Identification of miR414 and expression analysis of conserved miRNAs from Stevia rebaudiana

MicroRNAs (miRNAs) usually contain 19-24 nucleotides and have been identified as important eukaryotic gene regulators. Applications of various computational approaches have simplified the task by predicting miRNAs from available sequence data sources. In this study, we identified a conserved miR414 from a computational analysis of EST sequence data available from Stevia rebaudiana. In addition, we also identified six conserved miRNAs namely miR169, miR319, miR414, miR164, miR167 and miR398 using stem-loop RT-PCR analysis. Hence, miR414 was commonly identified using both methods. The expression analysis of these miRNAs documented their roles in growth and development of Stevia. Furthermore, the detected miRNAs were found to target genes involved in plant growth, development, metabolism and signal transduction. This is the first study reporting these conserved miRNAs and their expression in Stevia.     

Cloning and expression analysis of a water stress-induced gene from Brassica oleracea.

Plant growth and productivity are greatly affected by water stress, such as drought and salinity. Here we report on the cloning and expression analysis of a water stress-induced gene from Brassica oleracea (designated as BoWS, GenBank accession number AY571333) by rapid amplification of cDNA ends (RACE). The full-length cDNA of BoWS consisted of 594 bp and contained a 285 bp open reading frame (ORF) encoding a 95-amino-acid protein. The deduced protein had a calculated molecular mass of 10.53 kDa and an isoelectric point of 6.93. The sequence similarity and comparative analysis showed that BoWS was 84% identical to Arabidopsis thaliana putative water stress-induced protein (GenBank accession number AAM67282). Southern blot analysis indicated that BoWS was a low-copy gene. Northern blot analysis revealed that the expression of BoWS was upregulated by abscisic acid (ABA), mannitol, NaCl, drought, salicylic acid (SA) and hydrogen peroxide (H(2)O(2)). Our results indicate that BoWS is extremely related to the water-deficit stress in B. oleracea.     

大白菜一个冷相关基因的分离与逆境诱导表达(英文)

以冷处理的大白菜幼叶为材料,采用RT-PCR技术获得1条新的冷相关基因序列(BpCOR,GenBank登录号DQ491005)。该基因编码129个氨基酸的亲水多肽,预测其N端含有叶绿体转运肽序列。多序列比对显示,Bc-COR蛋白与拟南芥及其它植物COR具有较高的相似性。Northern杂交结果显示BcCOR基因能被冷处理强烈诱导表达,而被脱水和盐处理弱诱导;在冷处理下,BcCORmRNA在根中的积累量低于叶片,光照能显著加强该基因在叶片中的表达。研究表明,BcCOR基因可能在大白菜抵抗冷胁迫和其它非生物胁迫的过程中具有重要的作用。     

Isolation and characterization of a homologous to lipase gene from Brassica napus

Lipase is an important lipolytic enzyme involved in plant lipid metabolism. To analyze its function and roles during seed germination and growth, a full-length cDNA encoding a homologous to lipase gene named BnLIP1 was cloned from Brassica napus, cv. Huyou 15, by rapid amplification of cDNA ends. The BnLIP1 gene had a total length of 1318 bp, with an open reading frame of 1170 bp encoding 389 amino acid residues. Sequence analysis revealed that BnLIP1 protein belonged to the GDSL family of serine esterases/lipases. In B. napus genome, BnLIP1 is represented by several copies with the length of 1601 bp, the gene comprises five exons and four introns. RT-PCR analysis indicated that BnLIP1 showed no tissue-specific expression during reproductive growth and is strongly expressed during seed germination. No expression could be detected until three days after germination, and its peak was registered at the fifth day after germination. In conclusion, BnLIP1-encoded protein is predicted to be a lipolytic enzyme widely expressed at various stages of oilseed rape germination and development. Published in Russian in Fiziologiya Rastenii, 2006, Vol. 53, No. 3, pp. 410–417. The text was submitted by the authors in English.     

Cloning and expression analysis of a CMS-related gene BcCoi1 from Brassica campestris ssp. chinensis

BcCoi1, a cytoplasmic male sterility related gene, which was isolated from flower buds of Brassica campestris ssp. chinensis Makino using the RACE technology, was characterized and submitted to the NCBI GenBank (accession no. GU263836). The gene encodes a 67.78-kD protein containing 16 leucine-rich repeats and an N-terminal F-box motif and is extremely similar to Arabidopsis thaliana Coi1 gene. The Southern blot showed that BcCoi1 belongs to a multigene family. In A. thaliana, the Coi1 gene is involved in jasmonate signaling, and Coi1 mutant displayed male sterility. In this study, qPCR results demonstrated that BcCoi1 was accumulated in stamens and was significantly higher expressed in flower organs of the maintainer line than in the CMS one. At the microsporocyte development stage, the gene was expressed at a significantly lower extent in the CMS line than in the maintainer line. This expression profile presumes that BcCoi1 plays a role in early microspore development in non-heading Chinese cabbage.     

八门湾红树林土壤芽胞杆菌分离与多样性分析

【目的】了解八门湾红树林海漆林区土壤中可培养芽胞杆菌资源的多样性。【方法】采用水浴处理与直接涂布相结合的方法选择性分离土壤中的芽胞杆菌;利用16S rDNA PCR-RFLP与16S rDNA序列分析技术研究可培养芽胞杆菌资源的遗传多样性和系统发育关系。【结果】16S rDNA PCR-RFLP酶切图谱UPGMA聚类分析表明,在100%的相似性水平上,分离的155株芽胞杆菌分属21个遗传类群,显示了较为丰富的遗传多样性;由21种遗传类型代表菌株的16S rDNA序列分析结果得知,这些芽胞杆菌主要分布在Bacillaceae和Paenibacillaceae科下的Bacillus、Halobacillus、Virgibacillus和Paenibacillus 4个属,其中Bacillus为优势属;有8株芽胞杆菌的16S rDNA序列与数据库中相应模式菌株的最大相似性在95.1%-99.0%之间。【结论】八门湾红树林土壤可培养芽胞杆菌有着较为丰富的遗传多样性,并存在新的芽胞杆菌物种资源。     

Isolation and functional analysis of a Brassica juncea gene encoding a com-ponent of auxin efflux carrier

Polar auxin transport plays a divergent role in plant growth and developmental processes including root and embryo development, vascular pattern formation and cell elongation. Recently isolated Arabidopsis pin gene family was believed to encode a component of auxin efflux carrier (G(?)lweiler et al, 1998). Based on the Arabidopsis pin1 sequence we have isolated a Brassica juncea cDNA (designated Bjpin1), which encoded a 70-kDa putative auxin efflux carrier. Deduced BjPIN1 shared 65% identities at protein level with AtPINl and was highly homologous to other putative PIN proteins of Arabidopsis (with highest homology to AtPIN3). Hydrophobic analysis showed similar structures between BjPINl and AtPIN proteins. Presence of 6 exons (varying in size between 65 bp and 1229 bp) and 5 introns (sizes between 89 bp and 463 bp) in the genomic fragment was revealed by comparing the genomic and cDNA sequences. Northern blot analysis indicated that Bjpin1 was expressed in most of the tissues tested, with a relatively h     

Isolation of a newLegionella species from thermally altered waters

Legionella-like bacteria were isolated from thermally altered water in Pennsylvania and Minnesota. These organisms were isolated from tissues of infected guinea pigs after intraperitoneal inoculation of water concentrates. While the cultural and morphological characteristics indicated the isolates wereLegionella, they did not react with antibodies prepared against known species of the genus. Antisera prepared against one of the isolates reacted maximally with the other ten isolates. Fluorescent antibody analysis of water concentrates from geographically disparate sites indicated that the environmental distribution is broad and that concentrations of the Oak Ridge strain ofLegionella were similar to those of serogroups 1, 2, 3, and 4 ofLegionella pneumophila.