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1.
Cashmere is regarded as a specialty and luxury fiber due to its scarcity and high economic value. For fiber quality assessment, it is technically very challenging to distinguish and quantify the cashmere fiber from yak or wool fibers because of their highly similar physical appearance and substantial protein sequence homology. To address this issue, we propose a workflow combining untargeted and targeted proteomics strategies for selecting, verifying and quantifying biomarkers for cashmere textile authentication. Untargeted proteomic surveys were first applied to identify 174, 157, and 156 proteins from cashmere, wool and yak fibers, respectively. After marker selection at different levels, peptides turned out to afford much higher selectivity than proteins for fiber species discrimination. Subsequently, parallel reaction monitoring (PRM) methods were developed for ten selected peptide markers. The PRM-based targeted analysis of peptide markers enabled accurate determination of fiber species and cashmere percentages in different fiber mixtures. Furthermore, collective use of these peptide makers allowed us to discriminate and quantify cashmere fibers in commercial finished fabrics that have undergone heavy chemical treatments. Cashmere proportion measurement in fabric samples using our proteomic approach was in good agreement with results from traditional light microscopy, yet our method can be more readily standardized to become an objective and robust assay for assessing authenticity of fibers and textiles. We anticipate that the proteomic strategies presented in our study could be further implicated in discovery of quality trait markers for other products containing highly homologous proteomes.  相似文献   
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为探究球毛壳ND35微生物菌剂对楸树幼苗生长及土壤肥力的作用机制,本研究楸树幼苗为研究对象,采用室内盆栽试验,设计0(CK),10(T1),15(T2),20(T3)4种微生物菌剂施用量,测定幼苗生长情况、土壤微生物组成结构、土壤酶和土壤养分等特征。研究结果如下:(1)球毛壳ND35微生物菌剂可显著促进楸树幼苗的生长,株高、地径、地上及地下生物量显著提高(P<0.05),T2处理下促生效果最好。(2)施用球毛壳ND35微生物菌剂可显著提高土壤中有机质、硝态氮、铵态氮含量及脲酶、磷酸酶、蔗糖酶活性(P<0.05)。(3)球毛壳ND35微生物菌剂可显著影响土壤细菌群落组成,提高细菌群落的丰富度和多样性,使土壤中β-变形菌纲(Betaproteobacteria)、γ-变形菌纲(Gammaproteobacteria)的相对丰度显著下降,α-变形菌纲(Alphaproteobacteria)、δ-变形菌纲(Deltaproteobacteria)的相对丰度呈显著提高,可使土壤中鞘氨醇单胞菌属(Sphingomonas)的相对丰度显著提高21.88%-103.56%(P<0.05),芽孢杆菌属(Bacillus)的相对丰度提高66.28%-65.97%(P<0.05),酸杆菌属(Acidibacter)的相对丰度提高12.76%-38.06%。(4)冗余分析(RDA)结果表明,土壤硝态氮、铵态氮、有机质是影响土壤细菌群落分布和多样性的重要环境因子,土壤细菌群落结构的改变会显著影响土壤脲酶、蔗糖酶、碱性磷酸酶的活性。因此,施用球毛壳ND35微生物菌剂可通过影响植物根际土壤的化学性质及生物性质,促进楸树幼苗的生长。这一研究结果为楸树繁育提供了新的指导方向,亦为将其用于困难立地及退化生态系统植被恢复提供基础理论指导。  相似文献   
3.
During development, animals usually undergo a rapid growth phase followed by a homeostatic stage when growth has ceased. The increase in cell size and number during the growth phase requires a large amount of lipids; while in the static state, excess lipids are usually stored in adipose tissues in preparation for nutrient-limited conditions. How cells coordinate growth and fat storage is not fully understood. Through a genetic screen we identified Drosophila melanogaster CDP-diacylglycerol synthetase (CDS/CdsA), which diverts phosphatidic acid from triacylglycerol synthesis to phosphatidylinositol (PI) synthesis and coordinates cell growth and fat storage. Loss of CdsA function causes significant accumulation of neutral lipids in many tissues along with reduced cell/organ size. These phenotypes can be traced back to reduced PI levels and, subsequently, low insulin pathway activity. Overexpressing CdsA rescues the fat storage and cell growth phenotypes of insulin pathway mutants, suggesting that CdsA coordinates cell/tissue growth and lipid storage through the insulin pathway. We also revealed that a DAG-to-PE route mediated by the choline/ethanolamine phosphotransferase Bbc may contribute to the growth of fat cells in CdsA RNAi.  相似文献   
4.
We have reported nine distinct karyotypes for Aotus, of four pelagic phenotypes, and suggest that this single species has undergone extensive subspeciation. We reconstruct the mechanism of chromosomal evolution and propose a hypothesis about the events of subspeciation in Aotus. We speculate that isolated groups of ancestral individuals living in several confined areas have separately accumulated a fusion or inversion pair as a result of inbreeding. A subsequent reassociation of descendants from these individuals led to the formation of offspring with mixtures of fusion or inversion pairs in their complements. They, in turn, radiated into different ecological niches accompanied by adaptive genetic changes and eventually gave rise to the present forms of Aotus distinguishable by their karyotypes, but not easily recognizable by ordinary taxonomic criteria.  相似文献   
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Genetic transformation is one of the key steps in the molecular breeding of chrysanthemum, which relies on an optimal regeneration and transformation system. However, the regeneration system of different chrysanthemum cultivars varies, and the regeneration time of most cultivars is long. To screen cultivars with highly efficient regeneration, leaves and shoot tip thin cell layers (tTCL) from eight chrysanthemum cultivars with different flower colors and flower types were cultured on Murashige and Skoog media (MS) supplemented with 1.0–5.0 mg L−1 6-benzylaminopurine (6-BA) and 0.1–1.0 mg L−1 α-naphthaleneacetic (NAA). The results showed that the most efficient regeneration media were MS + 6-BA 1.0 mg L−1 + NAA 0.5 mg L−1 for leaf explants and MS + 6-BA 5.0 mg L−1 + NAA 0.1 mg L−1 for tTCL explants. Subsequently, another 13 chrysanthemum cultivars were screened by using the media, and finally, three cultivars with high regeneration efficiency were obtained from 21 cultivars. Among these, C1 had the highest regeneration efficiency: the regeneration rate of leaf explants reached 80.0% after 42 days of culture, and the regeneration rate of tTCL explants reached 100% after 31 days of culture. Furthermore, we also established the transformation system for C1 as follows: preculturing for one day, infecting with Agrobacterium suspension (OD600 = 0.6) for 10 min, and cultivating in the regeneration medium with 350 mg L−1 carbenicillin and 10 mg L−1 kanamycin, thus ultimately achieving a transformation rate of 4.0%. In this study, a new chrysanthemum cultivar with an efficient regeneration and transformation system was screened, which is beneficial to enrich the flower color of chrysanthemum transgenic plant recipients and to the functional research of flower color or type-related genes.  相似文献   
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