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991.
Association analysis between feed efficiency studies and expression of hypothalamic neuropeptide genes in laying ducks 下载免费PDF全文
Residual feed intake (RFI) is now considered a more reasonable metric to evaluate animal feed efficiency. In this study, the correlation between RFI and other feed efficiency traits was investigated and gene expression within the hypothalamus was determined in low RFI (LRFI) and high RFI (HRFI) ducks. Further, several hypothalamic neuropeptide genes were measured using quantitative real‐time PCR. The mean feed intake value was 160 g/day, whereas the egg mass laid (EML) and body weight were approximately 62.4 g/day and 1.46 kg respectively. Estimates for heritability of RFI, feed conversion ratio (FCR) and feed intake were 0.26, 0.18 and 0.23 respectively. RFI is phenotypically positively correlated with feed intake and FCR (P < 0.01). The expression of neuropeptide Y (NPY) and neuropeptide Y receptor Y5 (NPY5R) mRNA was higher in HRFI ducks compared with LRFI ducks (P < 0.05), whereas that of proopiomelanocortin (POMC), melanocortin 4 receptor (MC4R) and cholecystokinin (CCK) was lower (P < 0.05). The mRNA expression of gonadotropin‐releasing hormone 1 (luteinizing‐releasing hormone) (GNRH1) and prolactin receptor (PRLR) was unchanged between LRFI and HRFI ducks. The results indicate that selection for LRFI could reduce feed intake without significant changes in EML, whereas selection on FCR will increase EML. 相似文献
992.
993.
Lihong Chen Wei Hu Shenglong Tan Min Wang Zhanbing Ma Shiyi Zhou Xiaomin Deng Yang Zhang Chao Huang Guangxiao Yang Guangyuan He 《PloS one》2012,7(10)
MAPK cascades are universal signal transduction modules and play important roles in plant growth, development and in response to a variety of biotic and abiotic stresses. Although MAPKs and MAPKKs have been systematically investigated in several plant species including Arabidopsis, rice and poplar, no systematic analysis has been conducted in the emerging monocot model plant Brachypodium distachyon. In the present study, a total of 16 MAPK genes and 12 MAPKK genes were identified from B. distachyon. An analysis of the genomic evolution showed that both tandem and segment duplications contributed significantly to the expansion of MAPK and MAPKK families. Evolutionary relationships within subfamilies were supported by exon-intron organizations and the architectures of conserved protein motifs. Synteny analysis between B. distachyon and the other two plant species of rice and Arabidopsis showed that only one homolog of B. distachyon MAPKs was found in the corresponding syntenic blocks of Arabidopsis, while 13 homologs of B. distachyon MAPKs and MAPKKs were found in that of rice, which was consistent with the speciation process of the three species. In addition, several interactive protein pairs between the two families in B. distachyon were found through yeast two hybrid assay, whereas their orthologs of a pair in Arabidopsis and other plant species were not found to interact with each other. Finally, expression studies of closely related family members among B. distachyon, Arabidopsis and rice showed that even recently duplicated representatives may fulfill different functions and be involved in different signal pathways. Taken together, our data would provide a foundation for evolutionary and functional characterization of MAPK and MAPKK gene families in B. distachyon and other plant species to unravel their biological roles. 相似文献
994.
995.
Sargassum is a cosmopolitan brown algal genus spanning the three ocean basins of the Atlantic, Pacific and Indian Oceans, inhabiting temperate, subtropical and tropical habitats. Sargassum has been postulated to have originated in the Oligocene epoch approximately 30 mya according to a broad phylogenetic analysis of brown macroalgae, but its diversification to become one of the most widespread and speciose macroalgal genera remains unclear. Here, we present a Bayesian molecular clock study, which analyzed data from the order Fucales of the brown algal crown radiation (BACR) group to reconstruct a time-calibrated phylogeny of the Sargassum clade. Our phylogeny included a total of 120 taxa with 99 Sargassum species sampled for three molecular markers – ITS-2, cox3 and rbcLS – calibrated with an unambiguous Sargassaceae fossil from between the lower and middle Miocene. The analysis revealed a much later origin of Sargassum than expected at about 6.7 mya, with the genus diversifying since approximately 4.3 mya. Current geographic distributions of Sargassum species were then analyzed in conjunction with the time-calibrated phylogeny using the dispersal-extinction-cladogenesis (DEC) model to estimate ancestral ranges of clades in the genus. Results strongly support origination of Sargassum in the Central Indo-Pacific (CIP) region with subsequent independent dispersal events into other marine realms. The longer history of diversification in the ancestral CIP range could explain the much greater diversity there relative to other marine areas today. Analyses of these dynamic processes, when fine-tuned to a higher spatial resolution, enable the identification of evolutionary hotspots and provide insights into long-term dispersal patterns. 相似文献
996.
本文报导五加科一新属,人参本属Chengiopanax Shang et J.Y.Huang,新组合2种,即华人参木Ch.fargesii(Franch.)Shang et J.Y.Hung及人参木Ch.sciadophylloides(Franch.et Sav.)Shang et J.Y.Huang。 相似文献
997.
Li J Zhao GZ Huang HY Qin S Zhu WY Zhao LX Xu LH Zhang S Li WJ Strobel G 《Antonie van Leeuwenhoek》2012,101(3):515-527
Endophytic actinobacteria isolated from Artemisia annua were characterized and evaluated for their bioactivities. A total of 228 isolates representing at least 19 different genera
of actinobacteria were obtained and several of them seemed to be novel taxa. An evaluation of antimicrobial activity showed
that more isolates possessed activity towards plant pathogens than activity against other pathogenic bacteria or yeasts. High
frequencies of PCR amplification were obtained for type I polyketide synthases (PKS-I, 21.1%), type II polyketide synthases
(PKS-II, 45.2%) and nonribosomal peptide synthetases (NRPS, 32.5%). The results of herbicidal activity screening indicated
that 19 out of 117 samples of fermentation broths completely inhibited the germination of Echinochloa crusgalli. This study indicated that endophytic actinobacteria associated with A. annua are abundant and have potentially beneficial and diverse bioactivities which should be pursued for their biotechnical promise. 相似文献
998.
999.
1000.
Li Q Huang XJ He W Ding J Jia JT Fu G Wang HX Guo LJ 《Cellular and molecular neurobiology》2009,29(2):169-180
We previously reported that inhibition of Rho-kinase (ROCK) by hydroxyl fasudil improves cognitive deficit and neuronal damage
in rats with chronic cerebral ischemia (Huang et al., Cell Mol Neurobiol 28:757–768, 2008). In this study, fasudil mesylate
(FM) was investigated for its neuroprotective potential in rats with ischemia following middle cerebral artery occlusion (MCAO)
and reperfusion. The effect of fasudil mesylate was also studied in rat brain cortical and hippocampal slices treated with
oxygen-glucose deprivation (OGD) injury. Gross anatomy showed that cerebral infarct size, measured with 2,3,5-triphenyltetrazolium
chloride (TTC) staining, was significantly smaller in the FM-treated than in the non-FM-treated ischemic rats. In the brain
regions vulnerable to ischemia of ischemic rats, fasudil mesylate was also found to significantly restore the enzyme protein
expression level of endothelial nitric oxide synthase (eNOS), which was decreased in ischemia. However, it remarkably reduced
the protein synthesis of inducible nitric oxide synthase (iNOS) that was induced by ischemia and reperfusion. In rat brain
slices treated with OGD injury, fasudil mesylate increased the neuronal cell viability by 40% for cortex and by 61% for hippocampus,
respectively. Finally, in the presence of OGD and fasudil mesylate, superoxide dismutase (SOD) activity was increased by 50%
for cortex and by 58% for hippocampus, compared to OGD only group. In conclusion, our in vivo study showed that fasudil mesylate
not only decreased neurological deficit but also reduced cerebral infarct size, possibly and at least partially by augmenting
eNOS protein expression and inhibiting iNOS protein expression after ischemia-reperfusion.
Xian-Ju Huang contributed equally to this article. 相似文献