Construction of a DNA library from chromosome 4 of rice （Oryza sativa） by microdissection

A simple method to create a chromosome-specific DNA librqary of rice,including microdissection,amplification,charterization and cloning,is described.Rice chromosome 4 from a metaphase cell has been isolated and amplified by the Linker Adapter PCR (LA-PCR).The PCR products were labeled as probes with DIG-11-dUTP using the random priming method.Southern blot analysis with rice genomic DNA and specific RFLP markers demonstrated that the PCR products were derived from rice chromosome 4.A large library comprising over 100,000 recombinant plasmid microclones from rice chromosome 4 was constructed.Colony hybridization showed that 58% of the clones contained single or low-copy sequences and 42% contained repetitive sequences.The size of inserts generated by PCR ranged from 140bp to 500bp.This method will facilitate cloning of the specific chromosome DNA markers and important genes of rice.     

Candidate genes of hypertension with defective environmental expression

Previous studies in our laboratory have demonstrated that the thermosensitivity locus cosegregates with blood pressure and that the elevated expression and restriction fragment length polymorphism of HSP70 gene are associated with hypertension.Cell protection against environmental stressors such as heat and chemicals is often accompanied by up-regulated expression of a wide spectrum of heat shock genes(HSP).To further investigate the interrelation between HSP expression and blood pressure regulation,we employed an effective method of cloning 2 potential hypertension-related HSPs.Synthetic oligonucleotides corresponding either to a highly-conserved region of the known HSP family or a repetitive sequence in the proteinencoding gene were used as target primers for polymerase chain reaction(PCR).cDNA prepared from heat-stressed and non-stressed vascular smooth muscle cells(VSMC)of Brown Norway rats(BN.1x)and spontaneously hypertensive rats(SHRp) respectively served as template in the reaction.The PCR products were subsequently analyzed in a single-stranded conformational polymorphism(SSCP) electrophoresing system.Differential gene expression in BN.1x and SHRp was seen on autoradiographs of SSCP gel by comparing the migration patterns of PCR-amplified DNA fragments.Using this technique,we also found that HSP27 and a new member of the large HSP gene family were differentially expressed in BN.1x and SHRp VSMC.     

Processing Pisum sativum seed storage protein precursors in vitro

The profile of polypeptides separated by SDS-PAGE from seed of major crop species such as pea(Pisum sativum) is complex,resulting from cleavage (processing) of precursors expressed from multiple copies of genes encoding vicilin and legumin,the major storage globulins.Translation in vitro of mRNAs hybridselected from mid-maturation pea seed RNAs by defined vicilin and legumin cDNA clones provided precursor molecules that were cleaved in vitro by a cell-free protease extract obtained from similar stage seed;the derived polypeptides were of comparable sizes to those observed in vivo.The feasibility of transcribing mRNA in vitro from a cDNA clone and cleavage in vitro of the derived translation products was established for a legumin clone,providing a method for determining polypeptide products of an expressed sequence.This approach will also be useful for characterising cleavage site requirements since modifications an readily be introduced at the DNA level.     

Hitching a ride to the top: peroxisomes fuel cilium with cholesterol

正Primary cilium, which protrudes from the cell, is a microtubule-based structure ensheathed by a highly specialized plasma membrane (PM). It serves as a signaling hub for sensing and transducing various external stimuli including fluids, light, odorants as well as extracellular molecules.     

Structural and Functional Damage Caused by Boron Deficiency in Sunflower Leaves

Boron deficiency induced a dramatic inhibition in sunflower plant growth, shown by a reduction in dry mass of roots and shoots of plants grown for 10 d in nutrient solution supplied with 0.02 μM B. This low B supply facilitated the appearance of brown purple pigmentation on the plant leaves over the entire growth period. Compared to B-sufficient (BS) leaves, leakage from B-deficient (BD) leaves was 20 fold higher for potassium, 38 fold for sucrose, and 6 fold for phenolic compounds. High level of membrane peroxidation was detected by measuring peroxidase activities as well as peroxidative products in BD sunflower plants. Soluble and bound peroxidase activities measured in BD thylakoid membranes were accelerated two fold compared to those detected in BS-membranes. No detectable change in soluble peroxidase activity in roots whereas a 4 fold stimulation in bound peroxidase activity was detected. Thylakoid membranes subjected to low B supply showed enhancement in lipoxygenase activity and malondialdehyde (MDA) content in parallel with 40 and 30 % decrease of linoleic and linolenic acid contents (related to total unsaturated fatty acids). A slower rate of Hill reaction activity (40 %) and a suppressed flow of electron transfer of the whole chain (30 %) were detected in BD thylakoid membranes. This reduction was accompanied with a decline in the activity of photosystem 2 shown by a diminished rate of oxygen evolution (42 %) coupled with a quenching (27.5 %) in chlorophyll a fluorescence emission spectra at 685 nm (F₆₈₅). Thus B is an important element for membrane maintenance, protection, and function by minimizing or limiting production of free oxygen radicals in thylakoid membranes of sunflower leaves. This revised version was published online in June 2006 with corrections to the Cover Date.     

Garrulax milnei milnei,a taxon little known in Chinese ornithology

As early as 1874,the French scientist Père A.David introduced to science a new bird species,Trochalopteron milnei,described as:"Ressemblant au T.formosum du Setchouan,mais ayant le dessus de la tête couleur de cannelle ou d’amadou,et la région parotique blanche"(David,1874).The bird skin that Père David collected,and so far deposited in Muséum National d’Histoire Naturelle in Paris,was from"Koaten of W Fo-kien",in the current Chinese romanization system,Koaten is spelt as Guadun and Fo-kien spelt as Fujian.Then,spelling of the specific name of the bird was given as"milni"by David(1875),David and Oustalet(1877),and La Touche(1899,1925–1930).The bird is now usually known as Garrulax milnei milnei.However,Collar and Robson(2007)resurrected the genus Trochalopteron,and this is also being supported by Luo et al.(2009)as well as by Dickinson and Christidis(2014),but Bird Life still uses Garrulax(Bird Life,2015).     

A diet-induced type 2 diabetes model in Drosophila

正Dear Editor.Type 2 diabetes has become a global epidemic.It is a disease characterized by insulin resistance and relative insulin deficiency,resulting in hyperglycemia and various physiological and metabolic abnormalities.Besides genetic risk factors,inappropriate life styles,such as lack of physical activity and imbalanced diet,also contribute to the development of type 2diabetes in human (Jia et al.,2019).Animal models of type 2diabetes are of great value to understand its underlying mechanisms as well as to develop and evaluate potential diagnostic and therapeutic options (Kleinert et al.,2018).The     

中国新记录——次花角跳小蜂属

Metablastothrix was originally published as a subgenus of Blastothrix by Sugonjaev (1964). Sugonjaev and Babaev (1978) raised Metablastothrix to generic rank and placed it in the tribe Microteryini (Encyrtinae), subtribe Syrphophagina. Sugonjaev and Trjap…     

Identification of potential cross-protective epitope between a new type of coronavirus(2019-nCoV) and severe acute respiratory syndrome virus

Recently,a new type of unknown virus causing severe acute res-piratory infection was reported in Wuhan city,Hubei province,China(WHO,2020b).Infection of this virus was first reported in December 2019,and origin of the virus was traced back to a large seafood/wide animal market in Wuhan city.The serious clinical symptoms of the viral infection,including fever,dry cough,dys-pnea,and pneumonia,may result in progressive respiratory failure and even death.Moreover,the quick spread of the virus has caused an epidemic in China,as well as infection cases worldwide.The whole-genome sequence of Wuhan new virus(WH-Human_.1)was first released on January 10,2020(Zhang,2020),followed by additional ones released in Global Initiative on Sharing All Influ-enza Data(GISAID)(Shu and McCauley,2017).Later,this new virus was determined and announced as a new type of coronavirus(CoV;2019-nCoV)by the World Health Organization(WHO,2020a).     

Transposon-based screen identifies a XRE family regulator crucial for candicidin biosynthesis in Streptomyces albus J1074

正Dear Editor,Polyene macrolides are a group of natural products with potent antifungal activity (Caffrey et al., 2016). Candicidin/FR-008, a potent broad-spectrum anti-fungal agent, is produced by several Streptomycetes, including Streptomycetes sp. strain FR-008 (Chen et al., 2003), S. griseus 3570(Campelo and Gil, 2002) and S. albus J1074 (Olano et al.,2014). Due to its medical importance, considerable effort has been applied to elucidate its biosynthetic pathway and identify key regulatory genes (Chen et al., 2003; Zhang et al.,2015).     

Efficacy of chlorfenapyr against adult Tribolium castaneum exposed on concrete: effects of exposure interval, concentration and the presence of a food source after exposure

Chlorfenapyr, an insecticidal pyrrole, was applied to concrete arenas at concentrations of 1.1, 0.825, 0.55, and 0.275 g of active ingredient [AI]/m². Adult Tribolium castaneum (Herbst), the red flour beetle, were exposed for 2, 4, or 8 h at each concentration, then removed and held either with or without food (wheat flour) for 7 days. Survival was assessed when the beetles were removed from the exposure arenas and daily during the post-exposure period. In the presence of food, survival was high regardless of concentration and the day on which post-treatment survival was assessed, but survival did decrease as the exposure period increased from 4 to 8 h. When the beetles were not given food after exposure, survival at each concentration and exposure period declined during the 1-week post-exposure assessments. This pattern of decrease could be described by linear and non-linear equations. Results show the presence of food material greatly compromised effectiveness of the insecticide, and emphasize the importance of cleaning and sanitation in conjunction with insecticide treatments.     

Expression of the Tribolium castaneum （Coleoptera： Tenebrionidae） hsp83 gene and its relation to oogenesis during ovarian maturation

Heat shock proteins (HSP) can protect organisms and cells from thermal damage. In this study, we cloned the full length cDNA encoding the HSP83 protein (the homologue of HSP90) of Tribolium castaneum (red flour beetle). The isolated cDNA contains the full coding sequence, a partial 5′ untranslated region of 55 bp and the complete 3′ untranslated region. We found the hsp83 gene is located on chromosome 5 of the T. castaneum genome. The predicted HSP83 protein sequence has a high similarity (on average 86.77%) with that of other insect species. The expression of the hsp83 gene in the whole body and in the ovary could be induced with heat stress (40°C for 1 h) in newly hatched (within 3 h post emergence) and mature (10 days post emergence) beetles. Under normal conditions, the hsp83 expression in the ovary is about 3-fold higher than in the whole body at both stages. No significant difference in hsp83 expression was observed between the two ovarian developmental stages regardless if the beetles were treated with heat shock or not. The expression of the HSP83 protein in the whole body could also be induced with heat stress in newly hatched and mature beetles. However, in the ovary, HSP83 was only expressed in the follicle cells of mature beetles and not in newly hatched beetles, regardless if the beetles were treated with heat shock or not. Furthermore, the females were not able to produce mature oocytes after knock-down of the hsp83 expression by injecting dsRNA. These results suggest that the HSP83 protein is involved in protection against heat stress and could be involved in oogenesis during ovarian maturation of T. castaneum.     

Relationship between population growth of the red flour beetle Tribolium castaneum and protein and carbohydrate content in flour and starch

The effects of eight diets (atta flour, wheat flour, self-rising flour, rice flour, custard powder, corn flour, tapioca starch, and potato starch) on the development of the red flour beetle, Tribolium castaneum (Herbst), reared at 29-31 degrees C and 66-70% RH were assessed. Five pairs of male and female T. castaneum were reared on the respective diets for 28 d before the experimental setup was dismantled and adult counts were recorded. In another experiment, the insects were allowed to mate and oviposit in each flour or starch type over a period of 7 d before being removed. The counting of pupae and adult emergence began on the day of emergence and was continued on a daily basis until day 140. Proximate analysis was performed for chemical composition of each diet, and the numbers of new adults that developed were found to be positively correlated (r2 = 0.97; P < 0.05) with the protein content and negatively correlated (r2 = 0.93; P < 0.05) with the carbohydrate content. For T. castaneum, the suitable diets were ranked as follows: atta flour > wheat flour > self-rising flour > rice flour > custard powder > corn flour > tapioca starch > potato starch. T. castaneum larval development to the pupal and adult stages developed significantly faster in atta flour (P < 0.05) than in the other diets, and the greatest number of progeny was produced from beetles reared on atta flour. Fewer adults emerged from wheat flour, self-rising flour, and rice flour, and no new emergences were recorded for the remaining diets. Developmental rate was much slower in beetles reared on diets in which a low number in progeny was produced. These data illustrate that different diets can influence the sustainability of these insects and affect their development and growth.     

营养质量对雄性赤拟谷盗生长发育、抗饥饿和资源再获取能力的影响

昆虫的生长发育、抗饥饿和资源再获取能力对其生存、生殖和性选择非常重要。本文研究了营养质量对赤拟谷盗Tribolium castaneum(Herbst)生长发育、抗饥饿和资源再获取能力的影响。结果表明,三个营养处理下雄性赤拟谷盗的生长发育性状（幼虫重、发育历期、蛹重和成虫重）均存在显著性差异,在高营养质量下生长的雄性赤拟谷盗发育更快,体重更大,且各生长发育性状间存在显著性相关。营养质量对雄性赤拟谷盗成虫的抗饥饿能力没有显著影响,但对其资源再获取能力有显著影响,表现为在高营养质量下生长的雄性赤拟谷盗成虫比在低营养质量下生长的具有更高的资源再获取能力。雄性赤拟谷盗抗饥饿能力和资源再获取能力之间存在显著性相关,但是雄性赤拟谷盗抗饥饿能力和资源再获取能力除了与发育历期存在显著性相关外,与其它生长发育性状不存在显著性相关。本文还对这些实验结果的性选择意义进行了讨论。     

The stimulation of immune defence accelerates development in the red flour beetle (Tribolium castaneum)

The timing of the transition between life stages is of key importance for an organism. Depending on the environmental conditions, maturing earlier at a smaller size or maturing later at a larger size can be advantageous for fitness. Exposure to parasites and subsequent immune activation may lead to alterations in development. Immune defence often comes at a cost, such as energy drain towards immune function, which is likely to delay development. On the other hand, animals may react to an anticipated risk of infection with a phenotypically plastic shift in life history, which may more likely lead to accelerated development and earlier maturation. We tested these alternatives in the red flour beetle, Tribolium castaneum. Young larvae were exposed to a non-infectious immune challenge with heat-killed bacteria (either Escherichia coli or Bacillus thuringiensis) and they were followed up for their development, survival, adult size and reproduction. We found that animals that had experienced a bacterial challenge developed into adults earlier than sham-treated beetles, while they did not differ significantly in survival or adult size. Beetles exposed to E. coli produced fewer offspring, while exposure to B. thuringiensis did not affect offspring number. Taken together, our results indicate that T. castaneum is able to speed up its development when facing a risk of infection.     

The performance of processed mango (Mangifera indica) kernel flour in a model food system

Fresh mango (Mangifera indica) kernel was processed by soaking, sulphiting, blanching, drying and grinding into a powder, as processed mango kernel flour (PMKF), which could be substituted for wheat flour (WF) in biscuits. PMKF was incorporated into four grades of biscuits containing 50–100% PMKF (flour replacement basis). Results showed that the PMKF had lower contents (g kg⁻¹) of moisture (91), protein (66), higher fat (94), fibre (28) and ash (11) than WF used. The total carbohydrate contents of PMKF and WF were similar (710 g kg⁻¹) with starch constituting 500 g kg⁻¹. The 50:50 biscuit grade was preferred by panelists for colour, texture, flavour and overall acceptability. Other grades were favored only for the brown coloration, probably due to the contribution of the residual tannin in PMKF. The preferred biscuit had optimum protein supplementation and an increased 6.5% energy content compared with whole-wheat biscuit. These findings could encourage commercial manufacture of PMKF – WF blend biscuits where mango is abundant.     

Effect of five diatomaceous earth formulations against Tribofium castaneum （Coleoptera： Tenebrionidae）, Oryzaephflus surinamensis （Coleoptera： Silvanidae） and Rhyzopertha dominica （Coleoptera： Bostrychidae）

Laboratory bioassays were conducted to determine the effect of food source on the survival of Tribolium castaneum Herbst, Oryzaephilus surinamensis L. and Rhyzopertha dominica F., after exposure to five diatomaceous earth （DE） formulations： Protect-It, Insecto, Perma-GuardTM, Dryacide and SilicoSec. Adults of these species were exposed to DEs at the rate of 0.5 mg/cm^2 for 1 day on filter paper inside plastic Petri dishes. After exposure, the initial mortality was counted and live individuals of the three species were held for a week in glass vials containing 50 mg wheat flour, rice and whole wheat, respectively. In the second experiment, after 1 day exposure to DEs, beetles were transferred to Petri dishes without food and held for a week to determine if the presence of food source would decrease the mortality of beetles. Experiments were carried out at 27℃ and 55% RH in the dark. The initial mortality in both of the experiments reached 100% for the three species exposed to Protect-It and in the case ofR. dominica and O. surinamensis exposed to Dryacide. In contrast, low level of mortality （〈 10%） was observed for T. castaneum exposed to Perma-GuardTM and Insecto. The mortality after the post-treatment period on food was decreased for the three species exposed to Perma-GuardTM and in the case of T. castaneum and R. dominica exposed to Insecto and SilicoSec. Adults of O. surinamensis were the most susceptible followed by R. dominica and 100% adult mortality was obtained, whereas T. castaneum were the least susceptible beetles to DEs. Protect-It and Dryacide were the most efficient DE formulations and can be used effectively in a stored grain integrated pest management program.     

温度对赤拟谷盗爬行和起飞活动的影响

在不同温度下研究了赤拟谷盗Tribolium castaneum(Herbst)在固体物面、设定粮面、温度均匀的粮(小麦)柱和具有温度梯度粮柱内爬行扩散速度、起飞温度等.主要结果为:赤拟谷盗在17℃开始有爬行为,25℃开始有飞行行为,在15～25℃时水平爬行速度和15 ～ 20℃时竖直运动速度与温度呈显著正相关,在无障...     

Identification of microsatellite markers in the red flour beetle,Tribolium castaneum

We isolated and characterized microsatellite markers for the red flour beetle Tribolium castaneum, an important model species for studies in various areas of evolutionary biology and ecology. A microsatellite‐enriched genomic library was constructed and screened with single stranded oligonucleotide probes [(CCT)₁₇, (AAT)₁₇ and (CAG)₁₇]. Forty‐five primer pairs were designed of which 19 pairs produced successful amplification. Polymorphism screening involved beetles from five beetle strains and revealed 15 polymorphic and four monomorphic markers. The development of polymorphic microsatellite markers will facilitate future ecological and genetic studies involving T. castaneum beetles.     

Mortality and testicular derangements in red flour beetles, Tribolium castaneum (Herbst) exposed to hen's egg white proteins

Red flour beetle (T. castaneum) is a major pest of stored grains and is known for its adaptability to all classes of insecticides. The present study was carried out to determine the insecticidal potential of egg white proteins to manage beetle population. Protein samples obtained through salt fractionation were lyophilized and were used separately and simultaneously in different concentrations by adding them to wheat flour and milk powder. The results indicated that the mortality rate of the adult beetles was dependent on the type of treatment, concentration of protein samples and duration of feeding. In multiple-choice feeding trials beetles showed their movement towards the control section as the concentration of treatment increases. Marked abnormalities were observed in appearance and dimensions of the testes which indicated that the egg white proteins caused considerable effect on the process of spermatogenesis and sperm functions. SEM study revealed the formation of deep wrinkles and folds on the testicular surface of the testes of beetles fed on treated diets, points towards the depletion of internal cellular material. The results suggest that egg white protein affects the survival and cause subsequent derangements in the testis of red flour beetle.