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61.
62.
Bao Yang Jianwu Li Jiayu Yan Ke Zhang Zhewen Ouyang Yefei Lu Huili Wei Qing Li Xuan Yao Shaoping Lu Yueyun Hong Xuemin Wang Liang Guo 《植物学报(英文版)》2023,65(11):2421-2436
Phosphorus is a major nutrient vital for plant growth and development, with a substantial amount of cellular phosphorus being used for the biosynthesis of membrane phospholipids. Here, we report that NON-SPECIFIC PHOSPHOLIPASE C4 (NPC4) in rapeseed (Brassica napus) releases phosphate from phospholipids to promote growth and seed yield, as plants with altered NPC4 levels showed significant changes in seed production under different phosphate conditions. Clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated nuclease 9 (Cas9)-mediated knockout of BnaNPC4 led to elevated accumulation of phospholipids and decreased growth, whereas overexpression (OE) of BnaNPC4 resulted in lower phospholipid contents and increased plant growth and seed production. We demonstrate that BnaNPC4 hydrolyzes phosphosphingolipids and phosphoglycerolipids in vitro, and plants with altered BnaNPC4 function displayed changes in their sphingolipid and glycerolipid contents in roots, with a greater change in glycerolipids than sphingolipids in leaves, particularly under phosphate deficiency conditions. In addition, BnaNPC4-OE plants led to the upregulation of genes involved in lipid metabolism, phosphate release, and phosphate transport and an increase in free inorganic phosphate in leaves. These results indicate that BnaNPC4 hydrolyzes phosphosphingolipids and phosphoglycerolipids in rapeseed to enhance phosphate release from membrane phospholipids and promote growth and seed production. 相似文献
63.
Jie Wang Gao-Fei Fu Luke R. Tembrock Xue-Zhu Liao Song Ge Zhi-Qiang Wu 《植物分类学报:英文版》2023,61(2):328-344
The study of genomic structural evolution associated with accelerated evolutionary rates that result in avoidance of meltdown and increase biodiversity is becoming ever more possible as the number of available plastomes increases. To more comprehensively analyze rate heterogeneity among monocots and within Poaceae, we sequenced plastomes from four Poaceae species, combined them with publicly available data from ~200 plastomes, and conducted comparative analyses to quantify the pattern of rate heterogeneity between different lineages, functional groups, and periods of evolutionary time. We compared structural differences across the Poaceae to quantify how changes in plastome size correspond to different genomic subunits and the evolution of IR–SC junction boundaries. The substitution rates among ancestral Poaceae were inferred to be exceptionally rapid compared to other monocots but slowed after divergence into extant lineages, which could not be sufficiently explained by positive selection. As such, rapid rates in the ancestral lineage leading to Poaceae might be more closely linked to large-scale structural changes like the loss of ycf1 and ycf2. The total increase in plastome size across Poaceae was positively correlated with the total length of intergenic spacers, tandem repeats, and dispersed repeats as well as large single copy, and inverted repeats (IRs). The continuous evolution of IR–SC junction boundaries was asynchronous with sizes of total genome and subunits across Poaceae. Future work is needed to better understand what factors in ancestral Poaceae evolved to harness such rapid rates of plastome evolution, avoid a mutational meltdown, and escape the stagnation of strong purifying selection as well as if these factors could be utilized to synthetically control rates. 相似文献
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65.
K Yamamoto D Okamura D Kurahara K Liao L Kimura R Simafranca J Musgrave D Person J Galario K Yamaga 《Cellular and molecular biology, including cyto-enzymology》2003,49(8):1333-1337
Glomerular inflammation is associated with urinary mononuclear cells (UMC) in a number of diseases including IgA nephropathy and glomerulonephritis. We examined UMC from children with lupus nephritis for a number of years to characterize the types of mononuclear cells found in urine and to determine if they were associated with active lupus nephritis. Detailed analysis of UMC by cell counts and by flow cytometry showed that monocytes were the clearly dominant cell type. Evaluation of the smaller number of lymphocytes found in the urine of patients with active lupus nephritis demonstrated a strong predominance of CD8+ lymphocytes, in contrast to the normal CD4+/CD8+ ratio that is found in peripheral blood. The degree of proteinuria strongly correlated with the presence of UMC. The UMC counts decreased as their clinical condition improved as indicated by lower indices of flare. These observations suggest that UMC may be a valuable tool in detecting and monitoring disease activity in patients with severe lupus nephritis. More importantly, this study indicated that both monocytes and cytotoxic CD8+ T cells may play a role in pathogenesis of lupus nephritis. 相似文献
66.
小麦Kr基因在小麦与玉米或鸭茅状摩擦禾杂交中的失活 总被引:2,自引:0,他引:2
用37个小麦(Triticumaestivum)品种(系)为母本,分别与黑麦(Secalecereale)、球茎大麦(Hordeumbulbosum)、玉米(Zeamays)和鸭茅状摩擦禾(Tripsacumdactyloides)杂交,比较其亲和性,小麦和玉米或鸭茅状摩擦禾杂交比小麦与黑麦或球茎大麦杂交的亲和性显著提高。携带着显性Kr1和Kr2基因的小麦品种Hope与黑麦杂交,不能形成胚,而与玉米及鸭茅状摩擦禾杂交时,成胚率分别达16.00%和32.50%。表明控制小麦与黑麦及球茎大麦杂交亲和性的Kr基因系统在小麦与玉米及小麦与鸭茅状摩擦禾属间杂交中失活。讨论了还存在有其它控制小麦属间杂交亲和性的遗传调控系统的可能性。 相似文献
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68.
The surface pressure-area (-A) isotherms ofN-hexadecyl-8-hydroxy-2-quinolinecarboxamide (HHQ) monolayers at an air-water interface on subphases with different pH values were investigated. The monolayer of HHQ was expanded and unstable on acidic subphases, while it was condensed and stable on basic subphases. The acid-base equilibrium of HHQ was investigated in an aqueous dioxane solution and at the air-water interface. The association-dissociation of HHQ with H+ ions in the interfacial region was very different from that in the aqueous dioxane solution. Some information regarding the packing density, phase transition and degree of ionization of the head group under different experimental conditions has been obtained. 相似文献
69.
70.
青海湖裸鲤寄生舌状绦虫的空间格局研究 总被引:3,自引:0,他引:3
舌状绦虫裂头蚴只寄生在体长小于220mm的青海湖裸鲤中,其种群在宿主种群中呈聚集分布。其聚集分布的强度随寄生虫种群平均密度的增加而降低。由于舌状绦虫在宿主体腔生长,产生明显的空间拥挤效应,可能导致宿主死亡或被食鱼鸟类捕食而转移到终末宿主中。在体长小于120mm的宿主中,密度依赖的死亡过程可能是使聚集强度降低的原因;而体长140-200mm的鱼中,则是非密度依赖的全死过程使聚集强度增加. 相似文献