Changes in phosphatidylinositol 3-kinase 55 kDa gamma expression and subcellular localization may be caspase 6 dependent in paraquat-induced SH-SY5Y apoptosis

The neurotoxin paraquat (PQ) causes apoptosis of dopaminergic neurons in mammalian cell culture and animal models, mimicking an important pathological feature of Parkinson's disease (PD). The phosphoinositide 3-kinase (PI3K)/Akt pathway is critical for several major survival signals in central nervous system neurons. Phosphatidylinositol 3-kinase 55 kDa gamma (p55PIK) is a regulatory subunit of PI3Ks with important roles in cell proliferation, antiapoptosis, and cell cycle progression. However, p55PIK involvement in mechanisms regarding progression and maintenance of neurodegenerative diseases is largely undetermined. We used PQ-induced apoptosis in human dopaminergic SH-SY5Y cells to investigate the association between p55PIK expression levels, subcellular location, and apoptosis. p55PIK expression was reduced in SH-SY5Y cells and p55PIK messenger RNA and protein expression levels were decreased after PQ treatment. Apoptosis induced by PQ was associated with caspase activation and decreased p55PIK expression. Restoration of p55PIK expression was observed after coincubation with a caspase inhibitor. Overexpressed full-length p55PIK in SH-SY5Y and human embryonic kidney 293 cells showed specific distribution in the nucleus and was cleaved in vitro by recombinant caspase 6 (C6), but not C3 and C7. A p55PIK construct lacking 24 N-terminal amino acids (N24) was tested for the presence of a potential C6-recognizable sequence and was found to express its proteins outside the nucleus. The results suggest that p55PIK may be involved in PQ-induced apoptosis signal transduction and that N24 is crucial for p55PIK subcellular localization. Thus, p55PIK could be a substrate of activated C6 during apoptosis, leading to loss of original biological functions and redistribution to disturb cell cycle progression.

A conserved extraordinarily long serine homopolymer in Dictyostelid amoebae

Eukaryotic protein sequences often contain amino-acid homopolymers that consist of a single amino acid repeated from several to dozens of times. Some of these are functional but others may persist largely because of high expansion rates due to DNA slippage. However, very long homopolymers with over a hundred repeats are very rare. We report an extraordinarily long homopolymer consisting of 306 tandem serine repeats from the single-celled eukaryote Dictyostelium discoideum, which also has a multicellular stage. The gene has a paralog with 132 repeats and orthologs, also with high serine repeat numbers, in various other Dictyostelid species. The conserved gene structure and protein sequences suggest that the homopolymer is functional. The high codon diversity and very poor alignment of serine codons in this gene between species similarly indicate functionality. This is because the serine homopolymer is conserved despite much DNA sequence change. A survey of other very long amino-acid homopolymers in eukaryotes shows that high codon diversity is the rule, suggesting that these too may be functional.

Fine mapping of qhir1 influencing in vivo haploid induction in maize

Production of haploids by the in vivo haploid induction method has now become routine for generating new inbred lines in maize. In previous studies, a major quantitative trait locus (QTL) (qhir1) located in bin 1.04 was detected, explaining up to 66 % of the genotypic variance for haploid induction rate (HIR). Our objectives were to (1) fine-map qhir1 and (2) identify closely linked markers useful for marker-assisted breeding of new inducers. For this purpose, we screened a mapping population of 14,375 F2 plants produced from a cross between haploid inducer UH400 and non-inducer line 1680 to identify recombinants. Based on sequence information from the B73 reference genome, markers polymorphic between the two parents were developed to conduct fine mapping with these recombinants. A progeny test mapping strategy was applied to accurately determine the HIR of the 14 recombinants identified. Furthermore, F3 progeny of recombinant F2 plants were genotyped and in parallel evaluated for HIR. We corroborated earlier studies in that qhir1 has both a significantly positive effect on HIR but also a strong selective disadvantage, as indicated by significant segregation distortion. Altogether, we were able to narrow down the qhir1 locus to a 243 kb region flanked by markers X291 and X263.

CASP-9 gene functional polymorphisms and cancer risk: a large-scale association study plus meta-analysis

We investigated the association between CASP-9 polymorphisms and susceptibility to neoplasm. Fourteen studies with a total of 2733 neoplasm cases and 3352 healthy controls were included. Meta-analysis showed that the rs4645981 T allele and the rs4645981 T allele carrier were positively associated with neoplasm susceptibility [odds ratio (OR) = 1.43, 95% confidence interval (95%CI) = 1.12-1.81, P = 0.004; OR = 1.46, 95%CI = 1.10-1.93, P = 0.009, respectively]. However, the rs1052576 A allele, rs1052576 A carrier, rs2308941 T allele, and rs2308941 T carrier might decrease the risk of cancer (OR = 0.72, 95%CI = 0.58-0.89, P = 0.003; OR = 0.76, 95%CI = 0.63-0.92, P = 0.004; OR = 0.20, 95%CI = 0.09-0.45, P < 0.0001; OR = 0.21, 95%CI = 0.06-0.75, P = 0.02, respectively). There was no significant association between rs1263, rs1052571, rs2308950, rs4645978, rs4645980, rs4645982, and rs4646018 and cancer risk (all P > 0.05). In conclusion, this meta-analysis suggests that CASP-9 gene polymorphisms are involved in the pathogenesis of various cancers. The rs4645981 T allele and the rs4645981 T allele carrier might increase the risk of cancer, but the rs1052576 A allele, rs1052576 A carrier, rs2308941 T allele, and rs2308941 T carrier might be protective.

First Report of Impatiens necrotic spot virus on Hiemalis Begonia (Begonia × hiemalis) in Canada

Impatiens necrotic spot virus (INSV) is a member of the genus Tospovirus, and one of the prevalent viruses infecting ornamental plants, including begonia. Since the late 1980s, it has caused dramatic and unusual diseases on many flower crops, leading to considerable economic losses to the greenhouse floriculture industry (1). The western flower thrips, Frankliniella occidentalis (Pergande), is the only species currently known to vector INSV (1). In spring 2012, stunted plant growth and necrotic spots were observed on leaves of all Hiemalis begonias (Begonia × hiemalis Fotsch.) in a greenhouse in southwest Ontario, Canada. Initial symptoms were mosaic patterns, followed by necrotic spots on leaves, concentric rings, then necrotic areas on flowers, stem and vein necrosis, and finally stunting and burning of foliage similar to damage caused by sunburn or chemical injury. Thrips were observed colonizing nearby begonia plants. Leaf tissue from five symptomatic plants tested positive for INSV in a double-antibody sandwich (DAS)-ELISA with INSV-specific ImmunoStrips (Agdia Inc., Elkhart, IN). To confirm this, five of the leaf samples that were found to be positive for INSV in ELISA tests were mechanically inoculated to 10 plants of Hiemalis Begonia. Out of the 10 inoculated plants, eight produced necrotic local lesions and necrotic spots that are typical of INSV infection, followed by systemic infection of upper leaves 30 days after inoculation. The presence of INSV in the eight symptomatic plants was confirmed using the commercial INSV Pocket Diagnostic Kit (Forsite Diagnostics Ltd., York, UK) according to the manufacturer's instructions. Results showed that all eight symptomatic plants were positive for INSV. The other two plants were asymptomatic and tested negative for INSV. To further confirm the identity of this virus, total RNAs were isolated from symptomatic leave of begonia plants using TRIzol reagent (Invitrogen, Life Technologies Grand Island, NY) and amplified using reverse transcription (RT)-PCR analysis. A pair of primers was designed based on the consensus sequence of the N gene for a number of isolates retrieved from GenBank. These primers were INSV-F2286 (5'CCAAGCTCAACATGTTTAGC 3', nt positions 2286 to 2305 of AB109100) and INSV-R2604 (5'ACTGCATCTTGCCTATCCTT 3', nt positions 2664 to 2683 of AB109100). The expected amplification product of 398 bp was obtained, and was cloned into the vector pGEM-T Easy (Promega Corp., Madison, WI). Two clones were sequenced using the vector primer M13Forward. The sequences of these two clones were identical and the sequence was deposited in GenBank (Accession No. JX846907). BLAST analysis indicated that the sequence was 98 to 99% identical to INSV isolates from Japan (AB109100), the United States (D00914), and the Netherlands (X66972). To our knowledge, this is the first report of INSV infection in Begonia × hiemalis in Canada. This finding provides further evidence for the spread of the virus within North America. Further studies are required to determine the impact of INSV on the begonia industry in Canada and to determine viable management strategies, if necessary. Reference: (1) M. L. Daughtrey et al. Plant Dis. 81:1220, 1997.

Acute dietary zinc deficiency before conception compromises oocyte epigenetic programming and disrupts embryonic development

Recent findings show that zinc is an important factor necessary for regulating the meiotic cell cycle and ovulation. However, the role of zinc in promoting oocyte quality and developmental potential is not known. Using an in vivo model of acute dietary zinc deficiency, we show that feeding a zinc deficient diet (ZDD) for 3-5 days before ovulation (preconception) dramatically disrupts oocyte chromatin methylation and preimplantation development. There was a dramatic decrease in histone H3K4 trimethylation and global DNA methylation in zinc deficient oocytes. Moreover, there was a 3-20 fold increase in transcript abundance of repetitive elements (Iap, Line1, Sineb1, Sineb2), but a decrease in Gdf9, Zp3 and Figla mRNA. Only 53% and 8% of mature eggs reached the 2-cell stage after IVF in animals receiving a 3 and 5 days ZDD, respectively, while a 5 day ZDD in vivo reduced the proportion of 2-cells to 49%. In vivo fertilized 2-cell embryos cultured in vitro formed fewer (38%) blastocysts compared to control embryos (74%). Likewise, fewer blastocyst and expanded blastocyst were collected from the reproductive tract of zinc deficient animals on day 3.5 of pregnancy. This could be due to a decrease in Igf2 and H19 mRNA in ZDD blastocyst. Supplementation with a methyl donor (SAM) during IVM restored histone H3K4me3 and doubled the IVF success rate from 17% to 43% in oocytes from zinc deficient animals. Thus, the terminal period of oocyte development is extremely sensitive to perturbation in dietary zinc availability.

Meta-analysis demonstrates association of XRCC1 genetic polymorphism Arg399Gln with esophageal cancer risk in the Chinese population

We made a meta-analysis of the association between X-ray cross-complementing gene 1 (XRCC1) genetic polymorphism Arg399Gln and esophageal cancer (EC) risk. Statistical analysis was performed with the Review Manager version 4.2.8 software program and STATA version 11.0. We selected 16 case-control studies for this meta-analysis, including 3591 EC cases and 5752 controls. Overall, the Gln399 allele was not associated with EC risk, compared with the Arg399 allele in the populations included in the analysis. However, stratified analysis revealed that the Gln399 allele was associated with increased EC risk among the Chinese population in a recessive model [odds ratio (OR) = 1.42; 95% confidence interval (95%CI) = 1.07-1.90; P = 0.02 for heterogeneity] and by homozygote contrast (OR = 1.43; 95%CI = 1.05-1.96; P = 0.02 for heterogeneity), particularly for the tumor histology of squamous cell carcinoma (OR = 1.46; 95%CI = 1.10-1.95 for the recessive model and OR = 1.42; 95%CI = 1.03-1.95 for the homozygote contrast). We conclude that the XRCC1 Arg399Gln polymorphism has potential as a biomarker for EC susceptibility in the Chinese population, particularly for squamous cell carcinoma.

A literature-based systematic HuGE review and meta-analysis show that CASP gene family polymorphisms are associated with risk of lung cancer

The caspase (CASP) gene family is known to be involved in apoptosis, cytokine maturation, cell growth, and differentiation. A large number of single nucleotide polymorphisms (SNPs) in the CASP gene family have been increasingly recognized as important regulators in the development of lung cancer. However, this specific association is still controversial. In this Human Genome Epidemiology review and meta-analysis, we summarized the available evidence associating lung cancer with the CASP gene family. Seven studies, which included 1155 lung cancer cases and 1120 healthy controls, met the inclusion criteria and were included in our meta-analysis. In seven studies, 19 different SNPs have been studied in seven CASP genes, including CASP-1, -2, -5, -7, -8, -9, and -10. Meta-analysis results showed positive associations between heterozygote (A/G) of rs507879 in the CASP-5 gene, the T allele of rs12415607 in the CASP-7 gene, and the T allele and T carrier (C/T+T/T) of rs4645981 in the CASP-9 gene with lung cancer susceptibility [odds ratio (OR) = 1.83, 95% confidence interval (95%CI) = 1.07-3.12, P = 0.03; OR = 1.18, 95%CI = 1.02-1.37, P = 0.03; OR = 1.43, 95%CI = 1.12-1.81, P = 0.004; OR = 1.46, 95%CI = 1.10-1.93, P = 0.009; respectively]. However, we found that homozygote (G/G) of rs2227310 in the CASP-7 gene, del allele, heterozygote (ins/del), and del carrier (ins/del + del/del) of rs3834129 in CASP-8 could be protective factors for lung cancer (OR = 0.17, 95%CI = 0.14-0.21, P = 0.0003; OR = 0.83, 95%CI = 0.72-0.97, P = 0.02; OR = 0.74, 95%CI = 0.64-0.85, P < 0.0001; OR = 0.81, 95%CI = 0.71-0.93, P = 0.002; respectively). In conclusion, based on this meta-analysis, we suggest that SNPs in CASP-5, -7, -8, and -9 are associated with susceptibility to lung cancer.

Protective effect of the nitric oxide pathway in L-citrulline renal ischaemia-reperfusion injury in rats

To observe the protective effects of L-citrulline on the renal I/R injury and elucidate the mechanisms involved, 48 rats were randomized into eight groups: Group 1: sham operated; Group 2: I/R (45 min renal ischaemia and 24 h reperfusion); Group 3: I/R + L-citrulline (300 mg/kg, i.g.); Group 4: I/R + L-citrulline (600 mg/kg, i.g.); Group 5: I/R + L-citrulline (900 mg/kg, i.g.); Group 6: I/R + normal saline (NS, i.g.); Group 7: I/R + N sup ω nitro-L-arginine ester (L-NAME, 20 mg/kg, i.p.); Group 8: I/R + L-citrulline (900 mg/kg, i.g.) + L-NAME (20 mg/ kg, i.p.). At the end of the reperfusion period, serum was collected and the kidneys underwent histological and biochemical examinations. Our results showed that pre-treatment with L-citrulline (300, 600, and 900 mg/kg) significantly ameliorated the renal injury caused by I/R. Moreover, L-citrulline prevented induction of lipid peroxidation and increased the activity of superoxide dismutase and the levels of glutathione and nitric oxide. The I/R-induced decreases in total nitric oxide synthase activity, inducible nitric oxide activity, constitutive nitric oxide activity and endothelial nitric oxide protein expression in the renal cortex were significantly prevented. However, the L-citrulline-mediated protection was significantly antagonized by co-administration of L-NAME. These results suggested that L-citrulline administration exhibited significant protection against renal I/R injury. This protective effect, at least in part, via up-regulation of the endothelial nitric oxide protein expression and constitutive nitric oxide synthase activity, maintained production of nitric oxide at the basal level.

Dynamic-average Characteristics of Late Wave of Auditory Evoked Potentials for Synaptic Malfunction Rat Model

The aim of this study is to investigate dynamic characteristics of late wave of auditory evoked potentials (AEPs) in synaptic malfunction rat model. Two dynamic characteristics relative to cognitive function were investigated which are dynamic latency and dynamic amplitude of P1. Synaptic malfunction model was made by Sprague-Dawley rats via microinjecting beta-amyloid protein (A-beta) into hippocampal CA1 area of rat. Dynamic AEPs with high background noise were recorded for both model and normal rats in experiments. Dynamic late wave were taken from dynamic AEPs using third-order correlation and wavelet technology. The dynamic-average latency and the dynamic-average amplitude of P1 in a small time window (5s) were performed as dynamic index in this study, which remain most of dynamic information because the average window was very small. Then dynamic-average latency and the dynamic-average latency of P1 were compared between synaptic malfunction rat and normal group. The results of this study have demonstrated that: (1) the dynamic-average latency of P1 for model rats prolonged remarkably than control (P<0.01, alpha =0.05); (2) the dynamic-average amplitude of P1 for model rats increased remarkably than control(P<0.01,alpha =0.05). The conclusion is that dynamic-average latency and dynamic-average amplitude in the synaptic malfunction rats model has obvious difference with normal group.

Zinc depletion causes multiple defects in ovarian function during the periovulatory period in mice

Shortly before ovulation, the oocyte acquires developmental competence and granulosa cells undergo tremendous changes including cumulus expansion and luteinization. Zinc is emerging as a key regulator of meiosis in vitro, but a complete understanding of zinc-mediated effects during the periovulatory period is lacking. The present study uncovers the previously unknown role of zinc in maintaining meiotic arrest before ovulation. A zinc chelator [N,N,N',N'-tetrakis (2-pyridylmethyl) ethylenediamine (TPEN)] caused premature germinal vesicle breakdown and associated spindle defects in denuded oocytes even in the presence of a phosphodiesterase 3A inhibitor (milrinone). TPEN also potently blocked cumulus expansion by blocking induction of expansion-related transcripts Has2, Ptx3, Ptgs2, and Tnfaip6 mRNA. Both meiotic arrest and cumulus expansion were rescued by exogenous zinc. Lack of cumulus expansion is due to an almost complete suppression of phospho-Sma- and Mad-related protein 2/3 signaling. Consistent with a decrease in phospho-Sma- and Mad-related protein 2/3 signaling, TPEN also decreased cumulus transcripts (Ar and Slc38a3) and caused a surprising increase in mural transcripts (Lhcgr and Cyp11a1) in cumulus cells. In vivo, feeding a zinc-deficient diet for 10 d completely blocked ovulation and compromised cumulus expansion. However, 42.5% of oocytes had prematurely resumed meiosis before human chorionic gonadotropin injection, underscoring the importance of zinc before ovulation. A more acute 3-d treatment with a zinc-deficient diet did not block ovulation but did increase the number of oocytes trapped in luteinizing follicles. Moreover, 23% of ovulated oocytes did not reach metaphase II due to severe spindle defects. Thus, acute zinc deficiency causes profound defects during the periovulatory period with consequences for oocyte maturation, cumulus expansion, and ovulation.

Regulation of radiosensitivity by HDAC inhibitor trichostatin A in the human cervical carcinoma cell line Hela

Histone deacetylase (HDAC) inhibitors play an important role in inducing growth arrest, differentiation, and/or apoptosis in cancer cells. Given their ability to disrupt critical biological processes in cancer cells, these agents are emerging as potential therapeutics for cancer. Recently, it has been identified that HDAC inhibitors can also efficiently enhance the radiation sensitivity of cells, both in vitro and in vivo. In this study, we investigated whether the potent HDAC inhibitor, Trichostatin A, modulates the radiation sensitivity of the human cervical carcinoma cell line Hela under hypoxic conditions. We concluded that TSA could significantly inhibit the proliferation of Hela cells in a dose-and time-dependent manner under normoxic and hypoxic conditions. Hypoxia resulted in the cervical carcinoma Hela cells resistant to TSA. The findings from clonogenic survival assays indicate that incubation with TSA for 24 hours prior to irradiation enhances the radiation sensitivity of Hela cells under hypoxic conditions. More generally, we found Hela cells under hypoxic conditions treated with TSA could significantly down-regulate the expressions of HIF-1alpha and VEGF proteins. Taken together, our results demonstrated that TSA acts as a powerful radiosensitizer in Hela cells under hypoxic conditions probably by down-regulated expression of HIF-1alpha and VEGF proteins.

Elective neck dissection in papillary thyroid carcinoma patients

BACKGROUND

This study was designed to review the diagnostic performance of cervical lymph node metastases for assessment of elective neck dissection in papillary thyroid carcinoma patients and to determine the technique (using Methylene blue dye) that demonstrated the highest success rate with regard to the detection rate and sensitivity.

METHODS

Preoperative 24 h, 1 mL of 1.0% methylene blue was injected into the parenchyma surrounding the primary tumor with ultrasound guidance by a 27-gauge needle. Intra-operative lymph nodes that were stained blue and/or having afferent lymphatic channels stained blue were also considered to be excised. All stained blue nodes were defined by levels, number, site and were sent for frozen and permanent section histologic analysis.

RESULTS

For the 132 patients who underwent methylene blue dye, 1373 lymph nodes were removed. 7 lymph nodes had negative dye results but, in the end, had metastatic lymph nodes. 120 lymph nodes had both negative dye and lymph node results. The number of blue-dye lymph nodes was 1246 and the number of pathology metastatic nodes was 1079, so the pathological diagnose accordance rate was 87.8 percent. The nodal metastases often occur at level VI, IV, III, then in level II, and less in level I and V.

CONCLUSIONS

This method using methylene blue dye is feasible technically and is safe, and the findings correlate with cervical lymph node status. According to the pattern of blue dye lymph nodes and frozen-section histologic analysis, performing elective neck dissection is a reliable, safe surgical procedure for PTC.

Inactivation of the von Hippel-Lindau tumor suppressor leads to selective expression of a human endogenous retrovirus in kidney cancer

A human endogenous retrovirus type E was recently found to be selectively expressed in most renal cell carcinomas (RCC). Importantly, antigens derived from this provirus are immunogenic, stimulating cytotoxic T-cells that kill RCC cells in vitro and in vivo. Here we show HERV-E expression is restricted to the clear cell subtype of RCC (ccRCC) characterized by an inactivation of the von Hippel-Lindau (VHL) tumor suppressor gene with subsequent stabilization of hypoxia-inducible transcription factors HIF-1α and -2α. HERV-E expression in ccRCC linearly correlated with HIF-2α levels and could be silenced in tumor cells by either transfection of normal VHL or siRNA inhibition of HIF-2α. Using chromatin immunoprecipitation, we demonstrated that HIF-2α can serve as transcriptional factor for HERV-E by binding with HIF response elements (HRE) localized in the proviral 5′LTR. Remarkably, the LTR was found to be hypomethylated only in HERV-E-expressing ccRCC while other tumors and normal tissues possessed a hypermethylated LTR preventing proviral expression. Taken altogether, these findings provide the first evidence that inactivation of a tumor suppressor gene can result in aberrant proviral expression in a human tumor and give insights needed for translational research aimed at boosting human immunity against antigenic components of this HERV-E.

Diffuse alveolar hemorrhage in systemic lupus erythematosus: a retrospective study in China

The objective of this study was to determine the clinical features of systemic lupus erythematosus (SLE) patients with diffuse alveolar hemorrhage (DAH). The medical records of 29 patients with DAH among 2133 SLE patients admitted to Peking Union Medical College Hospital from January 2004 to January 2009 were reviewed in this retrospective study. It was found that hypoxemia (100%), dyspnea (90%), cough (79%) and fever (72%), rather than hemoptysis (66%), were the most common symptoms. The most common extrapulmonary presentation was renal involvement (90%). In about 60% of patients nosocomial infection was also present. The mean drop in hemoglobin was 32 ± 10.9 g/l. Mean Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) was 17 ± 9. All patients received high-dose corticosteroid therapy and most were also given immunosuppressive agents. Rates of concomitant nosocomial infection and mechanical ventilation in non-survivors were higher than those of survivors (p < 0.05). DAH is a rare and catastrophic event in SLE. DAH can occur at any stage of the disease course; it usually occurs in patients with active SLE, and is frequently complicated by lupus nephritis. Some patients may have no hemoptysis. Early aggressive management with high-dose steroids and cyclophosphamide is advocated.

Localization of phosphorylated SMAD proteins in granulosa cells, oocytes and oviduct of female mice

SMAD signaling is essential for follicular development. The distribution of activated (phosphorylated) SMADs during folliculogenesis has not been described in detail. The present results indicate that oocytes from preantral and antral follicles contain the mRNA for the receptor regulated Smads (-1, -2, -3, -5 and -9), Smad4 (co-SMAD), and Smad6 and Smad7 (inhibitory SMADs). Levels of Smad5, Smad6 and Smad7 mRNA decreased in fully-grown oocytes compared to growing oocytes. Immunostaining for pSMAD1/5/9, pSMAD2 and pSMAD3 was evident in oocytes from primordial, primary, secondary and antral follicles. We also observed substantial staining for pSMADs in intact fully-grown oocytes from antral follicles. In granulosa cells, immunostaining for both pSMAD2/3 and pSMAD1/5/9 was apparent in preantral granulosa cells from primordial to secondary follicles. In antral follicles, immunostaining for pSMADs became more intense in the cumulus cells surrounding the oocyte. Immunostaining for pSMAD2 and pSMAD1/5/9 was also apparent in the epithelium lining of the oviduct. Clearly, oocytes, preantral granulosa cells, cumulus cells and the epithelium of the oviduct are major targets of SMAD-mediated pathways in female reproductive tissues. The finding that pSMAD pathways are active in oocytes raises new questions regarding the role of TGF-beta superfamily members in directly promoting oocyte development. The extent to which defects in pSMAD signaling in oocytes or the oviduct contribute to infertility in humans or animals remains an open question.

A herbicide-resistant ACCase 1781 Setaria mutant shows higher fitness than wild type

It is often alleged that mutations conferring herbicide resistance have a negative impact on plant fitness. A mutant ACCase1781 allele endowing resistance to the sethoxydim herbicide was introgressed from a resistant green foxtail (Setaria viridis (L.) Beauv) population into foxtail millet (S. italica (L.) Beauv.). (1) Better and earlier growth of resistant plants was observed in a greenhouse cabinet. (2) Resistant plants of the advanced BC7 backcross generation showed more vigorous juvenile growth in the field, earlier flowering, more tillers and higher numbers of grains than susceptible plants did, especially when both genotypes were grown in mixture, but their seeds were lighter than susceptible seeds. (3) Field populations originating from segregating hybrids had the expected allele frequencies under normal growth conditions, but showed a genotype shift toward an excess of homozygous resistant plants within 3 years in stressful conditions. Lower seed size, lower germination rate and perhaps unexplored differences in seed longevity and predation could explain how the resistant plants have the same field fitness over the whole life cycle as the susceptible ones although they produce more seeds. More rapid growth kinetics probably accounted for higher fitness of the resistant plants in adverse conditions. The likelihood of a linkage with a beneficial gene is discussed versus the hypothesis of a pleiotropic effect of the ACCase resistance allele. It is suggested that autogamous species like Setaria could not develop a resistant population without the help of a linkage with a gene producing a higher fitness.

Growth inhibition of Microcystis aeruginosa by white-rot fungus Lopharia spadicea

Harmful cyanobacterial blooms cause water deterioration and threaten human health. It is necessary to remove harmful cyanobacteria with useful methods. A bio-treatment may be one of the best ways to do this. A strain of specific white-rot fungus, Lopharia spadicea, with algicidal ability was isolated. Its algicidal ability on algae under various conditions was determined using three main influence factors: initial chlorophyll-a content, initial pH, and algal cell mixture. The result showed that the chlorophyll-a content of Microcystis aeruginosa FACHB-912, Oocystis borgei FACHB-1108, and Microcystis flos-aquae FACHB-1028 decreased from 798+/-13, 756+/-40, and 773+/-24 microg/L to 0 within 39 h. L. spadicea could also remove more than 95% chlorophyll-a when initial chlorophyll-a content increased from 397+/-13 to 2,132+/-4 microg/L. Moreover, the strain has great removal ability under a broad initial pH range of 5.5 to 9.5. The chlorophyll-a content of the three algal strain mixtures decreased from about 672+/-23 microg/L to 0 within 45 h. After superoxide dismutase (SOD) and malondialdehyde (MAD) were assessed in a co-culture of L. spadicea, it was observed that an increase in MAD content was correlated with the decrease in chlorophyll-a content of M. aeruginosa FACHB-912. This result suggested that the algae was not only greatly inhibited but also severely damaged by the fungus.