Cloning of a novel murine gene Sfmbt, Scm-related gene containing four mbt domains, structurally belonging to the Polycomb group of genes

We cloned six cDNAs by screening cDNA libraries of cypris larvae from barnacles, Balanus amphitrite, and studied their expression by Northern blot analysis. All of them are expressed in the cypris larvae at the settlement stage, but not in the earlier nauplii larvae nor in later adult barnacles. Therefore, we designated them as barnacle cypris larva-specific genes (bcs); bcs-1, bcs-2, bcs-3, bcs-4, bcs-5 and bcs-6. During the process of larval attachment and metamorphosis, the amounts of bcs-1 and bcs-2 mRNAs decreased, whereas the bcs-3, bcs-4, bcs-5 and bcs-6 mRNAs increased. A homology search showed that all cDNAs encode novel peptides containing characteristic amino acid sequences. This study strongly suggests that these bcs gene products are involved in the cypris larval attachment and metamorphosis of barnacles.     

Phenotypic variation for adhesive tenacity in the barnacle Balanus amphitrite

Silicone fouling-release coatings represent a non-toxic alternative to biocide-containing ship hull paints. These coatings allow fouling organisms to attach to the hull surface, but prevent firm adhesion. Adhesive tenacity to fouling-release materials varies both among and within species. We quantified broad-sense genetic and environmental sources of intraspecific variation in tenacity to two silicone substrata, for the barnacle Balanus amphitrite. For both materials tenacity varied over an order of magnitude; however, the partitioning of this variation differed between the substrata. For International Veridian, a commercially-available fouling-release coating, removal stress varied significantly among maternal families and replicate barnacle cultures. Variation among the maternal families was associated with previously observed differences among these families in the condition of the adhesive plaque. Additional experiments suggested that variation among the replicate cultures arose from heterogeneity between replicate coatings in properties that affect tenacity. We could not attribute variation in removal stress for Dow Corning Silastic T-2, a silicone rubber used for mold-making, to any of the genetic or environmental sources tested. Instead, variation may have been due to measurement error or heterogeneity within replicate coatings in properties affecting tenacity. Differences among maternal families in removal stress may stem from variation in the interaction between the adhesive and the substratum, or in the viscoelastic properties of the adhesive plaque.     

Evolutionary relationships among aquatic anamorphs and teleomorphs: Lemonniera, Margaritispora, and Goniopila

The hypothesis that similar conidial morphologies in aquatic hyphomycetes are a result of convergent evolution was tested using molecular sequence data. Cladistic analyses were performed on partial sequences of 28S rDNA of seven species of Lemonniera, one species of Margaritispora and one species of Goniopila. Lemonniera has tetraradiate conidia with long arms, whereas Margaritispora and Goniopila have typically globose (isodiametric) conidia, with short conical protuberances in a stellate or quadrangular arrangement. Lemonniera and Margaritispora have phialidic conidiogenesis and both produce dark, minute sclerotia in culture whereas Goniopila has holoblastic conidiogenesis and does not produce sclerotia in culture. Goniopila produces a microconidial phialidic synanamorph in culture. All three genera have schizolytic conidial secession. Molecular analyses demonstrate that Lemonniera species are placed in two distinct clades: one within Leotiomycetes; the other within Pleosporales, Dothideomycetes. Margaritispora is placed with Lemonniera species within Leotiomycetes. Goniopila and Lemonniera pseudofloscula are placed within Dothideomycetes. No morphological character was entirely congruent with the molecular derived phylogeny. This suggests that for the group of species studied, conidial shape is not a reliable indicator of phylogeny but more likely the result of convergent evolution in response to the aquatic environment.     

A new fungal genus, Teracosphaeria, with a phialophora-like anamorph (Sordariomycetes, Ascomycota)

The new genus and species Teracosphaeria petroica is described for a perithecial ascomycete and its anamorph occurring on decayed wood collected in New Zealand. The fungus produces immersed, non-stromatic ceratosphaeria-like perithecia in nature, with hyaline, septate ascospores produced in unitunicate, non-amyloid asci. The anamorph produced in vitro is phialophora-like with lightly pigmented phialides terminating in flaring, deep collarettes that are often noticeably brown with conspicuous periclinal thickening. Phylogenetic analysis of LSU rDNA sequence data indicates that this fungus is distinct from morphologically similar fungi classified in the Chaetosphaeriales, the Trichosphaeriales or the Magnaporthaceae. It forms a monophyletic group with recently described, chaetosphaeria-like ascomycetes, such as the pyrenomycete genus Mirannulata, and shows affinity with the anamorphic species Dictyochaeta cylindrospora. The usefulness of describing anamorph genera for morphologically reduced anamorphs, when anamorph characteristics are actually part of the holomorph diagnosis, is discussed. An apparently contradictory example of the so-called Cordana and Pseudobotrytis anamorphs of Porosphaerella spp. is also discussed.     

Taxonomy, molecular phylogeny, and ultrastructural morphology of Olpidiopsis porphyrae sp. nov. (Oomycetes, straminipiles), a unicellular obligate endoparasite of Bangia and Porphyra spp. (Bangiales, Rhodophyta)

Olpidiopsis porphyrae sp. nov., a marine oomycete endoparasite that infects the commercially cultivated red alga Porphyra yezoensis, is described and its phylogenetic position based on molecular data and ultrastructural morphology is discussed. O. porphyrae infects the host Porphyra by means of encysted zoospores. Spherical-shaped holocarpic thalli develop within the cytoplasm of its algal host, which produce monoplanetic, subapically biflagellate zoospores. The characteristic features of this isolate are the ellipsoidal, unicellular thallus and simple holocarpic zoosporangial development, which show morphological similarity with the genus Olpidiopsis. Laboratory infection experiments with a wide range of green, brown, and red algae revealed that O. porphyrae infects several stages of the bangialean red algae (the genera Bangia and Porphyra). Molecular phylogenetic analyses inferred from both SSU rRNA and cox2 genes showed O. porphyrae branched before the main saprolegnian and peronosporalean lineages within the monophyletic oomycete clade, indicating its phylogenetic separation from them. A single or double K-body-like organelle, which contains tubular inclusions, is found located to one side of the zoospore nucleus and shows similarities to homologous organelles previously described in O. saprolegniae. The ultrastructural morphology of O. porphyrae with zoospore initials containing K-bodies and tubular mitochondrial cristae is characteristic of oomycetes. Group I intron-like multiple insertions were found in the SSU rRNA gene of O. porphyrae. This is the first report of SSU group I introns in the class Oomycetes.     

金龟子绿僵菌对斜纹夜蛾幼虫的生防效果、抗氧化酶活性和肠道细菌群落的影响

【目的】测定金龟子绿僵菌(Metarhizium anisopliae)对斜纹夜蛾(Spodoptera litura) 2龄幼虫的毒力,研究金龟子绿僵菌侵染后寄主体内抗氧化酶活性和肠道内细菌群落的变化,探讨斜纹夜蛾对金龟子绿僵菌侵染的防御机制。【方法】采用浸渍法测定不同浓度金龟子绿僵菌对斜纹夜蛾2龄幼虫的毒力;应用IlluminaMiSeq高通量测序技术测定肠道细菌群落。【结果】不同浓度的孢悬液对斜纹夜蛾2龄幼虫均有一定的毒力,处理7 d时半致死浓度(LC₅₀)为3.944 107个孢子/mL;浓度为1.0×10⁹个孢子/mL时,半致死时间最短(LT₅₀)为4.6 d,校正后的死亡率为81.03%。处理后未致死的斜纹夜蛾幼虫体内抗氧化酶活性显著高于对照组。处理后致死的斜纹夜蛾幼虫肠道细菌群落多样性显著高于对照组;且处理后致死的斜纹夜蛾幼虫肠道细菌群落组成与对照组差异显著。【结论】金龟子绿僵菌对斜纹夜蛾幼虫的致死率和致死效率与金龟子绿僵菌的浓度呈正相关;斜纹夜蛾幼虫体内的抗氧化酶可能在抵抗金龟子绿僵菌侵染的过程中起重要作...     

Characterisation of cell wall polysaccharides, arabinogalactans-proteins (AGPs) and phenolics of Cola nitida, Cola acuminata and Garcinia kola seeds

Many Cola plant species are endemic to West and Central Africa. Cola acuminata and Cola nitida are used as masticatory when fresh, while the dried nuts are used for beverages and pharmaceutical purposes in Europe and North America. Garcinia kola seeds, that serve as a substitute for the true kola nuts, are used in African traditional medicine for the treatment of various diseases, including colic, headache and liver cirrhosis. Seeds extracts of G. kola are also known for their anti-inflammatory, antimicrobial and antiviral properties. To gain information on the chemical properties of the kolas, we have isolated and analyzed cell wall polysaccharides, arabinogalactan-proteins and phenolic substances from the seeds of the three kola species. The sugar composition of cell wall material of C. acuminata, C. nitida and G. kola revealed that Gal (up to 30%), Ara, GalA and Glc as the predominant monosaccharides, representing approximately 90% by mol of the total hydrolysable sugar present in this material. In Ammonium oxalate cell wall fraction, GalA was found to be the major sugar present in all kola species. In the alkali-soluble fraction, there were significant differences in the level of Glc and Gal. The level of Glc was high in C. acuminata and C. nitida while the level of Gal and Xyl were high in C. nitida and G. cola. Isolation and quantification of arabinogalactan-proteins demonstrate that G. kola seeds contained four to eight times more of these proteoglycans than the seeds of the other two species. Finally, analysis of soluble phenolic substances shows that caffeine and catechin were largely represented in C. acumina and C. nitida seeds, with caffeine accounting for 50% of all soluble phenolics. These findings indicate that the three Kola seeds are highly enriched in pectins and proteoglycans and that C. acuminata and C. nitida can be used as a possible source of caffeine and catechin.     

意大利蜜蜂工蜂幼虫nkd基因的生物信息学分析及功能研究

【目的】意大利蜜蜂(Apis mellifera ligustica,简称意蜂)是西方蜜蜂(Apis mellifera)的亚种之一。蜜蜂球囊菌(Ascosphaera apis)侵染意蜂幼虫导致白垩病。本研究对西方蜜蜂裸表皮蛋白(naked cuticle, Nkd)进行保守基序预测和系统进化分析,并通过RNAi明确nkd基因对意蜂工蜂幼虫体重及宿主响应蜜蜂球囊菌胁迫的免疫应答的影响,以期丰富西方蜜蜂基因nkd的信息,并揭示意蜂幼虫nkd的功能。【方法】通过MEME软件预测西方蜜蜂和其他9个物种Nkd蛋白的保守基序。采用MEGA X软件对西方蜜蜂及其他9个物种的Nkd蛋白进行系统进化分析。通过饲喂dsRNA对意蜂幼虫肠道内的nkd进行RNAi。使用电子天平对幼虫进行称重。利用RT-qPCR检测nkd基因的干扰效率及免疫基因的相对表达量。【结果】西方蜜蜂与东方蜜蜂、柑橘凤蝶、家蚕和金凤蝶的Nkd蛋白均含有3个保守基序(motif 1、motif 2 和motif 3),说明上述5个昆虫物种的Nkd具有较高的保守性。西方蜜蜂与东方蜜蜂的Nkd蛋白聚为一支,说明二者的亲缘关系近。与dsRNA-egfp组相比,dsRNA-nkd组5日龄和6日龄幼虫肠道内nkd的表达量均极显著下调(P<0.001),干扰效率分别为49.60%和56.40%。另外,dsRNA-nkd组幼虫体重较dsRNA-egfp组显著下降,说明nkd显著影响幼虫体重。RT-qPCR结果显示,4日龄幼虫肠道内abaecin、apidaecin、birc5、defensin-1和PGRP-S2均被激活表达;5日龄幼虫肠道内abaecin、apidaecin、birc5和defensin-1均被激活表达,PGRP-S2的表达受到抑制;6日龄幼虫肠道内abaecin被激活表达,而apidaecin、birc5、defensin-1和PGRP-S2的表达均受到抑制,说明上述5个免疫基因在宿主响应胁迫的过程中呈不同的表达趋势,均参与宿主的免疫应答,nkd与abaecin和apidaecin的表达存在负向调控关系。【结论】西方蜜蜂的Nkd蛋白含有3个保守基序(motif 1、motif 2和motif 3),西方蜜蜂与东方蜜蜂的Nkd蛋白亲缘关系最近,通过饲喂dsRNA能有效干扰意蜂工蜂幼虫肠道内nkd表达,nkd影响意蜂工蜂幼虫体重及宿主对蜜蜂球囊菌胁迫的免疫应答。     

New species of Phaeoramularia, Pseudocercospora and Stenella from Western Ghats of India

Four new species of the hyphomycete genera Phaeoramularia viz. Ph. caesalpinae, Pseudocercospora viz., Ps. tiliacearum, Stenella, viz. S. argyreiae and S. grewiae occurring on Caesalpinia bonducella Fleming (Caesalpiniaceae), Grewia sp. (Tiliaceae), Argyrea sp. Lour (Convolvulaceae) and Grewia sp. L. (Tiliaceae), respectively are described and illustrated here. All these fungi were collected from Western Ghats of India.     

The phylogenetic placement of the Leucogastrales, including Mycolevis siccigleba (Cribbeaceae), in the Albatrellaceae using morphological and molecular data

The morphology of many hypogeous fungi converges on a homogeneous reduced form, suggesting that disparate lineages are subject to a uniform selection pressure. The primary goal of this study was to evaluate the morphology and infer the phylogeny of the Leucogastrales with Mycolevis siccigleba using a Bayesian methodology. A comprehensive morphological assessment was used for an a priori phylogenetic inference to guide the sequencing effort. All structures except spore ornamentation pointed to the Albatrellaceae as the most likely sister taxon. Polyporoletus sublividus, a close relative of Albatrellus, produces ornamented basidiospores with a similar structure to M. siccigleba basidiospores. The ITS from 30 taxa was used for the molecular phylogenetic analysis. P. sublividus was found sister to Mycolevis. Leucophleps spinispora and L. magnata formed a group sister to the Polyporoletus/Mycolevis group, whereas Leucogaster was polyphyletic with respect to the core of the Leucogastrales and sister to A. caeruleoporus. This relationship was expected as previously undescribed chlamydospores produced by members of Albatrellus had a similar morphology to the basidiospores of L. rubescens.     

长日照下IQM3在CO的下游调控拟南芥主根长度

拟南芥(Arabidopsis thaliana)中IQM家族是含有IQ基序的钙调素结合蛋白家族,IQM3突变能增加主根长度,CO (CONSTANS)是光周期成花调控途径的重要成员,CO突变可缩短主根长度。该研究构建二者的双突变体研究IQM3与CO基因的遗传学关系。结果表明,新CO突变体co-12序列的第1个外显子上缺失了9个碱基ACTTGCTAG,其中含有限制性核酸内切酶BfaI的酶切位点CTAG。建立了可鉴定该突变体的分子标记：利用BfaI酶切跨编码区PCR产物时,野生型Col因有3个位点而得到4个片段,co-12因只有2个位点而得3个片段,CO/co-12杂合子得5个片段。在长日照下,co-12的主根长度比野生型Col短,iqm3-2的比野生型Col长,而双突变体co-12 iqm3-2的主根长度表型偏向于iqm3-2。因此,在长日照下,IQM3在CO的下游参与调控拟南芥主根长度。     

Effect on prolactin secretion of Echinacea purpurea, Hypericum perforatum and Eleutherococcus senticosus

It has been recently reported that prolactin (PRL) plays an important role in immune system regulation. In this study we investigated the activity of three natural drugs with immunomodulatory activity: Echinacea purpurea (EP), Hypericum perforatum (HP) and Eleutherococcus senticosus (ES) on PRL production. Male rats were orally treated with two different doses (30 and 100 mg/kg) of extract of these drugs for 3 or 15 days. A 3-day treatment was not able to modify PRL serum levels, whereas a 15-day treatment with EP and HP at the higher dose significantly inhibits PRL production. A treatment with ES was always ineffective. A possible mechanism for this effect could be that both HP and EP extracts display a direct dopaminergic activity, although an involvement of the GABA-ergic system cannot be excluded.     

Development and dehiscence of the cephalothecoid peridium in Aporothielavia leptoderma shows it belongs in Chaetomidium

The development of the cephalothecoid peridium of Aporothielavia leptoderma was examined using light and electron microscopy. Early stages in ascoma initiation were consistent with previous reports for other species in the Chaetomiaceae. However, as young cleistothecia increased in size, clusters of peridial cells in the outer textura angularis elongated in a radial pattern around a central cell or cell cluster to form rosettes of relatively thick-walled segments that marked the central areas of incipient cephalothecoid plates. The external flank along median portions of the radial cells became thin walled and swelled outwards so that each plate became concave and was separated from adjacent plates by a more or less circular to polygonal ridge of knuckle-shaped swellings. When dry, mature peridia split apart along some of the ridges demarcating individual plates but an internal mechanism for liberating ascospores from the confines of the ascoma was not observed. Physical disturbance of mature cleistothecia by beetles, when enclosed together in a Petri dish, shattered the peridia, liberating the ascospores. Smaller insects were unable to cause disarticulation of the cephalothecoid plates. Because of the presence of an apical germ pore in the ascospores and morphological similarity to Chaetomidium arxii, the new combination Chaetomidium leptoderma (syn. Thielavia leptoderma) comb. nov. is proposed.     

荔枝、龙眼与其属间杂种的茎、叶解剖结构比较

为比较荔枝(Litchi)和龙眼(Dimocarpus)与其属间杂种的茎、叶解剖结构,采用徒手切片法、组织离析法和石蜡切片法对茎、叶片结构进行观察比较。结果表明,‘杂种A’和‘杂种B’的髓率、树皮率均居于父母本之间,而木质部率、导管总面积/木质部面积的比值、导管分子内径则表现出显著的超亲优势;‘杂种C’和‘杂种D’的树皮率和射线宽度均小于父母本。‘杂种A’和‘杂种B’导管分子无尾和两端水平的频率居于父母本之间,‘杂种C’和‘杂种D’的导管分子形态特征较接近其母本‘石峡’,‘杂种D’的导管分子长度显著大于父母本。4个杂种的叶主脉厚均居于父母本之间,‘杂种D’的叶脉突起度和‘紫娘喜’的栅栏组织/海绵组织厚度比值均显著大于其他试材。4个属间杂种叶片表皮细胞的大小、垂周壁的形态均居于父母本之间;荔枝和龙眼叶片表皮特征差异明显,可以作为两属的鉴别特征。4个属间杂种的解剖结构总体上呈现出较明显的偏母遗传效应。     

中华蜜蜂6日龄幼虫响应蜜蜂球囊菌胁迫的环状RNA应答

【目的】蜜蜂球囊菌(Ascosphaera apis,简称球囊菌)专性侵染蜜蜂幼虫而导致白垩病,危害蜜蜂健康和养蜂生产。本研究旨在探究中华蜜蜂(Apis cerana cerana,简称中蜂) 6日龄幼虫响应球囊菌胁迫的环状RNA(circular RNA,circRNA)差异表达谱及差异表达circRNA (differentially expressed circRNA,DEcircRNA)在宿主胁迫应答中的潜在功能。【方法】利用去除线性RNA的circRNA-seq技术对正常和球囊菌侵染的中蜂6日龄幼虫肠道(AcCK和AcT)进行测序。利用find_circ软件鉴定circRNA,统计circRNA的长度和环化类型。根据|log_2(Fold change)|≥1和P≤0.05的标准筛选DEcircRNA。将DEcircRNA的来源基因比对Gene ontology (GO)数据库和Kyoto Encyclopedia of Genes and Genomes (KEGG)数据库,从而获得功能及通路(pathway)注释。随机挑选3个DEcircRNA进行RT-qPCR验证。【结果】AcCK和AcT的circRNA-seq分别得到76342570和68269362条原始读段(raw reads),经严格质控得到74524108和66974392条有效读段(clean reads),Q30分别为92.75%和94%,GC含量分别为54.31%和54.90%。比对上东方蜜蜂(Apis cerana)参考基因组的短序列读段(anchor reads)共计23648400条。AcCK和AcT中分别鉴定到805和702个circRNA,长度均介于201–1000 nt,数量最多的环化类型均为已注释外显子circRNA,但分布在不同长度、不同环化类型的circRNA数量存在差异。AcCK vs AcT比较组共有494个DEcircRNA,包括257个上调circRNA和237个下调circRNA;上调和下调幅度最大的circRNA分别为novel_circ_000123和novel_circ_000726。上述DEcircRNA的来源基因可注释到11条生物学进程相关条目,9条分子功能相关条目,9条细胞组分相关条目,以及73条通路。进一步分析发现,部分DEcircRNA的来源基因注释到7条细胞免疫通路和3条体液免疫通路。【结论】中蜂6日龄幼虫响应球囊菌胁迫的过程中可能通过改变分布在不同长度和环化类型的circRNA数量,以及特异性表达一些circRNA和调节部分circRNA的表达量对病原产生应答;novel_circ_000027、novel_circ_000127、novel_circ_000312等DEcircRNA在宿主的胁迫应答过程中可能通过调控氧化磷酸化、细胞和体液免疫等通路发挥特殊作用。研究结果为深入理解中蜂幼虫对球囊菌的胁迫应答机制及二者的相互作用机制提供了新见解。     

Lipid and fatty acid composition of striped bass (Morone saxatilis) larvae during development

Changes in lipid class, fatty acid composition, protein, and dry and wet weights of fertilized eggs and developing larvae of striped bass (Morone saxatilis) fed with the live food, Artemia, were investigated. A decrease of wet and dry weights and moisture was observed at the beginning of the larval stage. Larvae regained the original moisture level, and wet and dry weights increased steadily after feeding. Total lipids decreased from 190 μg/egg in fertilized eggs to 151 μg/egg during hatching and increased after feeding. When total lipid contents were expressed as a percentage of larval dry weight, a decline of lipid did not occur until after feeding. Total protein, on the other hand, increased right after feeding, but there was some variation between days. Polar lipids increased significantly from 20 μg/egg at the egg stage to 199 μg/larva at 26 days post-hatching (DPH), 2 days before the onset of metamorphosis, while neutral lipids declined from 175 μg/egg to 80 μg/larva during the same time period. Wax/steryl esters decreased from 150 μg/egg in fertilized eggs to 32 μg/larva at 26 DPH. Triacylglycerols dropped from 21 μg/egg to 15 μg/larva before feeding and increased gradually after feeding. In contrast, the level of cholesterol increased 2–3-fold. There was a significant increase of phospholipids, particularly phosphatidylcholine in larvae after feeding. The fatty acid composition of fish larvae was significantly influenced by the diet, Artemia. There was an indication of catabolism of endogenous eicosapentaenoic and docosahexaenoic acids during metamorphosis.