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941.
Liu Na Si Yanhong Zhang Ying Guo Shoudong Qin Shucun 《Journal of physiology and biochemistry》2021,77(4):683-694
Journal of Physiology and Biochemistry - Cholesteryl ester transfer protein (CETP) and phospholipid transfer protein (PLTP) belong to the same gene family. Liver-specific expression of CETP... 相似文献
942.
Plant nucleotide‐binding, leucine‐rich repeat receptors (NLRs) perceive pathogen avirulence effectors and activate defense responses. Nucleotide‐binding, leucine‐rich repeat receptors are classified into coiled‐coil (CC)‐containing and Toll/interleukin‐1 receptor (TIR)‐containing NLRs. Recent advances suggest that NLR CC domains often function in signaling activation, especially for induction of cell death. In this review, we outline our current understanding of NLR CC domains, including their diversity/classification and structure, their roles in cell death induction, disease resistance, and interaction with other proteins. Furthermore, we provide possible directions for future work. 相似文献
943.
Yuhua Wang Xuelin Zhou Jinyan Luo Suhui Lv Rui Liu Xuan Du Bei Jia Fengtong Yuan Heng Zhang Jiamu Du 《植物学报(英文版)》2021,63(6):1091-1096
RNA-directed DNA methylation (RdDM) is a plant-specific de novo DNA methylation pathway, which has extensive cross-talk with histone modifications. Here, we report that the maize RdDM regulator SAWADEE HOMEODOMAIN HOMOLOG 2 (SHH2) is an H3K9me1 reader. Our structural studies reveal that H3K9me1 recognition is achieved by recognition of the methyl group via a classic aromatic cage and hydrogen-bonding and salt-bridge interactions with the free protons of the mono-methyllysine. The di- and tri-methylation states disrupt the polar interactions, decreasing the binding affinity. Our study reveals a mono-methyllysine recognition mechanism which potentially links RdDM to H3K9me1 in maize. 相似文献
944.
Yutong Lin Luhui Kuang Songbo Tang Zhijian Mou Oliver L. Phillips Hans Lambers Zhanfeng Liu Jordi Sardans Josep Peñuelas Yuan Lai Mingxian Lin Dexiang Chen Yuanwen Kuang 《Journal of Plant Ecology》2021,14(6):1115
热带森林优势种青冈叶片气孔、解剖和形态性状与气候、土壤因子的关联
了解优势树种叶片多水平的功能性状沿海拔梯度的变化及其内在关联,有助于预测优势种应对气候变化的响应与适应。本文研究了青冈属树种叶片气孔、解剖和形态性状沿海拔梯度的变化及其与环境调控因子的关联,探究了其生态策略是否随海拔发生改变。在海南尖峰岭热带森林,沿海拔梯度(400–1400 m)采集了6种常绿青冈:竹叶青冈(Cyclobalanopsis bambusaefolia)、雷公青冈(C. hui)、托盘青冈 (C. patelliformis)、饭甄青冈(C. fleuryi)、吊罗山青冈(C. tiaoloshanica)和亮叶青冈(C. phanera)叶片,用于气孔、解剖和形态性状的测定。研究结果表明,随海拔升高,青冈树种叶片气孔密度、气孔孔隙度指数和叶面积显著增加,但海绵组织厚度比和干物质含量则显着降低。叶片气孔、解剖和形态性状沿海拔梯 度的变化主要受年均温、年降水量和土壤pH 值调控。在低海拔和高海拔处,青冈属采取“耐受”和“竞 争”策略,而在中海拔处,则是“竞争”策略。土壤磷含量和土壤pH 值随海拔的变化可能是驱动其生态 策略转变的主要原因。该结果揭示,热带森林优势树种青冈可通过从气孔细胞-组织解剖结构-叶片水平功能性状的改变来响应环境变化。 相似文献
945.
Shu Pan Fei Sun Hongcan Shi Fangbiao Zhang Xingchen Liu Weidong Zhang 《Biotechnology and Bioprocess Engineering》2014,19(5):925-934
Forty tracheas were harvested from donor New Zealand rabbits. Thirty of the tracheas were randomly divided into four treatment groups corresponding to 4, 5, 6, or 7% NaClO4 and one untreated group (n = 6 each group). Scanning electron microscopy distinctly revealed the cilium of epithelial cells in the fresh trachea. The internal surface of the trachea was rough in the 4% treatment group and smooth in the 5% treatment group, whereas the matrix was fractured in the 6% treatment group and highly fractured in the 7% treatment group. We observed that the number of nuclei in the cells of the 4, 5, 6, and 7% treatment groups decreased compared to the cells of the untreated group (p < 0.05). Although there was a significant decrease in maximum tensile strength, tensile strain at fracture and the elastic modulus (p < 0.05) with increasing concentrations of NaClO4, the content of glycosaminoglycans (GAGs) did not significantly decline (p > 0.05) in the 5% treatment group. In addition, histopathological analysis showed that the fiber component and basement membrane of the matrix in the 5% treatment group were retained after optimal decellularization. Despite the preserved cartilage, in vitro immunohistochemical analysis revealed that the matrix did not show the presence of major histocompatibility complex (MHC) antigens. The remaining ten donor tracheas, which were divided into a positive control group and an optimal decellularized group, were used for allogeneic transplantation. Blood samples were taken regularly, and histologic examinations were performed at 30 days postimplantation, which showed no significant immune rejection. In conclusion, we surveyed the structural integrity through morphological observation and compared the biomechanical and immunogenic changes in the tracheal matrix under the different treatments. The optimal decellularized tracheal matrix with preserved cartilage, which was acquired via 5% NaClO4 treatment, exhibited structural integrity, antigen cell removal and immune privilege and would be suitable for use as a tissue-engineered trachea for in vivo transplantation in rabbit models. 相似文献
946.
947.
Sex identification and genetic variation of Saccharina (Phaeophyta) gametophytes as revealed by inter-simple sequence repeat (ISSR) markers 总被引:1,自引:0,他引:1
Jun-Gang Gu Yu-Ping Sun Yu Liu Yan-Hui Bi Zhi-Gang Zhou 《Journal of applied phycology》2014,26(1):635-646
Inter-simple sequence repeat (ISSR) polymerase chain reaction (PCR) markers were utilized to investigate the genetic variation between male and female gametophyte populations of strains Rongfu and 901 of Saccharina. In total, 11 ISSR primers were able to generate 135 satisfactory and reproducible loci, of which 134 were polymorphic with 99.26 % polymorphism. The percentages of polymorphism of female gametophyte populations (60 and 62 % for their respective strains) were higher than those of the males (53 %), and the Nei’s genetic diversity and Shannon’s information index showed a similar tendency. The clustering of gametophytes of the same sex from each strain was well resolved by both an unweighted paired group method using the arithmetic average and a principal component analysis, suggesting that any male/female gametophyte pair could represent each strain. However, a single pair was not adequate for germplasm maintenance because the genetic variance among individuals within a population accounted for 57.45 % of the total (P?<?0.0001), as shown by the analysis of molecular variance. The gametophyte sex could be identified by amplification with primer UBC809 because of a differential band present in the females. According to the sequence of this band, a pair of ISSR-derived sequence-characterized amplified region (SCAR) primers was designed. With the primers, one female-specific fragment was detected using PCR and Southern blot hybridization. This converted SCAR marker was localized on one unique chromosome of the female gametophytes of these two strains by use of fluorescence in situ hybridization, confirming that it was a female chromosome-specific marker. 相似文献
948.
Lei Dong Hong Ming Yi-Rui Yin Yan-Yan Duan En-Min Zhou Guo-Xing Nie Hui-Geng Feng Lan Liu Wen-Jun Li 《Antonie van Leeuwenhoek》2014,105(5):899-905
An alkalitolerant, thermotolerant and Gram-stain negative bacterium, designated strain YIM 78007T, was isolated from an alkaline geothermal soil sample from Hehua hot spring, Tengchong, Yunnan province, south-west China. Cells of strain YIM 78007T were observed to be aerobic and short rod-shaped. The colonies were observed to be orange-red, convex and circular. 16S rRNA gene sequence-based phylogenetic analysis showed that strain YIM 78007T clustered with members of the genus Roseomonas (with similarities from 97.2 to 92.2 %). Optimal growth of strain YIM 78007 occurs at 40–50 °C and pH 8.0–10.0. The predominant ubiquinone was identified as Q-10 and the major fatty acids were identified as C18:1 ω7c and C16:0. The polar lipids were identified as diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, two unidentified aminolipids and one unknown phospholipid. The G + C content of the genomic DNA was determined to be 63 mol %. The levels of DNA–DNA hybridization relatedness between strain YIM 78007T and its closet neighbours (Roseomonas lacus JCM 13283T and Roseomonas terrae JCM 14592T) were well below the threshold required for the proposal of a novel species. The results of physiological and biochemical characteristics, the phylogenetic analysis, as well as low DNA–DNA hybridization values, allowed the phenotypic and genotypic differentiation of strain YIM 78007T from its closest phylogenetic neighbours. Therefore, strain YIM 78007T is considered to represent a novel species of the genus Roseomonas, for which the name Roseomonas alkaliterrae sp. nov. is proposed. The type strain is YIM 78007T (=BCRC 80644T = JCM 19656T). 相似文献
949.
The refractive index resolution of a surface plasmon resonance (SPR) sensor has been significantly improved these years; however, higher sensing performance is always desired. In this work, we propose a line-monitoring, long-range SPR sensor whose resolution is much better than conventional SPR sensors. Also, in contrast to mono-channel detection, multichannel detection, using line-monitoring technique, can detect multiple channels concurrently. In this way, this system achieves a refractive index resolution of 4.0?×?10??7 refractive index units and can monitor multiple molecular interactions simultaneously. Finally, a model experiment detecting the Escherichia coli bacteria has demonstrated the potential for biomedical applications of this system. 相似文献
950.
Kun Liu Xin Hong Shou-Biao Zhou Yang-Song Cheng Cheng-Feng Tang Hui-Juan Xu 《Plant Systematics and Evolution》2014,300(7):1615-1620
A new species of Myrsinaceae, Lysimachia jinzhaiensis S.B. Zhou & K. Liu, is described and illustrated from Dabieshan mountain, Anhui, China. It is similar to L. christiniae in the prostrate stem, opposite leaves, yellow flowers born singly in leaf axils, but differs by being glabrous throughout or glandular on young parts, and having quadrangular stem, corolla with densely transparent glandular, orange-red corolla base with lobes being significantly overlapping and contorting to left in bud. Moreover, L. jinzhaiensis have a different karyotype, formulated as 2n = 2m + 2sm + 10st (2SAT) + 10t. 相似文献