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1.
Androgen induces production of male effect pheromone in female goats   总被引：1，自引：0，他引：1  
Previously we showed that the primer pheromone responsible for the "male effect" was produced in specific skin regions of castrated male goats by androgen treatments. In the present study, we examined whether androgen can also induce production of the male effect pheromone in female goats. Capsules containing dihydrotestosterone (DHT) or testosterone (T) were subcutaneously implanted into six ovariectomized (OVX) goats for 28 days. Small skin samples were collected from the head and rump regions, and the pheromone activity of their ether extracts was examined using a bioassay that monitors the electrophysiological manifestation of the hypothalamic gonadotropin-releasing hormone pulse generator as multiple-unit activity. Behaviors of OVX goats towards ovary-intact estrous goats were also examined before and at the end of DHT or T treatment. Before androgen treatment, neither the head nor rump skin samples in OVX goats showed pheromone activity. DHT treatment induced pheromone activity in the head skin sample of six OVX goats and in the rump skin sample of two OVX goats. Similar results were obtained by T treatment. In addition, OVX goats treated with T showed masculine-type sexual behaviors such as courtship and mounting behaviors towards the estrous goats. These results demonstrate that androgen is capable of inducing primer pheromone activity in the female and suggest that the synthesis pathway of the male effect pheromone exists in both sexes in the goat.  相似文献   
2.
To act as guides in the RNA interference (RNAi) pathway, small interfering RNAs (siRNAs) must be unwound into their component strands, then assembled with proteins to form the RNA-induced silencing complex (RISC), which catalyzes target messenger RNA cleavage. Thermodynamic differences in the base-pairing stabilities of the 5' ends of the two approximately 21-nucleotide siRNA strands determine which siRNA strand is assembled into the RISC. We show that in Drosophila, the orientation of the Dicer-2/R2D2 protein heterodimer on the siRNA duplex determines which siRNA strand associates with the core RISC protein Argonaute 2. R2D2 binds the siRNA end with the greatest double-stranded character, thereby orienting the heterodimer on the siRNA duplex. Strong R2D2 binding requires a 5'-phosphate on the siRNA strand that is excluded from the RISC. Thus, R2D2 is both a protein sensor for siRNA thermodynamic asymmetry and a licensing factor for entry of authentic siRNAs into the RNAi pathway.  相似文献   
3.
Xie  Weimin  Wang  Qunhui  Yao  Jie  Ma  Hongzhi  Ohsumi  Yukihide  Ogawa  Hiroaki I. 《Water, air, and soil pollution》2004,159(1):313-324
The adsorption of a fixed bed filled with bone char was investigated in terms of its efficiency and capacity by determining operational conditions for the purpose of further reduction of organic matter and removal of phosphorus using a continuous flow of real secondary effluent. Simultaneous removals of phosphorus and chemical oxygen demand (COD) were sufficiently achieved by this fixed-bed method. Stable performance was maintained even at a linear flow velocity (abbreviated as LV) of 1.5 m h–1. Appropriate backwashing and regeneration were required to operate the system continuously for a long period of time. During the regeneration, the use of treated water including Ca2+ ion was so effective that phosphorus removal efficiency increased from about 50 to 80%, and afterwards maintained over 65%, until inflow water of the volume up to 150 times as large as the volume of bone char had passed through. Even when the inflow water of the volume rose up to 200 times, the phosphorus removal efficiency could be maintained over 50%. During this operation, the adsorptions of phosphorus and COD onto the bone char surface were observed to be over 6.7 and 35 gL–1, respectively.  相似文献   
4.
Excitatory amino acid transporters (EAATs) are important for terminating glutamatergic neurotransmission and protect central nervous system (CNS) neurons from glutamatergic excitotoxicity. We selected these genes as targets that may relate to canine behavioral traits. After screening four EAAT genes (glutamate transporter-1; GLT-1, excitatory amino acid transporter 4; EAAT4, excitatory amino acid carrier; EAAC1, glutamate/aspartate transporter; GLAST) for single nucleotide polymorphisms (SNPs), we identified two silent SNPs (C129T and T471C) in the GLT-1 gene. We genotyped 193 dogs of 5 breeds and found significant variation among breeds in these two SNPs in GLT-1. The C129T polymorphism was not observed in Malteses and Miniature Schnauzers. These results suggest that polymorphisms in the GLT-1 gene may be useful markers for examining how the genetic background relates to the behavioral traits of dogs.  相似文献   
5.
Laboratory experiments were conducted to investigate (1) the effects of the addition of rice (Oryza sativa. L.) bran to paddy soil on the germination of Monochoria vaginalis (Burm. f.) Kunth, and (2) the relationship between the electric conductivity (EC) of the soil solution and germination. Soil samples were collected at 4 sites in Japan. After flooded soils with rice bran had been incubated for 7?d at 30°C, the soil solution was collected using a porous cup and the EC of the soil solution was measured. The amounts of rice bran added to the soil were 0%, 0.3%, 0.6% and 0.9% (weight(w)/w). In the soil solution obtained, seeds of M. vaginalis were incubated for 3?d at 30°C, and the germination percentage was then analyzed. The addition of rice bran suppressed germination, and the degree of suppression increased with increasing content of rice bran. Although the same amount of rice bran was applied to each soil, the degree of growth suppression by rice bran as well as the EC of the soil solution differed among the soils. In each soil, there was a positive correlation between the amount of rice bran and EC, and the degree of growth suppression significantly increased with an increase in EC. When EC was higher than 150?mS?m?1, seeds of M. vaginalis hardly germinated. There was no significant correlation between the oxidation-reduction potential (Eh) of soil and seed germination, suggesting that EC is a more reliable and convenient indicator than Eh for evaluating the relationship between the addition of organic material and seed germination. In conclusion, the addition of rice bran to soil increases the EC of the soil solution, and EC is one of the factors that suppress the germination of M. vaginalis. The suppressive effect of rice bran on germination is different among soils. This fact is attributed to the difference in EC due to the addition of rice bran. Thus, it is expected that EC can be used as an indicator for determining how much rice bran to add.  相似文献   
6.
Monoamine oxidase B catalytically oxidizes biogenic amines such as phenylethylamine and dopamine, and its activity is presumed to be related to particular behavioral traits. In this study, we first identified a single nucleotide polymorphism (T199C) located on the putative third exon of the canine monoamine oxidase B gene, which causes an amino acid substitution from cysteine to arginine. We then examined the allelic frequencies in five dog breeds (Golden Retriever, Labrador Retriever, Maltese, Miniature Schnauzer, and Shiba) and found significant variation among them. The present results suggest that analysis of the monoamine oxidase B polymorphism could be a useful means of elucidating the genetic background of breed-specific behavioral characteristics in dogs.  相似文献   
7.
The role of monoamine oxidase has been shown to be related to some behavioral changes including aggression and cognitive dysfunction. In order to demonstrate the basic expression patterns of monoamine oxidase in the canine brain, we determined the full-length nucleotide sequences of cDNA for canine monoamine oxidase type A (MAOA) and type B (MAOB) genes that were isolated from the canine brain cDNA library. Oligonucleotide primers for PCR were constructed based on the conserved sequences reported thus far for other mammalian species. The nucleotide sequences had open reading frames of 1584 and 1563 bp for MAOA and MAOB, respectively. Both of these genes showed relatively high homology with other species in both nucleotide (> 81%) and deduced amino acid (> 85%) sequences. In Northern blot analyses MAOA mRNA was expressed broadly in various parts of the canine brain, whereas MAOB mRNA was found only in specific brain regions, such as the hypothalamus, hippocampus, brain stem and olfactory bulb. These results suggest that MAOA and MAOB mRNAs have subtype-specific expression patterns in the canine brain.  相似文献   
8.
Interest in the production of lactic acid (LA) is increasing inrelation to its applications in the synthesis of biodegradablepolymer materials. Before kitchen waste is used as substrates inLA fermentation, it must be stored for some days in the wastecollection system. This study examined the effects of pHadjustment including initial pH before the storage in terms of thekind and the amount of added acid on preservation of the waste. The optical purity of LA generated during the storage was alsoanalyzed. It was found that antibacterial activity andsuppression ability to D-lactic acid (D-LA) were stronger in theorder: acetic acid > L-lactic acid (L-LA) > hydrochloric acid ≈ nitric acid. The optimum condition of waste storage was found to be adjusting initial pH to 3.4 by adding acetic acid. It can be expected that preservation of kitchen waste can be realized by inhibiting the growth of putrefactive bacteria, and higher optical purity of L-LA was obtained by adding weak acid to the waste.  相似文献   
9.
Dopamine and noradrenaline are catecholamine neurotransmitters that are produced by biosynthetic enzymes such as tyrosine hydroxylase (TH) and dopamine beta -hydroxylase (DBH). As a first step to elucidate the genetic background of canine behavioral traits, we selected these genes as targets and sequenced these canine genes, and found that both were highly homologous with those of human beings. Then brain cDNAs derived from ten unrelated Beagles were used to search for polymorphisms in these genes. Four single nucleotide polymorphisms (SNPs) (C97T, G168A, G180A and C264T), one of which (C97T) will cause amino acid substitution in the TH gene, and two SNPs (C789A and A1819G), both of which will cause amino acid substitutions in the DBH gene were identified. The allelic frequencies among five dog breeds (47 Golden Retrievers, 41 Labrador Retrievers, 40 Malteses, 26 Miniature Schnauzers, and 39 Shibas) were examined and found to have significant variation between them with regards to all these SNPs, except for C97T in the TH gene and A1819G in the DBH gene. The polymorphisms of C97T and A1819G were found only in the Shiba. The present results suggest that the polymorphisms of the genes encoding catecholamine biosynthetic enzymes may become important markers for examining the genetic background of behavioral characteristics in dogs.  相似文献   
10.
The 'male effect' is a well-known phenomenon in female sheep and goats, whereby pheromone-induced activation of reproductive function occurs. In a previous study, we showed that the genes for elongation of long-chain fatty acids family member 5 (ELOVL5) and stearoyl-CoA desaturase 1 (SCD1) increased their expression significantly, concomitant with induction of pheromone synthesis. Therefore, these genes were considered to be prime candidate genes for pheromone synthesis. In the present study, we performed in situ hybridization to investigate where these two genes are expressed in goat skin. Strong positive signals were detected for both genes in the head skin of the male goat, which is the main site of pheromone production, and were mainly in the basal layer of the sebaceous gland cells, with the remaining cells showing negligible signals. None of the cells in the rump skin of the male goat or the head skin of the orchidectomized goat, neither of which produce pheromone, exhibited strong positive signals. The present study demonstrates that expression of these two candidate genes for pheromone synthesis is primarily localized in the sebaceous glands of the pheromone-producing skin region.  相似文献   
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