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排序方式: 共有765条查询结果,搜索用时 109 毫秒
681.
682.
Mei‐Lyn Ong Ta A. Tuan Joann Poh Ai L. Teh Li Chen Hong Pan Julia L. MacIsaac Michael S. Kobor Yap S. Chong Kenneth Kwek Seang M. Saw Keith M. Godfrey Peter D. Gluckman Marielle V. Fortier Neerja Karnani Michael J. Meaney Anqi Qiu Joanna D. Holbrook 《Genes, Brain & Behavior》2019,18(7)
The amygdala and hippocampus undergo rapid development in early life. The relative contribution of genetic and environmental factors to the establishment of their developmental trajectories has yet to be examined. We performed imaging on neonates and examined how the observed variation in volume and microstructure of the amygdala and hippocampus varied by genotype, and compared with prenatal maternal mental health and socioeconomic status. Gene × Environment models outcompeted models containing genotype or environment only to best explain the majority of measures but some, especially of the amygdaloid microstructure, were best explained by genotype only. Models including DNA methylation measured in the neonate umbilical cords outcompeted the Gene and Gene × Environment models for the majority of amygdaloid measures and minority of hippocampal measures. This study identified brain region‐specific gene networks associated with individual differences in fetal brain development. In particular, genetic and epigenetic variation within CUX1 was highlighted. 相似文献
683.
Salman Abdo Al-Shami Che Salmah Md Rawi Suhaila Abdul Hamid Nurul Huda Abdul Mariam Zhafarina Rusli Wan Nur Asiah Wan Mohd Adnan Nur Adibah Mohd Ishadi Mohd Shafiq Zakeyuddin Sanya Abdulkareem Al-Qormuti Khalid A. Al-Mutairi Yap Chee Kong 《农业工程》2021,41(1):50-56
The loss of aquatic biodiversity in tropical streams of SE Asia is evident due to increasing anthropogenic activities. Therefore, there is a necessity for immediate and feasible conservation plans. Effective conservation planning depends on successful application of surrogate groups. However, progress of this approach is hindered by the paucity of relevant reports based on cross-taxon congruence analysis. In this study, we investigated congruence patterns among aquatic groups (Plecoptera, Trichoptera, Ephemeroptera, Odonata and fish) in six rivers located in the Kerian River Basin (KRB), Malaysia. Species richness was significantly correlated among aquatic groups (except for Ephemeroptera and Trichoptera where r = 0.040 and P = 0.202). The strongest relationship in species richness was reported between Ephemeroptera and Plecoptera. The Mantel's r coefficient of similarity matrices (based on the Bray-Curtis distance measure) showed a positive correlation between the matrices of Ephemeroptera-Trichoptera and Plecoptera-Trichoptera. However, a negative relationship was reported between Odonata-fish matrices. The relationships between average Trichoptera-Odonata distance to the centroid (i.e. beta diversity) among the aquatic groups were also investigated. The strongest relationship in the average to the centroids was reported between Ephemeroptera and Odonata (R2 = 0.424, P < 0.05). However, the weakest relationship was reported between Trichoptera and fish with R2 value of 0.024. It is concluded that richness of Plecoptera, Odonata and fish showed correlations patterns, and these can be used as surrogates for each other with some restrictions. 相似文献
684.
Hui-Yeng Y Yap Yit-Heng Chooi Mohd Firdaus-Raih Shin-Yee Fung Szu-Ting Ng Chon-Seng Tan Nget-Hong Tan 《BMC genomics》2014,15(1)
Background
The sclerotium of Lignosus rhinocerotis (Cooke) Ryvarden or Tiger milk mushroom (Polyporales, Basidiomycota) is a valuable folk medicine for indigenous peoples in Southeast Asia. Despite the increasing interest in this ethnobotanical mushroom, very little is known about the molecular and genetic basis of its medicinal and nutraceutical properties.Results
The de novo assembled 34.3 Mb L. rhinocerotis genome encodes 10,742 putative genes with 84.30% of them having detectable sequence similarities to others available in public databases. Phylogenetic analysis revealed a close evolutionary relationship of L. rhinocerotis to Ganoderma lucidum, Dichomitus squalens, and Trametes versicolor in the core polyporoid clade. The L. rhinocerotis genome encodes a repertoire of enzymes engaged in carbohydrate and glycoconjugate metabolism, along with cytochrome P450s, putative bioactive proteins (lectins and fungal immunomodulatory proteins) and laccases. Other genes annotated include those encoding key enzymes for secondary metabolite biosynthesis, including those from polyketide, nonribosomal peptide, and triterpenoid pathways. Among them, the L. rhinocerotis genome is particularly enriched with sesquiterpenoid biosynthesis genes.Conclusions
The genome content of L. rhinocerotis provides insights into the genetic basis of its reported medicinal properties as well as serving as a platform to further characterize putative bioactive proteins and secondary metabolite pathway enzymes and as a reference for comparative genomics of polyporoid fungi.Electronic supplementary material
The online version of this article (doi:10.1186/1471-2164-15-635) contains supplementary material, which is available to authorized users. 相似文献685.
Lin Zhang Ronghong Tang Shu Bai Natalie K. Connors Linda H. L. Lua Yap P. Chuan Anton P. J. Middelberg Yan Sun 《PloS one》2014,9(9)
The success of recombinant virus-like particles (VLPs) for human papillomavirus and hepatitis B demonstrates the potential of VLPs as safe and efficacious vaccines. With new modular designs emerging, the effects of antigen module insertion on the self-assembly and structural integrity of VLPs should be clarified so as to better enabling improved design. Previous work has revealed insights into the molecular energetics of a VLP subunit, capsomere, comparing energetics within various solution conditions known to drive or inhibit self-assembly. In the present study, molecular dynamics (MD) simulations coupled with the molecular mechanics-Poisson-Boltzmann surface area (MM-PBSA) method were performed to examine the molecular interactions and energetics in a modular capsomere of a murine polyomavirus (MPV) VLP designed to protect against influenza. Insertion of an influenza antigenic module is found to lower the binding energy within the capsomere, and a more active state is observed in Assembly Buffer as compared with that in Stabilization Buffer, which has been experimentally validated through measurements using differential scanning calorimetry. Further in-depth analysis based on free-energy decomposition indicates that destabilized binding can be attributed to electrostatic interaction induced by the chosen antigen module. These results provide molecular insights into the conformational stability of capsomeres and their abilities to be exploited for antigen presentation, and are expected to be beneficial for the biomolecular engineering of VLP vaccines. 相似文献
686.
687.
Ena/VASP proteins can regulate distinct modes of actin organization at cadherin-adhesive contacts 总被引:1,自引:0,他引:1 下载免费PDF全文
Scott JA Shewan AM den Elzen NR Loureiro JJ Gertler FB Yap AS 《Molecular biology of the cell》2006,17(3):1085-1095
Functional interactions between classical cadherins and the actin cytoskeleton involve diverse actin activities, including filament nucleation, cross-linking, and bundling. In this report, we explored the capacity of Ena/VASP proteins to regulate the actin cytoskeleton at cadherin-adhesive contacts. We extended the observation that Ena/vasodilator-stimulated phosphoprotein (VASP) proteins localize at cell-cell contacts to demonstrate that E-cadherin homophilic ligation is sufficient to recruit Mena to adhesion sites. Ena/VASP activity was necessary both for F-actin accumulation and assembly at cell-cell contacts. Moreover, we identified two distinct pools of Mena within individual homophilic adhesions that cells made when they adhered to cadherin-coated substrata. These Mena pools localized with Arp2/3-driven cellular protrusions as well as at the tips of cadherin-based actin bundles. Importantly, Ena/VASP activity was necessary for both modes of actin activity to be expressed. Moreover, selective depletion of Ena/VASP proteins from the tips of cadherin-based bundles perturbed the bundles without affecting the protrusive F-actin pool. We propose that Ena/VASP proteins may serve as higher order regulators of the cytoskeleton at cadherin contacts through their ability to modulate distinct modes of actin organization at those contacts. 相似文献
688.
Shell morphological characters and allozyme electrophoresis were used to study the relationships among six geographical populations
of land snails collected from Peninsular Malaysia. Allozyme electrophoresis was used to study the genetic variations to complement
the morphological features studied that included shell lengths, numbers of whorls and shell colour. Ten loci coding for six
enzymes (MDH, LAP, ALP, PGM, G6P DH, and EST) could be reliably scored in samples from the six populations studied. The dendrogram showed two major clusters with one
cluster comprising Subulinidae populations from Perak, Selangor, Johor, Terengganu, and Pahang while the other cluster included
only the Streptaxidae Huttonella bicolor (red) population. The Subulinidae populations were grouped into two subclusters: one subcluster included the Subulina sp. populations from Perak, Selangor, and Johor, while the other subcluster included the Opeas sp. populations from Terengganu and Pahang. Morphological features can identify the different families ant therefore they
can complement the allozyme genetic studies on the land snail populations. Like other reports in the literature, our results
also underline the importance of a genetic approach in conjunction with a morphological approach, for discriminating land
snail species. The present results suggest that small land snails, which were similar in colour but different in sizes, were
not of the same family/genus.
The text was submitted by the authors in English. 相似文献
689.
690.
The present investigation was carried out in an attempt to study the phylogenetic analysis of different breeds of domestic chickens in Peninsular Malaysia inferred from partial cytochrome b gene information and random amplified polymorphic DNA (RAPD) markers. Phylogenetic analysis using both neighbor-joining (NJ) and maximum parsimony (MP) methods produced three clusters that encompassed Type-I village chickens, the red jungle fowl subspecies and the Japanese Chunky broilers. The phylogenetic analysis also revealed that majority of the Malaysian commercial chickens were randomly assembled with the Type-II village chickens. In RAPD assay, phylogenetic analysis using neighbor-joining produced six clusters that were completely distinguished based on the locality of chickens. High levels of genetic variations were observed among the village chickens, the commercial broilers, and between the commercial broilers and layer chickens. In this study, it was found that Type-I village chickens could be distinguished from the commercial chickens and Type-II village chickens at the position of the 27th nucleotide of the 351?bp cytochrome b gene. This study also revealed that RAPD markers were unable to differentiate the type of chickens, but it showed the effectiveness of RAPD in evaluating the genetic variation and the genetic relationships between chicken lines and populations. 相似文献