of the family Flaviviridae, is an important mosquito-borne human pathogen. Its envelope glycoprotein (E) is the major determinant of the pathogenicity and host immune responses. In the present study, we explored the feasibility of producing recombinant JEV E protein in the virus-free Drosophila expression system.ResultsThe coding sequence for the signal sequence of premembrane and E protein was cloned into the Drosophila expression vector pAc5.1/V5-His. A Drosophila cell line S2 was cotransfected with this construct as well as a plasmid providing hygromycin B resistance. A cell line expressing the JEV E protein was selected by immunofluoresence, confocal microscopy, and western blot analysis using three different monoclonal antibodies directed against JEV E protein. This cell line was stable in the yield of JEV E protein during two months in vitro maintenance in the presence of hygromycin B. The results showed that the recombinant E protein had an expected molecular weight of about 50 kilodalton, was immunoreactive with all three monoclonal antibodies, and found in both the cytoplasm and culture supernatant. Sucrose gradient ultracentrifugation analysis revealed that the secreted E protein product was in a particulate form. It migrated to the sucrose fraction with a density of 1.13 g/ml. Balb/c mice immunised with the sucrose fraction containing the E protein particles developed specific antibodies. These data show that functioning JEV E protein was expressed in the stable S2 cell line.ConclusionThe Drosophila expression system is a more convenient, cheaper and safer approach to the production of vaccine candidates and diagnostic reagents for JEV.

Transgressive segregation for reduced glucosinolate content in Brassica carinata A. Braun

AbstractSuccessful commercial utilization of the meal by‐product of Brassica oilseed crops requires the cultivation of cultivars with low glucosinolate (GSL) content in the seeds; however, such cultivars are not yet available in Brassica carinata. The objective of the present research was to search for transgressive segregants with further‐reduced GSL content in the progeny of crosses involving four B. carinata lines with reduced GSL content (90 compared with 120 μmol/g seed in standard germplasm). The four lines were crossed following a diallel design and F2 phenotypes (F3 seed bulked) were analysed for GSL content. F2 phenotypes with a transgressive GSL content lower than the parents were identified in all crosses involving the line S2–1241, suggesting that this line carries alleles for reduced GSL content not present in the other lines. F3 : 4 lines from transgressive F2 phenotypes were evaluated for 2 years, which resulted in the selection of an F3 : 4 line with an average GSL content of 58 and 46 μmol/g seed, respectively compared with 84 and 62 μmol/g seed, respectively in S2–1241.

High Affinity Transport of Taurine by the Drosophila Aspartate Transporter dEAAT2

Excitatory amino acid transporters (EAATs) are structurally related plasma membrane proteins known to mediate the Na(+)/K(+)-dependent uptake of the amino acids l-glutamate and dl-aspartate. In the nervous system, these proteins contribute to the clearance of glutamate from the synaptic cleft and maintain excitatory amino acid concentrations below excitotoxic levels. Two homologues exist in Drosophila melanogaster, dEAAT1 and dEAAT2, which are specifically expressed in the nervous tissue. We previously reported that dEAAT2 shows unique substrate discrimination as it mediates high affinity transport of aspartate but not glutamate. We now show that dEAAT2 can also transport the amino acid taurine with high affinity, a property that is not shared by two other transporters of the same family, Drosophila dEAAT1 and human hEAAT2. Taurine transport by dEAAT2 was efficiently blocked by an EAAT antagonist but not by inhibitors of the structurally unrelated mammalian taurine transporters. Taurine and aspartate are transported with similar K(m) and relative efficacy and behave as mutually competitive inhibitors. dEAAT2 can mediate either net uptake or the heteroexchange of its two substrates, both being dependent on the presence of Na(+) ions in the external medium. Interestingly, heteroexchange only occurs in one preferred substrate orientation, i.e. with taurine transported inwards and aspartate outwards, suggesting a mechanism of transinhibition of aspartate uptake by intracellular taurine. Therefore, dEAAT2 is actually an aspartate/taurine transporter. Further studies of this protein are expected to shed light on the role of taurine as a candidate neuromodulator and cell survival factor in the Drosophila nervous system.

Ecdysone receptor-dependent gene regulation mediates histone poly(ADP-ribosyl)ation

While the ecdysone dependency of puff formation in giant polytene chromosomes from fly salivary glands has been well documented, the molecular mechanisms underlying this process remain unknown. However, it does appear to involve chromatin remodeling and modification mediated by ecdysone receptor (EcR). As Drosophila poly(ADP-ribose) polymerase (dPARP) has recently been reported to be involved in ecdysone-induced puff formation, we decided to test the possible role of dPARP in ligand-induced dEcR transactivation in an insect system. dPARP co-activated the ligand-induced transactivation function of EcR in the insect cell line S2, and appeared to physically interact with EcR in a ligand-dependent manner. ChIP analysis of an EcR target gene promoter revealed ligand-dependent recruitment of dPARP with poly(ADP-ribosyl)ation of histones in the EcR binding site and, surprisingly, also in a distal region of the promoter. Our results indicated that EcR-mediated gene regulation may be coupled with chromatin modification through poly(ADP-ribosyl)ation.

Anomalous Behavior of Phonon Diffusiveness Coefficient of Cubic Compounds with Anomalous Elastic Properties

The phonon diffusiveness coefficient D related to scattering of phonons by point mass defects embedded in cubic crystalline media can be written as product of diffusiveness coefficient for a corresponding reference isotropic medium D is , and the dimensionless coefficient $$\widetilde D$$ which depends on two dimensionless elastic parameters s 2 , s 3. This coefficient is studied in the triangle–shaped region of plane (s 2 ,s 3 ) in which cubic elastic crystalline media are mechanically stable. As a function of s 2 and s 3 the coefficient $$\widetilde D$$ is nonmonotoneous and behaves singularly on the line s 2 = s 3. The underlying physical mechanism is considered.

The mode of cell death associated with cavitation in teratocarcinoma-derived embryoid bodies

Cell death occurring in embryoid bodies derived from the embryonal carcinoma cell line, PSA4, which undergo cavitation, and in those from the related cell line S2, which do not undergo cavitation, was classified as apoptosis or necrosis by ultrastructural criteria. Both modes of cell death were seen in PSA4 embryoid bodies while apoptosis alone was seen in S2 embryoid bodies. No significant difference was found between PSA4 and S2 embryoid bodies either in apoptotic incidence score or in the spatial distribution of apoptotic events. We therefore conclude that although apoptosis and tissue modelling coexist in PSA4 embryoid bodies, necrosis rather than apoptosis is causally related to formation of the cavity.