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881.
The response to signals, including scent marks, from opposite-sex conspecifics can be affected by the nutritional state of
both the sender and receiver of these signals. Protein content of the diet affects how meadow voles (Microtus pennsylvanicus) respond to single scent marks, but it is unknown how it affects an individual’s response to the overlapping scent marks
of two donors (an over-mark). In experiment 1, we tested the hypothesis that protein content of the diet affects the amount
of time voles spend investigating the marks of the top- and bottom-scent donors of an over-mark. Males and females fed a 22%
protein diet spent more time investigating the scent mark of the top-scent donor than that of the bottom-scent donor; voles
fed 9% and 13% protein diets spent similar amounts of time investigating the top- and bottom-scent donors. In experiment 2,
we tested the hypothesis that protein content of the diet of the top- and bottom-scent donors affects the amount of time conspecifics
spend investigating their scent marks. Female voles spent more time investigating the mark of the top-scent male than that
of the bottom-scent male, independent of the differences in protein content of the diets of the top- and bottom-scent donors.
Male voles, however, spent more time investigating the top-scent female when she was fed a diet higher in protein content
than that of the bottom-scent female. Our results are discussed within the context of the natural history of voles. 相似文献
882.
Jing Zhang Ga Liao Chang Liu Lei Sun Yanyou Liu Yuhui Wang Zhou Jiang Zhengrong Wang 《Molecular biology reports》2011,38(1):349-354
Many reports have shown that the biologic rhythm could be altered due to mutations of circadian gene hClock or hPeriod, and
the mutations of circadian genes have some relationship with psychosis according to recent studies. A preliminary study has
been conducted to examine wether the T3111C single nucleotide polymorphism of the hClock gene or the length polymorphism of
the hPer3 gene is associated with the development of schizophrenia. The samples from schizophrenics (n = 148, male: 57.4%, female: 42.6%) and normal controls (n = 199, male: 59.3%, female: 40.7%) were examined. Allele frequencies of T3111C SNP of hClock were significantly different
between schizophrenics and controls (χ2 = 19.738, P < 0.05). Schizophrenics had a significantly higher frequency of the C allele compared with controls (OR = 2.613, 95% CI = 1.693–4.034).
On the other hand, there is no significant difference of allele frequencies of 18 exon of hper3 between schizophrenics and controls (χ2 = 0.192, P > 0.05). Our results suggest that the T3111C (RS1801260) polymorphism of hClock gene is associated with schizophrenia, but
it seems that the length polymorphism of 18 exon of hPer3 may not be associated with schizophrenia. It is important to address
of the relationship between circadian gene polymorphisms and dopamine functions in further study. 相似文献
883.
884.
Gene delivery by lentivirus vectors 总被引:13,自引:0,他引:13
The capacity to efficiently transduce nondividing cells, shuttle large genetic payloads, and maintain stable long-term transgene
expression are attributes that have brought lentiviral vectors to the forefront of gene delivery vehicles for research and
therapeutic applications in a clinical setting. Our discussion initiates with advances in lentiviral vector development and
how these sophisticated lentiviral vectors reflect improvements in safety, regarding the prevention of replication competent
lentiviruses (RCLs), vector mobilization, and insertional mutagenesis. Additionally, we describe conventional molecular regulatory
systems to manage gene expression levels in a spatial and temporal fashion in the context of a lentiviral vector. State of
the art technology for lentiviral vector production by transient transfection and packaging cell lines are explicitly presented
with current practices used for concentration, purification, titering, and determining the safety of a vector stock. We summarize
lentiviral vector applications that have received a great deal of attention in recent years including the generation of transgenic
animals and the stable delivery of RNA interference molecules. Concluding remarks address some of the successes in preclinical
animals, and the recent transition of lentiviral vectors to human clinical trials as therapy for a variety of infectious and
genetic diseases. 相似文献
885.
Cooperation within Actin Filament in Vertebrate Skeletal Muscle 总被引:56,自引:0,他引:56
When actin molecules form “rigor complexes” with nucleotide-free myosin, tropomn binds calcium with greater affinity and in a cooperative response the remaining actin molecules not cornplexed with myosin are “turned on” even though calcium is absent. 相似文献
886.
Joana L. A. Brás Victor D. Alves Ana Luísa Carvalho Shabir Najmudin José A. M. Prates Luís M. A. Ferreira David N. Bolam Maria Jo?o Rom?o Harry J. Gilbert Carlos M. G. A. Fontes 《The Journal of biological chemistry》2012,287(53):44394-44405
Protein-protein interactions play a pivotal role in a large number of biological processes exemplified by the assembly of the cellulosome. Integration of cellulosomal components occurs through the binding of type I cohesin modules located in a non-catalytic molecular scaffold to type I dockerin modules located at the C terminus of cellulosomal enzymes. The majority of type I dockerins display internal symmetry reflected by the presence of two essentially identical cohesin-binding surfaces. Here we report the crystal structures of two novel Clostridium thermocellum type I cohesin-dockerin complexes (CohOlpC-Doc124A and CohOlpA-Doc918). The data revealed that the two dockerins, Doc918 and Doc124A, are unusual because they lack the structural symmetry required to support a dual binding mode. Thus, in both cases, cohesin recognition is dominated by residues located at positions 11, 12, and 19 of one of the dockerin binding surfaces. The alternative binding mode is not possible (Doc918) or highly limited (Doc124A) because residues that assume the critical interacting positions, when dockerins are reoriented by 180°, make steric clashes with the cohesin. In common with a third dockerin (Doc258) that also presents a single binding mode, Doc124A directs the appended cellulase, Cel124A, to the surface of C. thermocellum and not to cellulosomes because it binds preferentially to type I cohesins located at the cell envelope. Although there are a few exceptions, such as Doc918 described here, these data suggest that there is considerable selective pressure for the evolution of a dual binding mode in type I dockerins that direct enzymes into cellulosomes. 相似文献
887.
888.
Ae-Young Mo Bora Kwon Seralathan Kamala-Kannan Kui-Jae Lee Byung-Taek Oh Dae-Hyuk Kim Moon-Sik Yang Jin-Hyung Kim Seung-Moon Park 《World journal of microbiology & biotechnology》2010,26(6):1099-1105
Bacteria of the Bacillus species have been reported as an important microorganism in fermented soybean products. In the present study, thirty Bacillus isolates were screened from Meju, a Korean soybean fermentation starter. The comparative analysis of 16S rDNA sequences, 16S-23S internal transcribed spacer
sequences, phenotypic, and biochemical characterizations revealed three phylogenetically distinct groups namely Bacillus atrophaeus,
Bacillus polyfermenticus and Bacillus subtilis. The isolates were assayed for poly-γ-glutamate production and fibrinolytic activity. Among the isolates, B. polyfermenticus exhibited maximum poly-γ-glutamate production and fibrinolytic activity. Moreover, the soybean products fermented by B. polyfermenticus have increased the time taken for coagulation and hemorrhage in mice. The results of the present study clearly indicate the
functional role of B. polyfermenticus in fermented soybean products. 相似文献
889.
Genomewide association studies (GWAS) have proven a powerful hypothesis-free method to identify common disease-associated
variants. Even quite large GWAS, however, have only at best identified moderate proportions of the genetic variants contributing
to disease heritability. To provide cost-effective genotyping of common and rare variants to map the remaining heritability
and to fine-map established loci, the Immunochip Consortium has developed a 200,000 SNP chip that has been produced in very
large numbers for a fraction of the cost of GWAS chips. This chip provides a powerful tool for immunogenetics gene mapping. 相似文献
890.
Fernández-Acero FJ Jorge I Calvo E Vallejo I Carbú M Camafeita E Garrido C López JA Jorrin J Cantoral JM 《Archives of microbiology》2007,187(3):207-215
Botrytis cinerea is a phytopathogenic fungus causing disease in a substantial number of economically important crops. In an attempt to identify putative fungal virulence factors, the two-dimensional gel electrophoresis (2-DE) protein profile
from two B. cinerea strains differing in virulence and toxin production were compared. Protein extracts from fungal mycelium obtained by tissue
homogenization were analyzed. The mycelial 2-DE protein profile revealed the existence of qualitative and quantitative differences
between the analyzed strains. The lack of genomic data from B. cinerea required the use of peptide fragmentation data from MALDI-TOF/TOF and ESI ion trap for protein identification, resulting
in the identification of 27 protein spots. A significant number of spots were identified as malate dehydrogenase (MDH) and
glyceraldehyde-3-phosphate dehydrogenase (GAPDH). The different expression patterns revealed by some of the identified proteins
could be ascribed to differences in virulence between strains. Our results indicate that proteomic analysis are becoming an
important tool to be used as a starting point for identifying new pathogenicity factors, therapeutic targets and for basic
research on this plant pathogen in the postgenomic era. 相似文献