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121.
Michael Stöcker Garcia-Mas Jordi Pere Arús Ramon Messeguer Pere Puigdomènech 《Plant molecular biology》1993,22(5):913-916
The sequence of an -tubulin from Prunus amygdalus has been obtained by cDNA cloning. When this sequence is compared to that of the Tub1 gene from maize it shows a very high degree of similarity, much higher than any of the -tubulin sequences reported so far from plants. The expression of this gene is high in the stages of seed development where a high divisional activity is present. It is preferentially expressed in the radicular tissues as it is gene Tub1 in maize. Southern analysis indicates that this gene may from a subfamily of -tubulin genes having similar sequence and tissue specificity and existing at least in maize and in Prunus. 相似文献
122.
Leire Aguinagalde Bruno Corsini Arnau Domenech Mirian Domenech Jordi Cámara Carmen Ardanuy Ernesto García Josefina Li?ares Asunción Fenoll Jose Yuste 《PloS one》2015,10(9)
Capsular switching allows pre-existing clones of Streptococcus pneumoniae expressing vaccine serotypes to escape the vaccine-induced immunity by acquisition of capsular genes from pneumococci of a non-vaccine serotype. Here, we have analysed the clonal composition of 492 clinical isolates of serotype 11A causing invasive disease in Spain (2000–2012), and their ability to evade the host immune response. Antibiograms, serotyping and molecular typing were performed. The restriction profiles of pbp2x, pbp1a and pbp2b genes were also analysed. Interaction with the complement components C1q, C3b, C4BP, and factor H was explored whereas opsonophagocytosis assays were performed using a human cell line differentiated to neutrophils. Biofilm formation and the polymorphisms of the major autolysin LytA were evaluated. The main genotypes of the 11A pneumococci were: ST62 (447 isolates, 90.6%), followed by ST6521 (35 isolates, 7.3%) and ST838 (10 isolates, 2.1%). Beta lactam resistant serotype 11A variants of genotypes ST838 and ST6521 closely related to the Spain9V-ST156 clone were first detected in 2005. A different pattern of evasion of complement immunity and phagocytosis was observed between genotypes. The emergence of one vaccine escape variant of Spain9V-ST156 (ST652111A), showing a high potential to avoid the host immune response, was observed. In addition, isolates of ST652111A showed higher ability to produce biofilms than ST83811A or ST6211A, which may have contributed to the emergence of this PEN-resistant ST652111A genotype in the last few years. The emergence of penicillin-resistant 11A invasive variants of the highly successful ST156 clonal complex merits close monitoring. 相似文献
123.
Longitudinal Evaluation of the Structure of Replicating and Circulating Hepatitis C Virus Quasispecies in Nonprogressive Chronic Hepatitis C Patients 下载免费PDF全文
Beatriz Cabot María Martell Juan I. Esteban Maria Piron Teresa Otero Rafael Esteban Jaime Guardia Jordi Gmez 《Journal of virology》2001,75(24):12005-12013
In previous cross-sectional studies, we demonstrated that, in most patients with chronic hepatitis C, the composition and complexity of the circulating hepatitis C virus (HCV) population do not coincide with those of the virus replicating in the liver. In the subgroup of patients with similar complexities in both compartments, the ratio of quasispecies complexity in the liver to that in serum (liver/serum complexity ratio) of paired samples correlated with disease stage. In the present study we investigated the dynamic behavior of viral population parameters in consecutive paired liver and serum samples, obtained 3 to 6 years apart, from four chronic hepatitis C patients with persistently normal transaminases and stable liver histology. We sequenced 359 clones of a genomic fragment encompassing the E2(p7)-NS2 junction, in two consecutive liver-serum sample pairs from the four patients and in four intermediate serum samples from one of the patients. The results show that the liver/serum complexity ratio is not stable but rather fluctuates widely over time. Hence, the liver/serum complexity ratio does not identify a particular group of patients but a particular state of the infecting quasispecies. Phylogenetic analysis and signature mutation patterns showed that virtually all circulating sequences originated from sequences present in the liver specimens. The overall behavior of the circulating viral quasispecies appears to originate from changes in the relative replication kinetics of the large mutant spectrum present in the infected liver. 相似文献
124.
Luming Yang Dal‐Hoe Koo Dawei Li Tao Zhang Jiming Jiang Feishi Luan Susanne S. Renner Elizabeth Hénaff Walter Sanseverino Jordi Garcia‐Mas Josep Casacuberta Douglas A. Senalik Philipp W. Simon Jinfeng Chen Yiqun Weng 《The Plant journal : for cell and molecular biology》2014,77(1):16-30
In the large Cucurbitaceae genus Cucumis, cucumber (C. sativus) is the only species with 2n = 2x = 14 chromosomes. The majority of the remaining species, including melon (C. melo) and the sister species of cucumber, C. hystrix, have 2n = 2x = 24 chromosomes, implying a reduction from n = 12 to n = 7. To understand the underlying mechanisms, we investigated chromosome synteny among cucumber, C. hystrix and melon using integrated and complementary approaches. We identified 14 inversions and a C. hystrix lineage‐specific reciprocal inversion between C. hystrix and melon. The results reveal the location and orientation of 53 C. hystrix syntenic blocks on the seven cucumber chromosomes, and allow us to infer at least 59 chromosome rearrangement events that led to the seven cucumber chromosomes, including five fusions, four translocations, and 50 inversions. The 12 inferred chromosomes (AK1–AK12) of an ancestor similar to melon and C. hystrix had strikingly different evolutionary fates, with cucumber chromosome C1 apparently resulting from insertion of chromosome AK12 into the centromeric region of translocated AK2/AK8, cucumber chromosome C3 originating from a Robertsonian‐like translocation between AK4 and AK6, and cucumber chromosome C5 originating from fusion of AK9 and AK10. Chromosomes C2, C4 and C6 were the result of complex reshuffling of syntenic blocks from three (AK3, AK5 and AK11), three (AK5, AK7 and AK8) and five (AK2, AK3, AK5, AK8 and AK11) ancestral chromosomes, respectively, through 33 fusion, translocation and inversion events. Previous results (Huang, S., Li, R., Zhang, Z. et al., 2009 , Nat. Genet. 41, 1275–1281; Li, D., Cuevas, H.E., Yang, L., Li, Y., Garcia‐Mas, J., Zalapa, J., Staub, J.E., Luan, F., Reddy, U., He, X., Gong, Z., Weng, Y. 2011a, BMC Genomics, 12, 396) showing that cucumber C7 stayed largely intact during the entire evolution of Cucumis are supported. Results from this study allow a fine‐scale understanding of the mechanisms of dysploid chromosome reduction that has not been achieved previously. 相似文献
125.
Emili Saló Ana Maria Muñoz-Mármol José Ramon Bayascas-Ramirez Jordi Garcia-Fernàndez Agusti Miralles Andreu Casali Montserrat Corominas Jaume Baguñá 《Hydrobiologia》1995,305(1-3):269-275
To identify potential pattern control and cell determination and/or differentiation genes in the freshwater planarian Dugesial (G.) tigrina, we searched for homeobox genes of different types in the genome of this primitive metazoan. We applied two basic approaches: 1) Screening the cDNA library with degenerate oligonucleotides corresponding to the most conserved amino acid sequence from helix-3 of the homeodomain of each family; and 2) PCR amplification of genomic DNA or cDNA, using two sets of degenerated oligonucleotides corresponding to helices 1 and 3 of the homeodomain or two specific domains of the POU family. Using the first strategy we have identified and characterized two tissue-specific cell determination and/or differentiation NK-type homeobox genes. Using the second strategy we have identified several homeobox genes that belong to the HOM/Hox, paired (prd) or POU families. 相似文献
126.
Manel Puig-Domingo Raúl M. Luque Jordi L. Reverter Laura M. López-Sánchez Manuel D. Gahete Michael D. Culler Gonzalo Díaz-Soto Francisco Lome?a Mattia Squarcia José Luis Mate Mireia Mora Laureano Fernández-Cruz Oscar Vidal Antonio Alastrué Jose Balibrea Irene Halperin Dídac Mauricio Justo P. Casta?o 《PloS one》2014,9(1)
Somatostatin receptors (ssts) are expressed in thyroid cancer cells, but their biological significance is not well understood. The aim of this study was to assess ssts in well differentiated (WDTC) and poorly differentiated thyroid cancer (PDTC) by means of imaging and molecular tools and its relationship with the efficacy of somatostatin analog treatment. Thirty-nine cases of thyroid carcinoma were evaluated (20 PDTC and 19 WDTC). Depreotide scintigraphy and mRNA levels of sst-subtypes, including the truncated variant sst5TMD4, were carried out. Depreotide scans were positive in the recurrent tumor in the neck in 6 of 11 (54%) PDTC, and in those with lung metastases in 5/11 cases (45.4%); sst5TMD4 was present in 18/20 (90%) of PDTC, being the most densely expressed sst-subtype, with a 20-fold increase in relation to sst2. In WDTC, sst2 was the most represented, while sst5TMD4 was not found; sst2 was significantly increased in PDTC in comparison to WDTC. Five depreotide positive PDTC received octreotide for 3–6 months in a pilot study with no changes in the size of the lesions in 3 of them, and a significant increase in the pulmonary and cervical lesions in the other 2. All PDTC patients treated with octreotide showed high expression of sst5TMD4. ROC curve analysis demonstrated that only sst5TMD4 discriminates between PDTC and WDTC. We conclude that sst5TMD4 is overexpressed in PDTC and may be involved in the lack of response to somatostatin analogue treatment. 相似文献
127.
The monitoring of gene expression is fundamental for understanding developmental biology. Here we report a successful experimental
protocol for in situ hybridization in both whole-mount and sectioned planarian embryos. Conventional in situ hybridization
techniques in developmental biology are used on whole-mount preparations. However, given that the inherent lack of external
morphological markers in planarian embryos hinders the proper interpretation of gene expression data in whole-mount preparations,
here we used sectioned material. We discuss the advantages of sectioned versus whole-mount preparations, namely, better probe
penetration, improved tissue preservation, and the possibility to interpret gene expression in relation to internal morphological
markers such as the epidermis, the embryonic and definitive pharynges, and the gastrodermis. Optimal fixatives and embedding
methods for sectioning are also discussed.
A. Cardona and J. Fernández have contributed equally to this work. 相似文献
128.
129.
Raquel Benavides Sonia G. Rabasa Elena Granda Adrián Escudero José A. Hódar Jordi Martínez-Vilalta Ana M. Rincón Regino Zamora Fernando Valladares 《PloS one》2013,8(3)
Global change triggers shifts in forest composition, with warming and aridification being particularly threatening for the populations located at the rear edge of the species distributions. This is the case of Scots pine (Pinus sylvestris) in the Mediterranean Basin where uncertainties in relation to its dynamics under these changing scenarios are still high. We analysed the relative effect of climate on the recruitment patterns of Scots pine and its interactions with local biotic and abiotic variables at different spatial scales. Number of seedlings and saplings was surveyed, and their annual shoot growth measured in 96 plots located across altitudinal gradients in three different regions in the Iberian Peninsula. We found a significant influence of climate on demography and performance of recruits, with a non-linear effect of temperature on the presence of juveniles, and a positive effect of precipitation on their survival. Abundance of juveniles of P. sylvestris that underwent their first summer drought was skewed towards higher altitudes than the altitudinal mean range of the conspecific adults and the optimum elevation for seedlings'' emergence. At local level, light availability did not influence juveniles'' density, but it enhanced their growth. Biotic interactions were found between juveniles and the herb cover (competition) and between the number of newly emerged seedlings and shrubs (facilitation). Results also highlighted the indirect effect that climate exerts over the local factors, modulating the interactions with the pre-existing vegetation that were more evident at more stressful sites. This multiscale approach improves our understanding of the dynamics of these marginal populations and some management criteria can be inferred to boost their conservation under the current global warming. 相似文献