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111.
Paul J. Focke Craig A. Schiltz Sharon E. Jones Jyoti J. Watters Miles L. Epstein 《Developmental neurobiology》2001,47(4):306-317
The enteric nervous system (ENS) develops from neural crest cells that enter the gut, migrate, proliferate, and differentiate into neurons and glia. The growth factor glial‐derived neurotrophic factor (GDNF) stimulates the proliferation and survival of enteric crest‐derived cells. We investigated the intracellular signaling pathways activated by GDNF and their involvement in proliferation. We found that GDNF stimulates the phosphorylation of both the PI 3‐kinase downstream substrate Akt and the MAP kinase substrate ERK in cultures of immunoaffinity‐purified embryonic avian enteric crest‐derived cells. The selective PI 3‐kinase inhibitor LY‐294002 blocked GDNF‐stimulated Akt phosphorylation in purified crest cells, and reduced proliferation in cultures of dissociated quail gut. The ERK kinase (MEK) inhibitors PD 98059 and UO126 did not reduce GDNF‐stimulated proliferation, although PD 98059 blocked GDNF‐stimulated phosphorylation of ERK. We conclude that the PI 3‐kinase pathway is necessary for the GDNF‐stimulated proliferation of enteric neuroblasts. © 2001 John Wiley & Sons, Inc. J Neurobiol 47: 306–317, 2001 相似文献
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113.
The activities of enzymes of pentose phosphate pathway (PPP) viz. glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase and carbon metabolism viz. phosphoenol pyruvate carboxylase, NADP- isocitrate dehydrogenase and NADP-malic enzyme were measured in the plant and bacteroid
fractions of mungbean (ureide exporter) and lentil (amide exporter) nodules along with the developing roots for comparison.
The enzymes of pentose phosphate pathway in legume cytosol had higher activities at a stage of maximum nitrogenase activity
and higher sucrose metabolism. However, bacteroids had only limited capacity for this pathway. The specific activities of
these enzymes were greater in ureide than in amide exporter. CO2 fixation via higher activity of phosphoenolpyruvate carboxylase in the plant part of the nodules in lentil might have been due to the
greater synthesis of four carbon amino acids for amide export. The peak of NADP-isocitrate dehydrogenase in both legumes coincided
with the pentose phosphate pathway enzymes at the time of high rates of sucrose metabolism and nitrogen fixation. Higher activities
of NADP-malic enzyme were obtained in mungbean than in the lentil nodules. These findings are consistent with the role of
these enzymes in providing reductant (NADPH) and substrates for energy yielding metabolism of bacteroids and carbon skeletons
for ammonia assimilation. 相似文献
114.
Gastro-respiratory tract of the loach,Lepidocephalichthys guntea has been studied with special reference to the nature of its mucus secreting epithelia. The mucous cells are strongly PAS-positive and their number per unit area (mm2) in the mucosal layers of oesophagus, intestinal bulb, intestine and rectum are 733, 531, 223 and 540, respectively. The air-breathing segment of the gut is completely devoid of neutral mucosubstances, and there is a predominance of acidic mucosubstances over the neutral ones throughout the digestive tube. The air-blood pathway of the accessory respiratory organ is about 2.6 μm which is higher than the values of air-breathing organs of other fishes. 相似文献
115.
116.
Vibha Pandey Rakesh Srivastava Nehal Akhtar Jyoti Mishra Pratibha Mishra Praveen C. Verma 《Plant Molecular Biology Reporter》2016,34(3):681-689
In Withania somnifera, sterol molecules of immense medicinal value are diversified by means of glycosylation. Identifying sterol glycosyltransferases provides an imperative insight of diverse sterol modifications, thereby helping to comprehend the underlying plant mechanisms. In the present study, one of the W. somnifera sterol glycosyltransferase-4 (Ws-Sgtl4) gene was transformed into the W. somnifera leaf explant through Agrobacterium rhizogene. Transformed W. Somnifera Ws-Sgtl4 leaf explants were subjected to hairy root induction and analyzed for biomass accumulation. The analysis of Ws-Sgtl4 gene expression was performed at different time exposures with the application of salicylic acid and methyl jasmonate. The elicitation of W. somnifera hairy root expressing the Ws-Sgtl4 gene was also evaluated for the enhancement if any, in the total withanolide yield as well as the withanolides-A contents. The results suggested that Ws-Sgtl4 gene expression enhanced the production of total withanolide yield and withanolides-A in the hairy root culture of W. somnifera in the response to the elicitors. 相似文献
117.
118.
Y. Bhargav Kumar Nandan Kumar Lijo John Hridoy Jyoti Mahanta S. Vaikundamani Selvaraman Nagamani G. Madhavi Sastry G. Narahari Sastry 《Proteins》2024,92(2):179-191
The cation-aromatic database (CAD) is a comprehensive repository of cation-aromatic motifs found in experimentally determined protein structures, first reported in 2007 [Proteins, 2007, 67, 1179]. The present article is an update of CAD that contains information of approximately 27.26 million cation-aromatic motifs. CAD uses three distance parameters (r, d1, and d2) to determine the position of the cation relative to the centroid of the aromatic residue and classifies the motifs as cation-π or cation-σ interactions. As of June 2023, about 193 936 protein structures were retrieved from Protein Data Bank, and this resulted in the identification of an impressive number of 27 255 817 cation-aromatic motifs. Among these motifs, spherical motifs constituted 94.09%, while cylindrical motifs made up the remaining 5.91%. When considering the interaction of metal ions with aromatic residues, 965 564 motifs are identified. Remarkably, 82.08% of these motifs involved the binding of metal ions to the amino acid HIS. Moreover, the analysis of binding preferences between cations and aromatic residues revealed that the HIS-HIS, PHE-ARG, and TRP-ARG pairs exhibited a preferential geometry. The motif pair HIS-HIS was the most prevalent, accounting for 19.87% of the total, closely followed by TYR-LYS at 10.17%. Conversely, the motif pair TRP-HIS had the lowest occurrence, representing only 4.20% of the total. The data generated help in revealing the characteristics and biological functions of cation-aromatic interactions in biological molecules. The updated version of CAD (Cation-Aromatic Database V2.0) can be accessed at https://acds.neist.res.in/cadv2 . 相似文献
119.
Jyoti Mareddy N. Suresh C. Ganesh Kumar Ravikumar Kapavarapu A. Jayasree Sarbani Pal 《Bioorganic & medicinal chemistry letters》2017,27(3):518-523
A new hybrid template has been designed by integrating the structural features of nimesulide and the 1,2,3-triazole moiety in a single molecular entity at the same time eliminating the problematic nitro group of nimesulide. The template has been used for the generation of a library of molecules as potential anticancer agents. A mild and greener CuAAC approach has been used to synthesize these compounds via the reaction of 4-azido derivative of nimesulide and terminal alkynes in water. Three of these compounds showed promising growth inhibition (IC50 ~6–10 μM) of A549, HepG2, HeLa and DU145 cancer cell lines but no significant effects on HEK293 cell line. They also inhibited PDE4B in vitro (60–70% at 10 μM) that was supported by the docking studies (PLP score 87–94) in silico. 相似文献
120.
Daryl L. Klindworth Jyoti Saini Yunming Long Matthew N. Rouse Justin D. Faris Yue Jin Steven S. Xu 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2017,130(6):1135-1154