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91.
A 17 bp deletion in the Bone Morphogenetic Protein 15 (BMP15) gene is associated to increased prolificacy in the Rasa Aragonesa sheep breed 总被引:2,自引:0,他引:2
Monteagudo LV Ponz R Tejedor MT Laviña A Sierra I 《Animal reproduction science》2009,110(1-2):139-146
Different mutations in the Bone Morphogenetic Protein 15 (BMP15) and the Growth Differentiation Factor 9 (GDF9) genes cause increased ovulation rate and infertility in a dosage-sensitive manner in sheep. They cause increased ovulation rate and twin and triplet births in heterozygotes, and complete primary ovarian failure in homozygotes resulting in total infertility. We are here presenting a novel mutation in the second exon of the ovine BMP15 gene, found in the Spanish breed Rasa Aragonesa. It consists of a 17 bp deletion resulting in displacement of the open reading frame and premature stop codons. As a consequence, nearly 85% of the sequence of the wild type aminoacidic chain in the second exon of the BMP15 pro-protein is modified or suppressed as only the first 45 amino acids are conserved of the 245 original. The mature peptide is lost. The ewes heterozygous for this deletion present very high prolificacy (2.66 lambs/birth) when compared to a mean flock prolificacy of 1.36 lambs. The deletion causes a complete lack of functionality of the second exon of BMP15, comparable to the effect of premature stop codons in other mutations. Therefore, homozygous females for the deletion are expected to present primary ovarian failure. DNA sequence analysis of the GDF9 coding regions detected only a synonymous Single Nucleotide Polymorphism (SNP), apparently not linked to changes in prolificacy. 相似文献
92.
Short‐term lime pretreatment uses lime and high‐pressure oxygen to significantly increase the digestibility of poplar wood. When the treated poplar wood was enzymatically hydrolyzed, glucan and xylan were converted to glucose and xylose, respectively. To calculate product yields from raw biomass, these sugars were expressed as equivalent glucan and xylan. To recommend pretreatment conditions, the single criterion was the maximum overall glucan and xylan yields using a cellulase loading of 15 FPU/g glucan in raw biomass. On this basis, the recommended conditions for short‐term lime pretreatment of poplar wood follow: (1) 2 h, 140°C, 21.7 bar absolute and (2) 2 h, 160°C, and 14.8 bar absolute. In these two cases, the reactivity was nearly identical, thus the selected condition depends on the economic trade off between pressure and temperature. Considering glucose and xylose and their oligomers produced during 72 h of enzymatic hydrolysis, the overall yields attained under these recommended conditions follow: (1) 95.5 g glucan/100 g of glucan in raw biomass and 73.1 g xylan/100 g xylan in raw biomass and (2) 94.2 g glucan/100 g glucan in raw biomass and 73.2 g xylan/100 g xylan in raw biomass. The yields improved by increasing the enzyme loading. An optimal enzyme cocktail was identified as 67% cellulase, 12% β‐glucosidase, and 24% xylanase (mass of protein basis) with cellulase activity of 15 FPU/g glucan in raw biomass and total enzyme loading of 51 mg protein/g glucan in raw biomass. Ball milling the lime‐treated poplar wood allowed for 100% conversion of glucan in 120 h with a cellulase loading of only 10 FPU/g glucan in raw biomass. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 相似文献
93.
Basilio A Justice M Harris G Bills G Collado J de la Cruz M Diez MT Hernandez P Liberator P Nielsen kahn J Pelaez F Platas G Schmatz D Shastry M Tormo JR Andersen GR Vicente F 《Bioorganic & medicinal chemistry》2006,14(2):560-566
A novel sordarin derivative, moriniafungin (1), containing a 2-hydroxysebacic acid residue linked to C-3' of the sordarose residue of sordarin through a 1,3-dioxolan-4-one ring was isolated from the fungus Morinia pestalozzioides. Isolation of moriniafungin employed a highly specific bioassay consisting of a panel of Saccharomyces cerevisiae strains containing chimeric eEF2 for Candida glabrata, Candida krusei, Candida lusitaniae, Crytpococcus neoformans, and Aspergillus fumigatus as well as wild type and human eEF2. Moriniafungin exhibited an MIC of 6 microg/mL versus Candida albicans and IC(50)'s ranging from 0.9 to 70 microg/mL against a panel of clinically relevant Candida strains. Moriniafungin was shown to inhibit in vitro translation in the chimeric S. cerevisae strains at levels consistent with the observed IC(50). Moriniafungin has the broadest antifungal spectrum and most potent activity of any natural sordarin analog identified to date. 相似文献
94.
Background
Administration of psychomotor stimulants like amphetamine facilitates behavior in the presence of incentive distal stimuli, which have acquired the motivational properties of primary rewards through associative learning. This facilitation appears to be mediated by the mesolimbic dopamine system, which may also be involved in facilitating behavior in the presence of distal stimuli that have not been previously paired with primary rewards. However, it is unclear whether psychomotor stimulants facilitate behavioral interaction with unconditioned distal stimuli.Principal Findings
We found that noncontingent administration of amphetamine into subregions of the rat ventral striatum, particularly in the vicinity of the medial olfactory tubercle, facilitates lever pressing followed by visual signals that had not been paired with primary rewards. Noncontingent administration of amphetamine failed to facilitate lever pressing when it was followed by either tones or delayed presentation or absence of visual signals, suggesting that visual signals are key for enhanced behavioral interaction. Systemic administration of amphetamine markedly increased locomotor activity, but did not necessarily increase lever pressing rewarded by visual signals, suggesting that lever pressing is not a byproduct of heightened locomotor activity. Lever pressing facilitated by amphetamine was reduced by co-administration of the dopamine receptor antagonists SCH 23390 (D1 selective) or sulpiride (D2 selective).Conclusions
Our results suggest that amphetamine administration into the ventral striatum, particularly in the vicinity of the medial olfactory tubercle, activates dopaminergic mechanisms that strongly enhance behavioral interaction with unconditioned visual stimuli. 相似文献95.
96.
Martínez-Lorenzo MJ Anel A Monleón I Sierra JJ Piñeiro A Naval J Alava MA 《The international journal of biochemistry & cell biology》2000,32(4):435-445
A prominent tyrosine phosphorylated protein of 85 kDa (p85) was detected in highly proliferative sublines derived from the Jurkat T cell leukemia. We undertook a study to characterize the identity of this protein and its possible role in the hyperproliferative phenotypes observed. Using immunoblot and immunoprecipitation techniques, this protein was characterized as the p85 regulatory subunit of phosphatidylinositol 3-kinase. Cell proliferation and p85 tyrosine phosphorylation was not affected by tyrphostin AG-490, an inhibitor of Jak kinases, wortmannin or LY294002, inhibitors of the activity of the catalytic phosphatidylinositol 3-kinase subunit. Herbimycin-A and PPI, inhibitors of src-like protein tyrosine kinases, and genistein, a general tyrosine kinase inhibitor, inhibited p85 tyrosine phosphorylation and induced cell death in the sublines. PD98059, an inhibitor of Mek, inhibited cell growth of the sublines, but not that of the parental cells. It was concluded that tyrosine phosphorylation of p85 is associated with highly proliferative tumoral phenotypes, at least in T cell leukemias, independent of the phosphatidylinositol 3-kinase activity of the catalytic subunit. 相似文献
97.
Zhu Z Burnett CM Maksymov G Stepniak E Sierra A Subbotina E Anderson ME Coetzee WA Hodgson-Zingman DM Zingman LV 《Biochemical and biophysical research communications》2011,(4):637-641
The cardiovascular system operates under demands ranging from conditions of rest to extreme stress. One mechanism of cardiac stress tolerance is action potential duration shortening driven by ATP-sensitive potassium (KATP) channels. KATP channel expression has a significant physiologic impact on action potential duration shortening and myocardial energy consumption in response to physiologic heart rate acceleration. However, the effect of reduced channel expression on action potential duration shortening in response to severe metabolic stress is yet to be established. Here, transgenic mice with myocardium-specific expression of a dominant negative KATP channel subunit were compared with littermate controls. Evaluation of KATP channel whole cell current and channel number/patch was assessed by patch clamp in isolated ventricular cardiomyocytes. Monophasic action potentials were monitored in retrogradely perfused, isolated hearts during the transition to hypoxic perfusate. An 80–85% reduction in cardiac KATP channel current density results in a similar magnitude, but significantly slower rate, of shortening of the ventricular action potential duration in response to severe hypoxia, despite no significant difference in coronary flow. Therefore, the number of functional cardiac sarcolemmal KATP channels is a critical determinant of the rate of adaptation of myocardial membrane excitability, with implications for optimization of cardiac energy consumption and consequent cardioprotection under conditions of severe metabolic stress. 相似文献
98.
99.
Melero M Rubio-Guerri C Crespo JL Arbelo M Vela AI García-Párraga D Sierra E Domínguez L Sánchez-Vizcaíno JM 《Diseases of aquatic organisms》2011,97(2):167-170
An adult female bottlenose dolphin (Tursiops truncatus) stranded alive and subsequently died several minutes later on the Mediterranean coast of Spain on 14 July 2010. Clinical examination revealed foam through the blowhole and rales upon lung auscultation. On venipuncture, the blood was abnormally dense and dark. Hematological and biochemical abnormalities included dehydration, leukocytosis (48 600 leukocytes microl(-1)) characterized by neutrophilia (48 200 neutrophils microl(-1)), and elevated bilirubin (4.38 mg dl(-1)), alanine aminotransferase (382.3 U l(-1)), aspartate aminotransferase (1449.3 U l(-1)), lactate dehydrogenase (1631.3 U l(-1)), and creatine kinase (404.7 U l(-1)). The most relevant findings of the gross examination were rhomboid-shaped skin lesions, stable froth in the trachea, pulmonary congestion, abnormally thick and rough pleura with adhesions, edematous and congestive superficial cervical and tracheobronchial lymph nodes, red-tinged urine, and severe brain congestion. Histopathology of the kidney, lung, skin, and brain revealed multisystemic intravascular bacterial emboli. Samples of skin, brain, and lung were cultured on Columbia blood agar under both aerobic and anaerobic conditions, and pure and heavy bacterial cultures were obtained from skin and brain samples. The microorganism isolated was Gram-positive, catalase-negative, facultatively anaerobic, and rod-shaped. The isolates were identified as Erysipelothrix rhusiopathiae by the API Coryne biochemical system. Based on the gross and microscopic findings, a diagnosis of acute E. rhusiopathiae septicemia was made. To the best of our knowledge, this is the first report of E. rhusiopathiae septicemia in a free-ranging bottlenose dolphin. 相似文献
100.
Basilio D Jennings-Antipov LD Jakes KS Finkelstein A 《The Journal of general physiology》2011,137(4):343-356
Anthrax toxin consists of three proteins: lethal factor (LF), edema factor (EF), and protective antigen (PA). This last forms a heptameric channel, (PA63)7, in the host cell’s endosomal membrane, allowing the former two (which are enzymes) to be translocated into the cytosol. (PA63)7 incorporated into planar bilayer membranes forms a channel that translocates LF and EF, with the N terminus leading the way. The channel is mushroom-shaped with a cap containing the binding sites for EF and LF, and an ∼100 Å–long, 15 Å–wide stem. For proteins to pass through the stem they clearly must unfold, but is secondary structure preserved? To answer this question, we developed a method of trapping the polypeptide chain of a translocating protein within the channel and determined the minimum number of residues that could traverse it. We attached a biotin to the N terminus of LFN (the 263-residue N-terminal portion of LF) and a molecular stopper elsewhere. If the distance from the N terminus to the stopper was long enough to traverse the channel, streptavidin added to the trans side bound the N-terminal biotin, trapping the protein within the channel; if this distance was not long enough, streptavidin did not bind the N-terminal biotin and the protein was not trapped. The trapping rate was dependent on the driving force (voltage), the length of time it was applied, and the number of residues between the N terminus and the stopper. By varying the position of the stopper, we determined the minimum number of residues required to span the channel. We conclude that LFN adopts an extended-chain configuration as it translocates; i.e., the channel unfolds the secondary structure of the protein. We also show that the channel not only can translocate LFN in the normal direction but also can, at least partially, translocate LFN in the opposite direction. 相似文献