Coat protein-mediated resistance against an Indian isolate of the Cucumber mosaic virus subgroup IB in Nicotiana benthamiana

Coat protein (CP) -mediated resistance against an Indian isolate of the Cucumber mosaic virus (CMV) subgroup IB was demonstrated in transgenic lines of Nicotiana benthamiana through Agrobacterium tumefaciens-mediated transformation. Out of the fourteen independently transformed lines developed, two lines were tested for resistance against CMV by challenge inoculations. The transgenic lines exhibiting complete resistance remained symptomless throughout life and showed reduced or no virus accumulation in their systemic leaves after virus challenge. These lines also showed virus resistance against two closely related strains of CMV. This is the first report of CP-mediated transgenic resistance against a CMV subgroup IB member isolated from India.     

cDNA microarray profiles of canine mammary tumour cell lines reveal deregulated pathways pertaining to their phenotype

Mammary cancer is the most common type of cancer in female dogs with a lifetime risk of over 24% when dogs are not spayed. The elucidation of the complete canine genome opens new areas for development of cancer therapies. These should be tested first by in vitro models such as cell lines. However, to date, no canine mammary cell lines have been characterized by expression profiling. In this study, canine mammary tumour cell lines with histologically distinct primary tumours of origin were characterized using a newly developed canine cDNA microarray. Comparisons of gene expression profiles showed enrichment for distinct biological pathways and were related to biological properties of the cell lines such as growth rate and in vitro tumourigenicity. Additionally, gene expression profiles of cell lines also showed correspondence to their tumour of origin. Major differences were found in Wnt, cell cycle, cytokine/Rho-GTPase, alternative complement and integrin signalling pathways. Because these pathways show an overlap at the molecular level with those found in human breast cancer, the expression profiling of spontaneous canine mammary cancer may also function as a biological sieve to identify conserved gene expression or pathway profiles of evolutionary significance that are involved in tumourigenesis. These results are the basis for further characterization of canine mammary carcinomas and development of new therapies directed towards specific pathways. In addition these cell lines can be used to further investigate identified deregulated pathways and characterize until now unannotated genes.     

Isolation and structural identification of complex feruloylated heteroxylan side-chains from maize bran

Three complex heteroxylan side-chains acylated with ferulate and one arabinosyl ester of p-coumaric acid have been isolated from maize bran insoluble fibre after acidic hydrolysis and fractionation by gel permeation chromatography and semi-preparative RP-HPLC. The complete structural elucidation of all isolated compounds was achieved by 1D/2D NMR spectroscopy and HPLC-MS in combination with methylation analysis. The absolute configuration of the carbohydrate constituents was determined by chiral GC after acidic hydrolysis and trifluoroacetylation. The identified feruloylated tetrasaccharides alpha-d-xylopyranosyl-(1-->3)-alpha-l-galactopyranosyl-(1-->2)-beta-d-xylopyranosyl-(1-->2)-5-O-trans-feruloyl-l-arabinofuranose (FAXGX) and alpha-d-galactopyranosyl-(1-->3)-alpha-l-galactopyranosyl-(1-->2)-beta-d-xylopyranosyl-(1-->2)-5-O-trans-feruloyl-l-arabinofuranose (FAXGG) are the most complex heteroxylan side-chains from maize bran that have been isolated to date. The isolated trisaccharide alpha-l-galactopyranosyl-(1-->2)-beta-d-xylopyranosyl-(1-->2)-5-O-trans-feruloyl-l-arabinofuranose (FAXG) contributes to the complexity of heteroxylan side-chains from maize bran and 5-O-trans-p-coumaroyl-l-arabinofuranose represents the first p-coumaroylated heteroxylan side-chain isolated from cereal grains. Complex feruloylated heteroxylan side-chains are possibly, like ferulate cross-linking of the heteroxylans and binding of heteroxylans to lignin, a factor contributing to limited enzymatic degradation of fibre.     

不同品系番茄对番茄刺皮瘿螨生长发育的影响

为了弄清楚不同番茄品种对番茄刺皮瘿螨Aculops lycopersici (Massee)的抗感性程度,通过田间调查、室内盆栽接螨和离体培养等方法,考察了12个番茄品种（系）（多茸毛类YZ618和YZ619;少茸毛类YZ419, YZ507和YZ504;野生品系YZ7和YZ5 叶黄类YZ401;常规品系YZ406,YZ412,YZ413和YZ515）上番茄刺皮瘿螨的种群发育情况。结果表明：番茄刺皮瘿螨在不同番茄品种（系）上的种群密度有明显差异,野生品系YZ7及多茸毛品系YZ618和YZ619上较低,少茸毛品系YZ504,YZ507和YZ419较高。不同番茄品种（系）可能是通过影响螨的存活率和产卵能力来影响在品种（系）上的种群发展。离体培养观察发现,番茄刺皮瘿螨的存活率在少茸毛品系YZ504和YZ507上最高,其次是品系YZ419,野生品系YZ7上最低。在YZ504上的产卵量最大,YZ419和YZ507次之,YZ7最小。根据实验种群参数判断,野生品系YZ7及多茸毛品系YZ618和YZ619感螨程度低,为抗性品系; 少茸毛品系YZ504,YZ419和YZ507感螨程度高,为感螨品系。     

The mycotoxin fumonisin B1 inhibits eukaryotic protein synthesis: in vitro and in vivo studies

Inhibitory action of Fumonisin B₁ (FB₁) on eukaryotic protein synthesis was investigated, both in animal and plant system, and was compared with cycloheximide. Inhibitory effect of FB₁ was monitored in the TCA precipitable proteins of rabbit reticulocyte lysates exposed to various concentrations of the mycotoxin (0.0013–2.76 mM), using ³⁵ S-methionine as a tracer. FB₁ inhibited the protein synthesis by 6%, at 0.0013 mM and by 88%, at a higher concentration of 2.76 mM. Cycloheximide at a concentration of 0.355 mM was found to inhibit protein synthesis by 88%. Inhibitory action of FB₁ (1 mg kg⁻¹ body mass and a higher dose of 10 mg kg⁻¹ body mass) or cycloheximide (10 mg kg⁻¹ body mass; positive controls), injected intra-peritoneally into BALB/c mice was studied using ¹⁴C-l-Leucine as a tracer. FB₁ at lower dose of 1 mg kg⁻¹ body mass inhibited protein synthesis in liver by 8% and at a higher dose of 10 mg kg⁻¹ body mass by 38% in the BALB/c mice, when compared to cycloheximide which inhibited protein synthesis by 61%. The effects of FB₁ on protein synthesis in plant system was studied in germinated maize seedlings exposed to FB₁ at 0.9 μM, 0.009 mM and 0.09 mM concentrations, using ¹⁴C-l-Leucine as a tracer. Fumonisin B₁ at low, middle, and higher concentrations (0.9 μM, 0.009 mM, and 0.09 mM) inhibited protein synthesis in the seedlings by 4%, 12% and 22%, respectively. The inhibitory effects of FB₁ on the protein synthesis in the animal system in vitro and in vivo conditions, and in the plant system were found to be dose-dependent, though it was less potent compared to cycloheximide.     

Maize seedling morphology and defence hormone profiles,but not herbivory tolerance,were mediated by domestication and modern breeding

We addressed whether Zea seedling morphology relevant to performance, defence hormone profiles and tolerance of a phloem‐feeding, specialist herbivore were affected by two processes, plant domestication and modern breeding. Domestication effects were inferred through comparisons between Balsas teosintes (Zea mays parviglumis) and landrace maizes (Z. mays mays), and modern breeding effects through comparisons between landrace maizes and inbred maize lines. Specifically, we compared seedling forms (a composite measure of leaf length, average stem diameter, shoot wet weight, shoot dry weight, total root length, root wet weight, and root dry weight), shapes (forms scaled by seedling dry weight, a proxy for seedling size), and defence hormone profiles among Balsas teosinte and landrace and inbred line maizes, exposed or unexposed to feeding by Dalbulus maidis. Our results suggested that domestication as well as modern breeding strongly mediated both seedling form and shape. Form was more similar between landrace and inbred maize than between Balsas teosinte and landrace maize, suggesting that domestication affected seedling form more than modern breeding. In contrast, shape was more similar between Balsas teosinte and landrace maize than between landrace and inbred maizes, suggesting that modern breeding affected seedling shape more than domestication. Additionally, seedling shoot : root ratios appeared to have been mediated by domestication, but not by modern breeding. In broad terms, individual seedling structures relevant to seedling ecology in wild or managed environments, such as leaf and root lengths, and shoot and root masses, were enlarged with domestication and reduced with modern breeding. Herbivory did not affect seedling shape, but had a weak effect on form so that seedlings were slightly larger in the absence versus presence of D. maidis. Also, both domestication and modern breeding seem to have mediated seedling hormone profiles, with breeding more strongly mediating profiles than domestication. Jasmonic acid isoleucine (JA‐Ile) and salicylic acid (SA) were induced by herbivory in both teosinte and maize. The hormone profiles assays collectively suggested that domestication and modern breeding altered constitutive levels of SA, abscisic acid and JA‐related (JA‐Ile and oxo‐phytodienoic acid) hormone levels in seedlings, particularly by increasing the levels of SA and decreasing those of JA‐related hormones. Altogether, our results suggested that maize domestication and modern breeding significantly altered seedling form, shape, ecologically relevant morphological traits (e.g. leaf and root lengths, and shoot and root masses) and hormonal defences, but not tolerance of D. maidis herbivory.     

Potential anti-proliferative agents from 1,4-benzoxazinone-quinazolin-4(3H)-one templates

A novel synthetic protocol has been developed for the synthesis of 1,4-benzoxazinone-acetylphenylallyl quinazolin-4(3H)-one hybrids 7a–n by employing Pd-catalyzed CH arylation in presence of 5–10% phosphine ligand in good to excellent yields and evaluated for their anti-proliferative activity against three cancer cell lines such as A549 (lung), HeLa (cervical), MDA-MB-231 (breast). Compounds 7d, 7f, 7l and 7n exhibited promising anti-proliferative activity with GI₅₀ values ranging from 0.37 to 2.73?µM respectively against A549, HeLa, and MDA-MB-231, while compound 7f showed significant activity against MDA-MB-231 with GI₅₀ value 0.58?µM, 7j showed significant activity against A549 with GI₅₀ value 0.32?µM and 7l showed significant activity against HeLa with GI₅₀ value 0.37?µM. This is the first report on the synthesis and in vitro anti-proliferative evaluation of 1,4-benzoxazinone-acetylphenylallyl quinazolin-4(3H)-one hybrids.     

Estimation of FPAR and FPAR profile for maize canopies using airborne LiDAR

FPAR (fraction of photosynthetically active radiation) and FPAR profile (vertical FPAR distribution) are important parameters for characterizing the vegetation growth status and studying global climate change. Few studies have been carried out to estimate FPAR and FPAR profile using waveform LiDAR data. This research explored the potential of airborne small-footprint full-waveform LiDAR in the estimation of FPAR and FPAR profile of the maize canopy in Huailai County of Hebei Province, China. First, the maize growing area was identified by a simple decision tree model. Second, raw waveform data were processed to extract LiDAR-derived energy ratio and energy ratio profile. Third, FPAR and FPAR profile were estimated from LiDAR-derived metrics. Finally, we analyzed the FPAR and FPAR profile estimation results and assessed the model validity using the leave-one-out cross-validation (LOOCV) method. The comparative analyses found that the LiDAR-derived energy ratio profile and field-measured FPAR profile had the same trend and similar change rate for all maize layers. The accuracy assessments indicated that the FPAR and FPAR profile were estimated well by the LiDAR waveform data, with the high R² (0.90 for the whole canopy, and 0.95, 0.90, 0.93, 0.92, and 0.97 for layers 1–5) and low RMSEs (0.042 for the whole canopy, and 0.033, 0.035, 0.039, 0.043, and 0.044 for layers 1–5). The spatial distribution map of FPAR was produced to describe the maize growth status of the whole study area, and the map showed that the FPAR distributed relatively uniformly. This study suggested that airborne small-footprint full-waveform LiDAR was useful in accurately measuring FPAR and FPAR profile of the maize canopy and in effectively mapping the maize FPAR spatial distribution.     

Molecular characterization of segments S7 to S10 of a southern rice black-streaked dwarf virus isolate from maize in northern China

Southern rice black-streaked dwarf virus (SRBSDV) is a novel Fijivirus prevalent in rice in southern and central China, and northern Vietnam. Its genome has 10 segments of double-stranded RNA named S1 to S10 according to their size. An isolate of SRBSDV, JNi4, was obtained from naturally infected maize plants from Ji’ning, Shandong province, in the 2008 maize season. Segments S7 to S10 of JNi4 share nucleotide identities of 72.6%–73.1%, 72.3%–73%, 73.9%–74.5% and 77.3%–79%, respectively, with corresponding segments of Rice black-streaked dwarf virus isolates, and identities of 99.7%, 99.1%–99.7%, 98.9%–99.5%, and 98.6%–99.2% with those of SRBSDV isolates HN and GD. JNi4 forms a separate branch with GD and HN in the phylogenetic trees constructed with genomic sequences of S7 to S10. These results confirm the proposed taxonomic status of SRBSDV as a distinct species of the genus Fijivirus and indicate that JNi4 is an isolate of SRBSDV. Shandong is so far the northernmost region where SRBSDV is found in China.