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11.
Arumugam Velusamy Venkatesan Manigandan Ramachandran Karthik Ramachandran Saravanan Palanisamy Satheesh Kumar Sundaresan Umamaheswari 《International journal of peptide research and therapeutics》2020,26(1):201-208
International Journal of Peptide Research and Therapeutics - Marine ecosystems are unique and a largely diverse chest of natural resources which are still to be explored for new marine species.... 相似文献
12.
Rodrigues Vereena Kumar Amit Gokul Sivaraman Verma Ram S. Rahman Laiq ur Sundaresan Velusamy 《In vitro cellular & developmental biology. Plant》2020,56(4):526-537
In Vitro Cellular & Developmental Biology - Plant - An efficient in vitro propagation and synthetic seed production protocol was established for the conservation of Decalepis salicifolia (Bedd.... 相似文献
13.
María Victoria Martin Diego Fernando Fiol Venkatesan Sundaresan Eduardo Julián Zabaleta Gabriela Carolina Pagnussat 《The Plant cell》2013,25(5):1573-1591
Reactive oxygen species (ROS) can function as signaling molecules, regulating key aspects of plant development, or as toxic compounds leading to oxidative damage. In this article, we show that the regulation of ROS production during megagametogenesis is largely dependent on MSD1, a mitochondrial Mn-superoxide dismutase. Wild-type mature embryo sacs show ROS exclusively in the central cell, which appears to be the main source of ROS before pollination. Accordingly, MSD1 shows a complementary expression pattern. MSD1 expression is elevated in the egg apparatus at maturity but is downregulated in the central cell. The oiwa mutants are characterized by high levels of ROS detectable in both the central cell and the micropylar cells. Remarkably, egg apparatus cells in oiwa show central cell features, indicating that high levels of ROS result in the expression of central cell characteristic genes. Notably, ROS are detected in synergid cells after pollination. This ROS burst depends on stigma pollination but precedes fertilization, suggesting that embryo sacs sense the imminent arrival of pollen tubes and respond by generating an oxidative environment. Altogether, we show that ROS play a crucial role during female gametogenesis and fertilization. MSD1 activity seems critical for maintaining ROS localization and important for embryo sac patterning. 相似文献
14.
Ram S. Verma Amit Chauhan Rajendra C. Padalia Sanjeev K. Jat Sanjog Thul Velusamy Sundaresan 《化学与生物多样性》2013,10(4):628-641
Murraya koenigii (L.) Spreng. (Rutaceae), commonly known as ‘curry leaf tree’, is a popular spice and condiment of India. To explore the diversity of the essential‐oil yield and aroma profile of curry leaf, growing wild in foot and mid hills of north India, 58 populations were collected during spring season. M. koenigii populations were found to grow up to an altitude of 1487 m in north India. Comparative results showed considerable variations in the essential‐oil yield and composition. The essential‐oil yield varied from 0.14 to 0.80% in shade‐dried leaves of different populations of M. koenigii. Analysis of the essential oils by GC and GC/MS, and the subsequent classification by statistical analysis resulted in four clusters with significant variations in their terpenoid composition. Major components of the essential oils of investigated populations were α‐pinene ( 2 ; 4.5–71.5%), sabinene ( 3 ; <0.05–66.1%), (E)‐caryophyllene ( 11 ; 1.6–18.0%), β‐pinene ( 4 ; <0.05–13.6%), terpinen‐4‐ol ( 9 ; 0.0–8.4%), γ‐terpinene ( 8 ; 0.2–7.4%), limonene ( 7 ; 1.1–5.5%), α‐terpinene ( 6 ; 0.0–4.5%), (E)‐nerolidol ( 14 ; 0.0–4.1%), α‐humulene ( 12 ; 0.6–3.5%), α‐thujene ( 1 ; 0.0–2.5%), β‐elemene ( 10 ; 0.2–2.4%), β‐selinene ( 13 ; 0.2–2.3%), and myrcene ( 5 ; 0.5–2.1%). Comparison of the present results with those in earlier reports revealed new chemotypes of M. koenigii in investigated populations from Western Himalaya. The present study documents M. koenigii populations having higher amounts of sabinene ( 3 ; up to 66.1%) for the first time. 相似文献
15.
Santosh George Bruno Levecke Deepthi Kattula Vasanthakumar Velusamy Sheela Roy Peter Geldhof Rajiv Sarkar Gagandeep Kang 《PLoS neglected tropical diseases》2016,10(8)
BackgroundHookworms (Necator americanus and Ancylostoma duodenale) remain a major public health problem worldwide. Infections with hookworms (e.g., A. caninum, A. ceylanicum and A. braziliense) are also prevalent in dogs, but the role of dogs as a reservoir for zoonotic hookworm infections in humans needs to be further explored.Conclusions/SignificanceIn our study we regularly detected the presence of A. caninum DNA in the stool of humans. Whether this is the result of infection is currently unknown but it does warrant a closer look at dogs as a potential reservoir. 相似文献
16.
N-Phthaloyl gamma-aminobutyric acid (P-GABA) was administered to Wistar rats and 24 hr rhythms of glucose, cholesterol, total protein and lactic acid levels in blood were studied under semi-natural light dark conditions. P-GABA administration caused desynchronisation of the rhythms; while glucose and lactic acid rhythms were advanced, cholesterol and total protein rhythms were delayed. Since GABA is being involved in conveying dark information to the clock, exogenous administration of P-GABA may reduce the photic information received by the clock. The results could be explained by slightly less than 1 hr daily delays (or) advances respectively which would bring the peak times to the points 21 days after the start of administration. 相似文献
17.
Analysis of flanking sequences from dissociation insertion lines: a database for reverse genetics in Arabidopsis 总被引:15,自引:0,他引:15
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We have generated Dissociation (Ds) element insertions throughout the Arabidopsis genome as a means of random mutagenesis. Here, we present the molecular analysis of genomic sequences that flank the Ds insertions of 931 independent transposant lines. Flanking sequences from 511 lines proved to be identical or homologous to DNA or protein sequences in public databases, and disruptions within known or putative genes were indicated for 354 lines. Because a significant portion (45%) of the insertions occurred within sequences defined by GenBank BAC and P1 clones, we were able to assess the distribution of Ds insertions throughout the genome. We discovered a significant preference for Ds transposition to the regions adjacent to nucleolus organizer regions on chromosomes 2 and 4. Otherwise, the mapped insertions appeared to be evenly dispersed throughout the genome. For any given gene, insertions preferentially occurred at the 5' end, although disruption was clearly possible at any intragenic position. The insertion sites of >500 lines that could be characterized by reference to public databases are presented in a tabular format at http://www.plantcell. org/cgi/content/full/11/12/2263/DC1. This database should be of value to researchers using reverse genetics approaches to determine gene function. 相似文献
18.
Sridhar R Perumal PT Etti S Shanmugam G Ponnuswamy MN Prabavathy VR Mathivanan N 《Bioorganic & medicinal chemistry letters》2004,14(24):6035-6040
In a SAR study, we have synthesized a few 1H-pyrazole carboxylate related microbicides using Vilsmeier reagent. The anti-microbial screening results of 1H-pyrazole-3-carboxylate are reported here for the first time. The effect of 1H-pyrazole carboxylates on the mycelial growth of plant pathogenic fungi is revealed. The first X-ray structure in the family of microbicidal 1H-pyrazole-4-carboxylates is presented. 相似文献
19.
Farndale RW Siljander PR Onley DJ Sundaresan P Knight CG Barnes MJ 《Biochemical Society symposium》2003,(70):81-94
The collagen-platelet interaction is central to haemostasis and may be a critical determinant of arterial thrombosis, where subendothelium is exposed after rupture of atherosclerotic plaque. Recent research has capitalized on the cloning of an important signalling receptor for collagen, glycoprotein VI, which is expressed only on platelets, and on the use of collagen-mimetic peptides as specific tools for both glycoprotein VI and integrin alpha 2 beta 1. We have identified sequences, GPO and GFOGER (where O denotes hydroxyproline), within collagen that are recognized by the collagen receptors glycoprotein VI and integrin alpha 2 beta 1 respectively, allowing their signalling properties and specific functional roles to be examined. Triple-helical peptides containing these sequences were used to show the signalling potential of integrin alpha 2 beta 1, and to confirm its important contribution to platelet adhesion. Glycoprotein VI appears to operate functionally on the platelet surface as a dimer, which recognizes GPO motifs that are separated by four triplets of collagen sequence. These advances will allow the relationship between the structure of collagen and its haemostatic activity to be established. 相似文献
20.
Development of the female gametophyte involves several rounds of nuclear divisions during which nuclei are rearranged and finally cellularized to form a mature seven-celled embryo sac. During these nuclear divisions, key proteins involved in the cell cycle need to be degraded quickly in order to facilitate both the metaphase-anaphase transition stage and late anaphase. Here, we report the characterization of an Arabidopsis mutant nomega, which results in arrest of the embryo sac development at the two-nucleate stage. The NOMEGA gene product shows high homology to the APC6/cell division cycle (CDC)16 subunit of the Anaphase Promoting Complex/Cyclosome (APC/C). The phenotype of the nomega mutant is quite different from that of the hobbit mutant, which had suggested a role for the plant APC/C in auxin signalling. We show that nomega mutant embryo sacs are unable to degrade Cyclin B, an important APC/C substrate, providing further evidence of a role for the NOMEGA gene product and the plant APC/C in cell cycle progression during gametophyte development. 相似文献