7 research outputs found
Association analysis of grain-setting rates in apical and basal spikelets in bread wheat (Triticum aestivum L.)
The rates of grain-setting in apical and basal spike lets in wheat directly affect the kernel number perspike(KNPS). Inthisstudy, 220 wheat lines from 18 Chinese provinces and five foreign countries were used as a natural population. Phenotypic an alysis showed difference singrain-setting rates between apical and basal spike lets. Thebroad-senseher it ability of grain-setting rate in apical spike lets(18.7–21.0%) washigher than that forbasal spike lets(9.4–16.4%). Significant correlations were found between KNPS and grain numbers in apical (R2 = 0.40– 0.45,P<0.01) andbasal (R2=0.41–0.56,P<0.01) spikelets. Seventy two of 106 SSR markers were associated with grain setting, 32 for apical spike lets, and 34 for basalspike lets. The SSR lociwe relocatedon 17chromosomes, except3A, 3D, 4A, and 7D, and explained 3.7–22.9% of the phenotypicvariance. Four markers, Xcfa2153-1A202, Xgwm186-5A118, Xgwm156-3B319,andXgwm537-7B210, showed the largest effects on grain numbers in apical and basal spikelets. Highgra innumbers inapical and basal spikelets were associated with elitealleles. Ningmai9, Ning0569, and Yangmai 18 with high grain-setting rate scarried large rnumbers off avorablealleles. Comparison of grain numbers in basal and apical spike lets of 35 Yangmai and Ningmai lines indicated that the Ningma ilines had better grain-settingrates(mean21.4) than the Yangmai lines(16.5)
Brain damages in ketamine addicts as revealed by magnetic resonance imaging
Ketamine, a known antagonist of N-methyl-D-aspartic (NMDA) glutamate receptors, had been used as an anesthetic particularly for pediatric or for cardiac patients. Unfortunately, ketamine has become an abusive drug in many parts of the world while chronic and prolonged usage led to damages of many organs including the brain. However, no studies on possible damages in the brains induced by chronic ketamine abuse have been documented in the human via neuroimaging. This paper described for the first time via employing magnetic resonance imaging (MRI) the changes in ketamine addicts of 0.5 to 12 years and illustrated the possible brain regions susceptible to ketamine abuse. Twenty-one ketamine addicts were recruited and the results showed that the lesions in the brains of ketamine addicts were located in many regions which appeared 2-4 years after ketamine addiction. Cortical atrophy was usually evident in the frontal, parietal or occipital cortices of addicts. Such study confirmed that many brain regions in the human were susceptible to chronic ketamine injury and presented a diffuse effect of ketamine on the brain which might differ from other central nervous system (CNS) drugs, such as cocaine, heroin and methamphetamine
Identification of WOX family genes in Selaginella kraussiana for studies on stem cells and regeneration in lycophytes
Plant stem cells give rise to all tissues and organs and also serve as the source for plant regeneration. The organization of plant stem cells has undergone a progressive change from simple to complex during the evolution of vascular plants. Most studies on plant stem cells have focused on model angiosperms, the most recently diverged branch of vascular plants. However, our knowledge of stem cell function in other vascular plants is limited. Lycophytes and euphyllophytes (ferns, gymnosperms, and angiosperms) are two existing branches of vascular plants that separated more than 400 million years ago. Lycophytes retain many of the features of early vascular plants. Based on genome and transcriptome data, we identified WUSCHEL-RELATED HOMEOBOX (WOX) genes in Selaginella kraussiana, a model lycophyte that is convenient for in vitro culture and observations of organ formation and regeneration. WOX genes are key players controlling stem cells in plants. Our results showed that the S. kraussiana genome encodes at least eight members of the WOX family, which represent an early stage of WOX family evolution. Identification of WOX genes in S. kraussiana could be a useful tool for molecular studies on the function of stem cells in lycophytes
Deletion of the small RNA chaperone protein Hfq down regulates genes related to virulence and confers protection against wild-type Brucella challenge in mice
Brucellosis is one of the most common zoonotic epidemics worldwide. Brucella, the etiological pathogen of brucellosis, has unique virulence characteristics, including the ability to survive within the host cell. Hfq is a bacterial chaperone protein that is involved in the survival of the pathogen under stress conditions. Moreover, hfq affects the expression of a large number of target genes. In the present study, we characterized the expression and regulatory patterns of the target genes of Hfq during brucellosis. The results revealed that hfq expression is highly induced in macrophages at the early infection stage and at the late stage of mouse infection. Several genes related to virulence, including omp25, omp31, vjbR, htrA, gntR, and dnaK, were found to be regulated by hfq during infection in BALB/c mice. Gene expression and cytokine secretion analysis revealed that an hfq-deletion mutant induced different cytokine profiles compared with that induced by 16M. Infection with the hfq-deletion mutant induced protective immune responses against 16M challenge. Together, these results suggest that hfq is induced during infection and its deletion results in significant attenuation which affects the host immune response caused by Brucella infection. By regulating genes related to virulence, hfq promotes the virulence of Brucella. The unique characteristics of the hfq-deletion mutant, including its decreased virulence and the ability to induce protective immune response upon infection, suggest that it represents an attractive candidate for the design of a live attenuated vaccine against Brucella
Genome-wide identification of non-coding RNAs interacted with microRNAs in soybean
A wide range of RNA species interacting with microRNAs (miRNAs) form a complex gene regulation network and play vital roles in diverse biological processes. In this study, we performed a genome-wide identification of endogenous target mimics (eTMs) for miRNAs and phased-siRNA-producing loci (PHAS) in soybean with a focus on those involved in lipid metabolism. The results showed that a large number of eTMs and PHAS genes could be found in soybean. Additionally, we found that lipid metabolism related genes were potentially regulated by 28 miRNAs, and nine of them were potentially further regulated by a number of eTMs with expression evidence. Thirty-three miRNAs were found to trigger production of phasiRNAs from 49 PHAS genes, which were able to target lipid metabolism related genes. Degradome data supported miRNA- and/or phasiRNA-mediated cleavage of genes involved in lipid metabolism. Most eTMs for miRNAs involved in lipid metabolism and phasiRNAs targeting lipid metabolism related genes showed a tissue-specific expression pattern. Our bioinformatical evidences suggested that lipid metabolism in soybean is potentially regulated by a complex non-coding network, including miRNAs, eTMs and phasiRNAs, and the results extended our knowledge on functions of non-coding RNAs
Comparative Analysis of Complete Chloroplast Genome Sequences of two tropical trees Machilus yunnanensis and Machilus balansae in the family Lauraceae
Machilus is a large (c. 100 spp.) genus of trees in the family Lauraceae, distributed in tropical and subtropical East Asia. Both molecular species identification and phylogenetic studies of this morphologically uniform genus have been constrained by insufficient variable sites among frequently-used biomarkers. To better understand the mutation patterns in the chloroplast genome of Machilus, the complete plastomes of two species were sequenced. The plastomes of M. yunnanensis and M. balansae were 152, 622 bp and 152, 721 bp respectively. Seven highly variable regions between the two Machilus species and three of them between Machilus and Cinnamomum were identified and 297 mutation events, including one micro-inversion in the ccsA-ndhD region, 65 indels, and 231 substitutions, were accurately located. Thirty-six microsatellite sites were found for use in species identification and 95 single-nucleotide changes were identified in gene coding regions
A compendium of preparation and application of stem cells in Parkinson’s Disease: current status and future prospects
Parkinson’s Disease (PD) is a progressively neurodegenerative disorder, implicitly characterized by a stepwise loss of dopaminergic (DA) neurons in the substantia nigra pars compacta (SNpc) and explicitly marked by bradykinesia, rigidity, resting tremor and postural instability. Currently, therapeutic approaches available are mainly palliative strategies, including L-3,4-dihydroxy-phenylalanine (L-DOPA) replacement therapy, DA receptor agonist and deep brain stimulation (DBS) procedures. As the disease proceeds, however, the pharmacotherapeutic efficacy is inevitably worn off, worse still, implicated by side effects of motor response oscillations as well as L-DOPA induced dyskinesia (LID). Therefore, the frustrating status above has propeled the shift to cell replacement therapy (CRT), a promising restorative therapy intending to secure a long-lasting relief of patients’ symptoms. By far, stem cell lines of multifarious origins have been established, which can be further categorized into embryonic stem cells (ESCs), neural stem cells (NSCs), induced neural stem cells (iNSCs), mesenchymal stem cells (MSCs) and induced pluripotent stem cells (iPSCs). In this review, we intend to present a compendium of preparation and application of multifarious stem cells, especially in relation to PD research and therapy. In addition, the current status, potential challenges and future prospects for practical CRT in PD patients will be elaborated as well