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991.
992.
A. Lo Giudice P. Casella C. Caruso S. Mangano V. Bruni M. De Domenico L. Michaud 《Polar Biology》2010,33(7):929-943
A total of 253 hydrocarbon-oxidizing bacterial isolates were achieved from eight Antarctic surface seawater samples enriched
on diesel oil at 4°C. Isolates were screened by amplified ribosomal DNA restriction analysis prior to 16S rRNA gene sequencing.
Sequences were compared to those in available databases using the Basic Local Alignment Search Tool network service to determine
their approximate phylogenetic affiliations. The majority of the isolates were affiliated to the Actinobacteria (75.9%) and
the Gamma-Proteobacteria (22.9%). The Alpha- and Beta-Proteobacteria represented 0.8 and 0.4% of total isolates, respectively.
The Actinobacteria were predominantly allocated to the genera Arthrobacter, Cryobacterium and Rhodococcus. The Gamma-Proteobacteria were mainly found to be related to the genus Pseudomonas. Conversely, the Alpha- and Beta-Proteobacterial isolates shared the highest degree of sequence identity with unclassified
bacteria. Differences in the distribution of the detected phylotypes were observed among the analyzed samples. Isolates representing
each phylotype were selected for further characterization, including phenotypic assays and screening for the growth ability
in the presence of individual hydrocarburic substrates as the sole supplied carbon and energy source. Isolates possessed different
patterns of substrate utilization. Aliphatic hydrocarbons supported the growth of a higher number of isolates than aromatics.
Results confirm the ability of our Antarctic marine bacteria to utilize hydrocarbons at low temperature and therefore suggesting
that isolates with different substrate specificities can act in nature as a consortium in the utilization of complex hydrocarburic
mixtures. 相似文献
993.
Domenico L. Palenzona Annamaria Zattoni 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1970,40(8):345-346
Summary Artificial selection for wing length in Drosophila melanogaster resulted in changed crossing-over frequencies between three marker genes on the 2nd chromosome, b, cn and vg.The results suggest that artificial selection is a causal agent in producing the observed changes; moreover it is suggested that the modifications in cross-over frequency are controlled by extra-nuclear factors.Research supported by C.N.R. Consiglio Nazionale delle Ricerche Roma, Grant n. 115.2298.4791. 相似文献
994.
995.
The brown dog tick, Rhipicephalus sanguineus, is the most widespread tick in the world and infests primarily domestic dogs. Studies on the bio-ecology of R. sanguineus have been carried out worldwide, but little is known of the on-dog relationships of tick developmental stages and their possible
role on tick feeding performance, reproduction and pathogen transmission. We studied the relationships between different developmental
stages of R. sanguineus on particular body areas of naturally infested dogs. In addition, we assessed whether these relationships could vary according
to sex and breed of the dogs. Over 2,200 tick records were analyzed and the results showed that attachment sites of males
and females are strongly positively correlated whereas attachment sites of nymphs and adults tend to be negatively correlated.
Our findings indicate that adult ticks generally feed on sites (e.g., ears) that make it difficult for dogs to remove them,
whereas immatures feed on lower areas of the dog’s body (e.g., belly, rump, and hind legs), probably because of their more
limited mobility. Further research on the possible on-dog interactions of adult and immature ticks is needed to better understand
why their attachment sites tend to be negatively correlated and to assess their possible implications for pathogen transmission. 相似文献
996.
Teyssier C Grondin C Bonhomme L Lomenech AM Vallance M Morabito D Label P Lelu-Walter MA 《Physiologia plantarum》2011,141(2):152-165
An integrated physiological and proteomic approach was used to investigate the effects of high gellan gum concentration in the medium during maturation of somatic embryos (SE) of hybrid larch, by comparing embryos incubated in media with a high gellan gum concentration (8 g l(-1) ) and the standard concentration (4 g l(-1) ) after 1, 3, 6 and 8 weeks of maturation. Because of the reduced availability of water in the 8 g l(-1) medium, the cultured embryos had a lower osmotic water potential (Ψπ) and water contents, but higher dry weights (DWs), at 8 weeks compared with embryos cultured on the standard medium. The high gellan gum concentration induced a desiccation that is characteristic in zygotic embryo maturation. Total soluble proteins were extracted from SE with trichloroacetic acid (TCA)-acetone after 1 and 8 weeks of maturation on media with 4 and 8 g l(-1) of gellan gum, and separated by two-dimensional gel electrophoresis (2-DE) at pH 4-7. More than 1100 proteins were reproducibly detected on each gel. At 1 and 8 weeks respectively, the abundances of 62 and 49 spots detected in analyses of embryos matured at the two gellan gum concentrations, significantly differed. Among 62 significantly differing spots at 1 week of maturation, the corresponding proteins of 56 were reliably identified by liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS), and were found to be mainly involved in 'carbohydrate metabolism', 'genetic information processing' or 'environmental information processing' according to kegg taxonomy. Both physiological parameters and the proteins identified suggested that the embryos were stressed when they were cultured on 4 g l(-1) of gellan gum. 相似文献
997.
Albertin G Guidolin D Sorato E Oselladore B Tortorella C Ribatti D 《Regulatory peptides》2011,172(1-3):16-22
Urotensin-II (U-II) is an endogenous peptide recently characterized as a "nonclassic" pro-angiogenic cytokine. In fact, human vascular endothelial cells express the U-II receptor and exhibit a strong in vitro angiogenic response to the peptide, which was specifically triggered by the binding of U-II to its receptor and involved the activation of ERK1/2 and PI3K/Akt signaling pathways. Moreover, available studies, designed to investigate the pro-angiogenic effect quite shortly following U-II stimulation, suggested that the angiogenic action of the peptide was direct and not associated with an increased expression of vascular endothelial growth factor (VEGF) and/or its receptors. In the present study, the expression of three pro-angiogenic factors, namely VEGF, endothelin-1, and adrenomedullin, was studied in human umbilical vein endothelial cells (HUVEC) for longer times of U-II stimulation. RT-PCR and Western blot indicated that in HUVEC, exposed for at least 24h to U-II, the expression of the three angiogenic molecules was significantly increased at both mRNA and protein level, opening the possibility that U-II, not only could exert a direct stimulation of an angiogenic phenotype in endothelial cells quite shortly following exposure to the peptide, but could also further enhance the process indirectly by inducing in the cells a delayed production of other pro-angiogenic factors. Interestingly, a preliminary analysis of the time course of the in vitro capillary-like pattern formation was consistent with this view, suggesting a two phase temporal dynamics of the process. 相似文献
998.
Adrenal gland function is mediated through secreted hormones, which play a vital role in the autonomic and hypothalamic-pituitary-adrenal (HPA)-axis-mediated stress response. The genetic underpinnings of the stress response can be approached using a quantitative trait locus (QTL) analysis. This method has been used to investigate genomic regions associated with variation in complex phenotypes, but it has not been used to explore the structure of the adrenal. We used QTL analyses to identify candidate genes underlying adrenal weight and adrenal cortical zone and medulla widths. We used 64 BXD recombinant inbred (RI) strains of mice (n?=?528) and 2 parental strains (C57BL/6J and DBA/2J; n?=?20) to measure adrenal weights and adrenal zone widths. For adrenal weight, we found significant QTLs on chromosome 3 for females (Fawq1) and Chr 4 for males (Mawq1) and suggestive QTLs on Chrs 1, 3, 10, and 14 for females and Chrs 2, 4, 10, 17, and X for males. We identified a significant QTL on Chr 10 (Mawdq1) and a suggestive QTL on Chr 13 for male adrenal total width. For male adrenal medulla width, we found a significant QTL on Chr 5 (Mmwdq1) and a suggestive QTL on Chr 1. We also identified significant QTLs on Chrs 10 (Mxwdq1) and 14 (Mxwdq2) for male X-zone width. There are 113 genes that mapped within the significant QTL intervals, and we identified 4 candidate genes associated with adrenal structure and/or function. In summary, this study is an important first step for detecting genetic factors influencing the structure of the adrenal component of the HPA axis using QTL analyses, which may relate to adrenal function and provide further insights into elucidating genes critical for stress-related phenotypes. 相似文献
999.
De Domenico S Bonsegna S Lenucci MS Poltronieri P Di Sansebastiano GP Santino A 《植物学报(英文版)》2011,53(11):858-868
Oleosin, caleosin and steroleosin are normally expressed in developing seed cells and are targeted to oil bodies. In the present work, the cDNA of each gene tagged with fluorescent proteins was transiently expressed into tobacco protoplasts and the fluorescent patterns observed by confocal laser scanning microscopy. Our results indicated clear differences in the endocellular localization of the three proteins. Oleosin and caleosin both share a common structure consisting of a central hydrophobic domain flanked by two hydrophilic domains and were correctly targeted to lipid droplets (LD), whereas steroleosin, characterized by an N-terminal oil body anchoring domain, was mainly retained in the endoplasmic reticulum (ER). Protoplast fractionation on sucrose gradients indicated that both oleosin and caleosin-green fluorescent protein (GFP) peaked at different fractions than where steroleosin-GFP or the ER marker binding immunoglobulin protein (BiP), were recovered. Chemical analysis confirmed the presence of triacylglycerols in one of the fractions where oleosin-GFP was recovered. Finally, only oleosin- and caleosin-GFP were able to reconstitute artificial oil bodies in the presence of triacylglycerols and phospholipids. Taken together, our results pointed out for the first time that leaf LDs can be separated by the ER and both oleosin or caleosin are selectively targeted due to the existence of selective mechanisms controlling protein association with these organelles. 相似文献
1000.
Vicari E La Vignera S Arcoria D Condorelli R Vicari LO Castiglione R Mangiameli A Calogero AE 《PloS one》2011,6(4):e18647