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171.
Bjorn Kloosterman AM Anithakumari Pierre-Yves Chibon Marian Oortwijn Gerard C van der Linden Richard GF Visser Christian WB Bachem 《BMC plant biology》2012,12(1):17
Background
With the completion of genome sequences belonging to some of the major crop plants, new challenges arise to utilize this data for crop improvement and increased food security. The field of genetical genomics has the potential to identify genes displaying heritable differential expression associated to important phenotypic traits. Here we describe the identification of expression QTLs (eQTLs) in two different potato tissues of a segregating potato population and query the potato genome sequence to differentiate between cis- and trans-acting eQTLs in relation to gene subfunctionalization. 相似文献172.
Begossi A Salyvonchyk S Nora V Lopes PF Silvano RA 《Journal of ethnobiology and ethnomedicine》2012,8(1):22-19
ABSTRACT: This study intends to give recommendations to the management of Paraty fishery in Brazil through an interplay of local and scientific knowledge. In particular, the objectives are the following: 1) to describe the Paraty fishery; 2) to compare the fishermen's local ecological knowledge with recorded fish landings and previous studies in Paraty; 3) to combine the data on local fishing and on local/Caicara livelihoods with the SES (social-ecological systems) Model. The methods include a systematic survey of fishing in Tarituba and Praia Grande, which are located in the northern end and the central part of the Paraty municipality, respectively. For four days each month, systematic data on catches at landing points were collected, as well as macroscopic gonad analysis data for the fishes Centropomus parallelus and C. undecimalis (snook, robalo), Epinephelus marginatus (grouper, garoupa), Scomberomorus cavalla (King mackerel, cavala), and Lutjanus synagris (Lane snapper, vermelho). Spring and summer are important seasons during which some species reproduce, and the integration of fishing periods for some target species could assist in fishing management through the use of closed seasons. Fishermen could obtain complementary earnings from tourism and from the "defeso system" (closed season including a salary payment) to conserve fishing stocks. The SES model facilitates an understanding of the historical context of fishing, its economic importance for local livelihoods, the constraints from conservation measures that affect fishermen, and the management processes that already exist, such as the defeso. If used to integrate fishing with complementary activities (tourism), such a system could improve the responsibility of fishermen regarding the conservation of fish stocks. 相似文献
173.
Killer immunoglobulin‐like receptor repertoire analysis in a Caucasian Spanish cohort with inflammatory bowel disease 下载免费PDF全文
Ruth López‐Hernández Jose A. Campillo Isabel Legaz Mariano Valdés Hortensia Salama Francisco Boix AM Hernández‐Martínez Jorge Eguia G González‐Martínez Maria R. Moya‐Quiles Alfredo Minguela Ana García‐Alonso Fernando Carballo Manuel Muro 《Microbiology and immunology》2016,60(11):787-792
Immunological molecules are implicated in inflammatory disorders, including inflammatory bowel disease (IBD; Crohn disease [CD] and ulcerative colitis [UC]). Killer cell immunoglobulin‐like receptors (KIRs) are also genetically variable proteins involved in immune function. They are expressed by NK cells and certain T lymphocytes, regulate specificity and function by interaction with HLA Class I molecules, may be either inhibitory or activating and are polymorphic both in terms of alleles and haplotype gene content. Genetic associations between activating KIRs and certain autoimmune and inflammatory diseases have been reported; however, a possible association between KIR and IBD remains unclear. The aim of this study was to determine the relationship between KIR repertoire and IBD pathologies in a Spanish cohort. KIR variability was analyzed using PCR–sequence specific oligonucleotide probes (SSOP). Inhibitory KIR2DL5 was found more frequently in UC and IBD patient groups than in healthy controls (P = 0.028 and P = 0.01, respectively), as was activating KIR2DS1 (P = 0.02, Pc > 0.05, UC vs. Controls; P = 0.001, Pc = 0.01, IBD vs Controls; P = 0.01, Pc > 0.05, Controls vs CR), KIR2DS5 (P = 0.0028, Pc = 0.04, Controls vs UC; P = 0.0001, Pc = 0.0017, Controls vs IBD; P = 0.01, Pc > 0.05, Controls vs CD) and KIR3DS1 (P = 0.012, Pc > 0.05, Controls vs IBD). Our data suggest that imbalance between activating and inhibitory KIR may partially explain the different pathogeneses of these IBDs and that there is a hypothetical role for the telomeric B region (which contains both KIR2DS5 and KIR2DS1) in these diseases. 相似文献
174.
Rute ST Martins Laurence AM Deloffre Constantinos C Mylonas Deborah M Power Adelino VM Canário 《Reproductive biology and endocrinology : RB&E》2007,5(1):19
Background
DAX1 (NR0B1), a member of the nuclear receptors super family, has been shown to be involved in the genetic sex determination and in gonadal differentiation in several vertebrate species. In the aquaculture fish European sea bass, Dicentrarchus labrax, and in the generality of fish species, the mechanisms of sex determination and differentiation have not been elucidated. The present study aimed at characterizing the European DAX1 gene and its developmental expression at the mRNA level. 相似文献175.
MANO SABARATN AM 《The Journal of eukaryotic microbiology》1971,18(1):141-146
SYNOPSIS. Gregarina fernandoi n. sp. is a eugregarine. Its structure, development and life history in the gut of the cockroach Pycnoscelus surinamensis are described. It is named as a new species on the basis of its size, nuclear structure, structure and form of the gametocyst and oocyst. Observations were made on the different stages of the parasite and related to the pH of the gut. In the ceca, pH 4.5–5, the parasite was in its early stages of development, in the midgut, pH 6.5–7, it was in syzygy and in the rectum, pH 7.5–8, gametocysts were found. 相似文献
176.
177.
Short repetitive sequences in green algal mitochondrial genomes: potential roles in mitochondrial genome evolution 总被引:4,自引:2,他引:2
Current data on green algal mitochondrial genomes suggest an unexpected
dichotomy within the group with respect to genome structure, organization,
and sequence affiliations. The present study suggests that there is a
correlation between this dichotomy on one hand and the differences in the
abundance, base composition, and distribution of short repetitive sequences
we observed among green algal mitochondrial genomes on the other. It is
conceivable that the accumulation of GC- rich short repeated sequences in
the Chlamydomonas-like but not Prototheca-like mitochondrial genomes might
have triggered evolutionary events responsible for the distinct series of
evolutionary changes undergone by the two green algal mitochondrial
lineages. The similarity in base composition, nucleotide sequence,
abundance, and mode of organization we observed between the short
repetitive sequences present in Chlamydomonas-like mitochondrial genomes on
one hand and fungal and vertebrate homologs on the other might extend to
some of the roles that the short repetitive sequences have been shown to
have in the latter. Potential involvements we propose for the short
repetitive sequences in the evolution of Chlamydomonas-like mitochondrial
genomes include fragmentation and scrambling of the ribosomal-RNA-coding
regions, extensive gene rearrangements, coding-region deletions, surrogate
origins of replication, and chromosomal linearization.
相似文献
178.
A. terreus isolates isolated from some bakery products, corn and rice were found to be able to produce territrems. 90% of theA. terreus isolated from bakery products were able to produce territrem A, with a mean of 0.09 ppm, while 80% ofA. terreus isolates produce territrem B with a mean of 0.24 ppm. On the other hand 31.8% of the isolates ofA. terreus from corn were able to produce territrem A with a mean of 0.44 ppm. ConcerningA. terreus isolates from rice, 66.7% were found to produce territrem A, with a mean of 5.28 ppm, and 77.8% of the isolates produced
territrem B with a mean of 1.79 ppm. 相似文献
179.
High copy number of highly similar mariner-like transposons in planarian (Platyhelminthe): evidence for a trans-phyla horizontal transfer 总被引:8,自引:2,他引:6
Garcia-Fernandez J; Bayascas-Ramirez JR; Marfany G; Munoz-Marmol AM; Casali A; Baguna J; Salo E 《Molecular biology and evolution》1995,12(3):421-431
Several DNA sequences similar to the mariner element were isolated and
characterized in the platyhelminthe Dugesia (Girardia) tigrina. They were
1,288 bp long, flanked by two 32 bp-inverted repeats, and contained a
single 339 amino acid open-reading frame (ORF) encoding the transposase.
The number of copies of this element is approximately 8,000 per haploid
genome, constituting a member of the middle- repetitive DNA of Dugesia
tigrina. Sequence analysis of several elements showed a high percentage of
conservation between the different copies. Most of them presented an intact
ORF and the standard signals of actively expressed genes, which suggests
that some of them are or have recently been functional transposons. The
high degree of similarity shared with other mariner elements from some
arthropods, together with the fact that this element is undetectable in
other planarian species, strongly suggests a case of horizontal transfer
between these two distant phyla.
相似文献
180.
Assessing horizontal transfer of nifHDK genes in eubacteria: nucleotide sequence of nifK from Frankia strain HFPCcI3 总被引:2,自引:1,他引:1
Hirsch AM; McKhann HI; Reddy A; Liao J; Fang Y; Marshall CR 《Molecular biology and evolution》1995,12(1):16-27
The structural genes for nitrogenase, nifK, nifD, and nifH, are crucial for
nitrogen fixation. Previous phylogenetic analysis of the amino acid
sequence of nifH suggested that this gene had been horizontally transferred
from a proteobacterium to the gram-positive/cyanobacterial clade, although
the confounding effects of paralogous comparisons made interpretation of
the data difficult. An additional test of nif gene horizontal transfer
using nifD was made, but the NifD phylogeny lacked resolution. Here nif
gene phylogeny is addressed with a phylogenetic analysis of a third and
longer nif gene, nifK. As part of the study, the nifK gene of the key taxon
Frankia was sequenced. Parsimony and some distance analyses of the nifK
amino acid sequences provide support for vertical descent of nifK, but
other distance trees provide support for the lateral transfer of the gene.
Bootstrap support was found for both hypotheses in all trees; the nifK data
do not definitively favor one or the other hypothesis. A parsimony analysis
of NifH provides support for horizontal transfer in accord with previous
reports, although bootstrap analysis also shows some support for vertical
descent of the orthologous nifH genes. A wider sampling of taxa and more
sophisticated methods of phylogenetic inference are needed to understand
the evolution of nif genes. The nif genes may also be powerful phylogenetic
tools. If nifK evolved by vertical descent, it provides strong evidence
that the cyanobacteria and proteobacteria are sister groups to the
exclusion of the firmicutes, whereas 16S rRNA sequences are unable to
resolve the relationships of these three major eubacterial lineages.
相似文献