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1.
The process of crop domestication occurs through the selection and subsequent propagation of novel alleles that improve traits of interest. Cultivated tomato (Solanum lycopersicum), particularly heirloom varieties, exhibit a wide range of variation in fruit size, shape and color. The green-flesh mutant of tomato possesses a stay-green phenotype resulting in fruits that ripen to a red-brown color, due to the retention of chlorophyll and the simultaneous accumulation of lycopene. The recent identification of the GREEN-FLESH gene provides a molecular tool with which to investigate the origin of a subset of cultivated tomato varieties that resemble the green-flesh mutant. Sequence analysis of the GF locus from 26 varieties revealed the existence of four previously unidentified null alleles. This study illustrates the potential of cultivated tomato varieties, including heritage cultivars, heirlooms, and land races, for uncovering new alleles in genes of interest.  相似文献   
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The role of invariant water molecules in the activity of plant cysteine protease is ubiquitous in nature. On analysing the 11 different Protein DataBank (PDB) structures of plant thiol proteases, the two invariant water molecules W1 and W2 (W220 and W222 in the template 1PPN structure) were observed to form H-bonds with the Ob atom of Asn 175. Extensive energy minimization and molecular dynamics simulation studies up to 2 ns on all the PDB and solvated structures clearly revealed the involvement of the H-bonding association of the two water molecules in fixing the orientation of the asparagine residue of the catalytic triad. From this study, it is suggested that H-bonding of the water molecule at the W1 invariant site better stabilizes the Asn residue at the active site of the catalytic triad.  相似文献   
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Journal of Plant Growth Regulation - Crop improvement in light of the rapidly changing climate and the increasing human population continues to be one of the primary concerns for researchers across...  相似文献   
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The Ventilago Gaertn. (Rhamnaceae) is widely distributed in pantropical areas of Africa, Asia, and Australia. However, fossil records of this taxon are sparse, which limits understanding of the evolution and biogeographic history of the genus. In the present study, we report and describe two new fossil species of Ventilago, V. siwalika sp. nov. from the Miocene sediments of Himachal Pradesh, western Himalaya, and V. pliocenica sp. nov. from the Pliocene sediments of Jharkhand, eastern India based on single-winged samaras. Ventilago pliocenica is characterized by a prominent midvein, obtuse to sub-round apex with mucronate tip, longitudinal secondary veins extending the full length of the fruit, and reticulate nature of higher-order veins, the presence of equatorial rim, the hypanthium, and short pedicel. On the other hand, V. siwalika is characterized by a prominent midvein, obtuse to sub-round apex with mucronate tip, longitudinal secondary veins extending the full length of the fruit, and reticulate nature of higher-order veins. Our discovery represents the first unambiguous fossil record of single-winged samara of Ventilago from India and provides valuable insights into the evolution of this genus. In this paper, we also review its biogeographic history and add new information to understand its hypothetical migration route. Present and earlier records of Ventilago also suggest that this genus was a common forest element during Neogene (Miocene time) in Asia.  相似文献   
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Entamoeba histolytica is a protist parasite that is the causative agent of amoebiasis, and is a highly motile organism. The motility is essential for its survival and pathogenesis, and a dynamic actin cytoskeleton is required for this process. EhCoactosin, an actin-binding protein of the ADF/cofilin family, participates in actin dynamics, and here we report our studies of this protein using both structural and functional approaches. The X-ray crystal structure of EhCoactosin resembles that of human coactosin-like protein, with major differences in the distribution of surface charges and the orientation of terminal regions. According to in vitro binding assays, full-length EhCoactosin binds both F- and G-actin. Instead of acting to depolymerize or severe F-actin, EhCoactosin directly stabilizes the polymer. When EhCoactosin was visualized in E. histolytica cells using either confocal imaging or total internal reflectance microscopy, it was found to colocalize with F-actin at phagocytic cups. Over-expression of this protein stabilized F-actin and inhibited the phagocytic process. EhCoactosin appears to be an unusual type of coactosin involved in E. histolytica actin dynamics.  相似文献   
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In the recent past, huge emphasis has been given to the epigenetic alterations of the genes responsible for the cause of neurological disorders. Earlier, the scientists believed somatic changes and modifications in the genetic makeup of DNA to be the main cause of the neurodegenerative diseases. With the increase in understanding of the neural network and associated diseases, it was observed that alterations in the gene expression were not always originated by the change in the genetic sequence. For this reason, extensive research has been conducted to understand the role of epigenetics in the pathophysiology of several neurological disorders including Alzheimer’s disease, Parkinson’s disease and, Huntington’s disease. In a healthy person, the epigenetic modifications play a crucial role in maintaining the homeostasis of a cell by either up-regulating or down-regulating the genes. Therefore, improved understanding of these modifications may provide better insight about the diseases and may serve as potential therapeutic targets for their treatment. The present review describes various epigenetic modifications involved in the pathology of Parkinson’s Disease (PD) backed by multiple researches carried out to study the gene expression regulation related to the epigenetic alterations. Additionally, we will briefly go through the current scenario about the various treatment therapies including small molecules and multiple phytochemicals potent enough to reverse these alterations and the future directions for a better management of PD.

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