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11.
Sarai Belchí-Navarro Lorena Almagro Ana Belén Sabater-Jara Francisco Fernández-Pérez Roque Bru Maria Angeles Pedreño 《Journal of plant physiology》2013
Suspension-cultured cells of Vitis vinifera cv Monastrell were used to investigate the effects of methyljasmonate, ethylene and salicylic acid separately or in combination with cyclodextrins on both trans-resveratrol production and the induction of defense responses. 相似文献
12.
Pollen grains of 20 taxa from Gochnatia , Ianthopappus , and Richterago (Compositae - Mutisieae) have been studied. Pollen morphological characters and intergeneric differences are described. Pollen of grains of Richterago and Ianthopappus are relatively larger with thickened exine in the mesocolpia and possess coarse, supratectal spinuliferous processes the height of which is less than their diameter at the base. In Gochnatia , the pollen is medium-sized, the exine is not thickened in the mesocolpia and has minute supratectal spinuliferous processes the height of which is equal or slightly more than 3 w m. Ianthopappus corymbosus is the only species in which the infratectum is thicker than the tectum. With reference to the pollen size and the exine thickness this species appears phylogenetically closer to Richterago than to Gochnatia . 相似文献
13.
Javier Prieto Marian León Xavier Ponsoda Francisco García-García Roque Bort Eva Serna 《Cell cycle (Georgetown, Tex.)》2016,15(23):3240-3250
We have recently shown that mitochondrial fission is induced early in reprogramming in a Drp1-dependent manner; however, the identity of the factors controlling Drp1 recruitment to mitochondria was unexplored. To investigate this, we used a panel of RNAi targeting factors involved in the regulation of mitochondrial dynamics and we observed that MiD51, Gdap1 and, to a lesser extent, Mff were found to play key roles in this process. Cells derived from Gdap1-null mice were used to further explore the role of this factor in cell reprogramming. Microarray data revealed a prominent down-regulation of cell cycle pathways in Gdap1-null cells early in reprogramming and cell cycle profiling uncovered a G2/M growth arrest in Gdap1-null cells undergoing reprogramming. High-Content analysis showed that this growth arrest was DNA damage-independent. We propose that lack of efficient mitochondrial fission impairs cell reprogramming by interfering with cell cycle progression in a DNA damage-independent manner. 相似文献
14.
M. T. Aguado C. Noreña L. Alcaraz D. Marquina F. Brusa C. Damborenea B. Almon C. Bleidorn C. Grande 《Organisms Diversity & Evolution》2017,17(4):767-778
A phylogenetic analysis of Polycladida based on two partial mitochondrial genes (cox1 and 16S) is provided. The analysis includes 30 polyclad terminals that represent species from the two taxa which traditionally divide the groups Cotylea and Acotylea. Our phylogenetic analyses produced a well-supported hypothesis that confirms the monophyly of Polycladida, as well as Acotylea and Cotylea. Within Acotylea, there are two lineages not highly supported: on one hand, Leptoplanoidea (excluding Hoploplana elisabelloi) and one Stylochoidea member (Pseudostylochus intermedius) (classification sensu Faubel, 1983, 1984), and on the other hand, Stylochoidea members together with Discocelis tigrina and H. elisabelloi. The genera Stylochus and Imogine are not monophyletic. Within Cotylea, Pseudocerotidae and Euryleptidae are monophyletic, though not highly supported, while Prosthiostomidae is not. Euryleptoidea is paraphyletic. The genera Pseudobiceros and Pseudoceros are monophyletic and highly supported. Our results suggest that, within Acotylea, the prostatoid organs of Discocelis may have been derived from a prostatic vesicle. The genus Hoploplana could be included in Stylochoidea. Within Cotylea, the common ancestor of Euryleptidae and Pseudocerotidae might have been an aposematic animal with tentacles. 相似文献
15.
Roque JB O'Leary CA Duffy DL Kyaw-Tanner M Latter M Mason K Vogelnest L Shipstone M 《The Journal of heredity》2011,102(Z1):S74-S80
Immunoglobulin E (IgE)-mediated hypersensitivity against environmental allergens, commonly including Dermatophagoides farinae, is associated with atopic diseases in both humans and dogs. We have recently identified a family of clinically healthy West Highland white terriers (WHWTs) with high-serum D. farinae-IgE levels. In this study, we investigated the genetic mechanism controlling IgE responsiveness in dogs by performing a genome-wide association study (GWAS) using the Affymetrix V2 Dog SNP array in 31 high-IgE and 24 low-IgE responder WHWTs. A gene-dropping simulation method, using SIB-PAIR software, showed significant allelic association between serum D. farinae-specific IgE levels and a 2.3-Mb area on CFA35 (best empirical P = 1 × 10(-5)). A nearby candidate gene, CD83, encodes a protein which has important immunological functions in antigen presentation and regulation of humoral immune responses. We sequenced this gene in 2 high-IgE responders and 2 low-IgE responders and identified an intronic polymorphic repeat sequence with a predicted functional effect, but the association was insufficient to explain the GWAS association signal in this population (P = 1 × 10(-3)). Further studies are necessary to investigate the significance of these findings for IgE responsiveness and atopic disease in the dog. 相似文献
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18.
Miguel ángel Rubio Mauro Napolitano Jesús?A.?G. Ochoa?de?Alda Javier Santamaría-Gómez Carl J. Patterson Andrew W. Foster Roque Bru-Martínez Nigel J. Robinson Ignacio Luque 《Nucleic acids research》2015,43(20):9905-9917
Aminoacyl-tRNA synthetases (aaRSs) play a key role in deciphering the genetic message by producing charged tRNAs and are equipped with proofreading mechanisms to ensure correct pairing of tRNAs with their cognate amino acid. Duplicated aaRSs are very frequent in Nature, with 25,913 cases observed in 26,837 genomes. The oligomeric nature of many aaRSs raises the question of how the functioning and oligomerization of duplicated enzymes is organized. We characterized this issue in a model prokaryotic organism that expresses two different threonyl-tRNA synthetases, responsible for Thr-tRNAThr synthesis: one accurate and constitutively expressed (T1) and another (T2) with impaired proofreading activity that also generates mischarged Ser-tRNAThr. Low zinc promotes dissociation of dimeric T1 into monomers deprived of aminoacylation activity and simultaneous induction of T2, which is active for aminoacylation under low zinc. T2 either forms homodimers or heterodimerizes with T1 subunits that provide essential proofreading activity in trans. These findings evidence that in organisms with duplicated genes, cells can orchestrate the assemblage of aaRSs oligomers that meet the necessities of the cell in each situation. We propose that controlled oligomerization of duplicated aaRSs is an adaptive mechanism that can potentially be expanded to the plethora of organisms with duplicated oligomeric aaRSs. 相似文献
19.
The neural pathway most related with ovarian steroidogenesis has been identified as the superior ovarian nerve (SON). This work constitutes the first study of the effects of early ovarian SON transection, which was performed in rats of 4 days of age (SON-t rats) to magnify the effects of the denervation. The rats were studied at the prepubertal (30 days), peripubertal (41 days) and adult cyclic in dioestrus (60 days) reproductive stages. The SON-t rats showed a delay of vaginal opening, a notable disruption of oestrous cyclicity, and a large number of corpora lutea. In all the stages, the circulating levels of FSH, prolactin and growth hormone were lower in SON-t rats than in controls, whereas LH did not vary. Serum androstenedione levels were higher in SON-t rats at 30 days and lower at 41 days, compared with control animals while no difference was observed at 60 days. Serum progesterone levels did not differ between control and SON-t, but serum oestradiol concentrations were higher in SON-t rats in all of the stages. At the peripubertal stage, there were fewer ovarian beta-adrenergic receptors in SON-t ovaries, associated with a rise in the ovarian content of norepinephrine, but no changes were observed in SON-t rats at 30 and 60 days with respect to the controls. The release of progesterone in vitro from luteal cell in SON-t rats at 60 days was reduced in basal condition and under ovine LH or FSH stimulation, when compared with control animals; while no difference was observed in presence of isoproterenol or androstenedione in the culture medium. In corpora lutea of SON-t rats at 60 days, no change was observed in the activity of 3beta-hydroxysteroid dehydrogenase (3beta-HSD), but the activity of 20alpha-hydroxysteroid dehydrogenase (20alpha-HSD) was reduced, suggesting abnormal luteolysis in spite of the large number of corpora lutea. The interruption of innervation at an early age by SON transection is very important in the regulation of ovarian development in prepubertal and cyclic rats. The functional changes observed in the ovary suggest a possible alteration in the hypothalamic-hypophyseal axis. 相似文献
20.
Following increasing calls for environmental safety over the past 2 decades, persistent pesticides are being replaced by more rapidly degradable products. However, even these pesticides can affect non-target species, and may be associated with slow growth and increased susceptibility to viral and bacterial infections. In this study, juvenile white shrimp Litopenaeus vannamei (also named Penaeus vannamei) were challenged by intramuscular injection with Vibrio parahaemolyticus after 4 d prior exposure to methyl parathion in feed pellets at 0.080 microg g(-1). The bacterial injection control group consisted of shrimp fed pellets containing the methyl parathion-carrier solvent acetonitrile. Three additional control groups comprised 2 sterile saline-injection groups fed pellets containing methyl parathion or acetonitrile prior to injection, and 1 uninjected group fed normal pellets. Cumulative mortalities were recorded on the 4th and 8th days, and the presence of histological lesions was recorded on the 8th day. Cumulative mortalities were significantly higher in the group exposed to methyl parathion and bacteria on Day 8. Histological lesions, typical of vibriosis, were significantly associated with the injection of V. parahaemolyticus. The study provides strong experimental evidence that prior exposure to methyl parathion can increase the severity of Vibrio infections. 相似文献