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981.
Xu Zhang Wei Wu Youliang Zheng Li Chen Cai Qianrong 《Plant Systematics and Evolution》2009,279(1-4):1-10
Three processes play an important role in plant speciation: isolation, hybridization and polyploidization. Galapagos endemic Opuntia display putatively all of these processes. On this archipelago most islands are inhabited by a single Opuntia taxon. Santa Cruz, however, houses two morphologically distinct O. echios varieties (echios and gigantea). Morphological intermediates are found where these two geographically isolated varieties meet. Here we used ten microsatellite loci to reveal the population genetic structure of this system. In contrast to earlier studies, we found high genetic variability within localities. Genetic structuring was weak and no evidence for the existence of hybrids was found. The reasons for this weak genetic structure may include: the species’ hexaploid nature, high levels of gene flow, recent colonization, and the lack of geographic barriers. This first detailed genetic study on these threatened species will be important for further conservation planning. 相似文献
982.
983.
984.
Background
Bacteriocins are very diverse group of antimicrobial peptides produced by a wide range of bacteria and known for their inhibitory activity against various human and animal pathogens. Although many bacteriocins are now well characterized, much information is still missing or is unavailable to potential users. The assembly of such information in one central resource such as a database would therefore be of great benefit to the exploitation of these bioactive molecules in the present context of increasing antibiotic resistance and natural bio-preservation need. 相似文献985.
986.
Frances M Dupont 《BMC plant biology》2008,8(1):39
Background
By definition, amyloplasts are plastids specialized for starch production. However, a proteomic study of amyloplasts isolated from wheat (Triticum aestivum Butte 86) endosperm at 10 days after anthesis (DPA) detected enzymes from many other metabolic and biosynthetic pathways. To better understand the role of amyloplasts in food production, the data from that study were evaluated in detail and an amyloplast metabolic map was outlined. 相似文献987.
Davoud Nouri Inanlou Bagher Yakhchali Hossein Khanahmad Mossa Gardaneh Hesam Movassagh Reza Ahangari Cohan Mehdi Shafiee Ardestani Reza Mahdian Sirous Zeinali 《Biotechnology letters》2010,32(11):1615-1621
We have developed an integrase-defective lentiviral (LV) vector in combination with a gene-targeting approach for gene therapy
of β-thalassemia. The β-globin gene-targeting construct has two homologous stems including sequence upstream and downstream
of the β-globin gene, a β-globin gene positioned between hygromycin and neomycin resistant genes and a herpes simplex virus
type 1 thymidine kinase (HSVtk) suicide gene. Utilization of integrase-defective LV as a vector for the β-globin gene increased the number of selected clones
relative to non-viral methods. This method represents an important step toward the ultimate goal of a clinical gene therapy
for β-thalassemia. 相似文献
988.
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
989.
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
990.