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971.
972.
Banani Banerjee Bidyut K. Medda Jamie Schmidt Yue Zheng Zhihong Zhang Reza Shaker Jyoti N. Sengupta 《Histochemistry and cell biology》2009,132(6):585-597
Purinergic P2X3 receptors are predominantly expressed in small diameter primary afferent neurons and activation of these receptors by adenosine triphosphate is reported to play an important role in nociceptive signaling. The objective of this study was to investigate the expression of P2X3 receptors in spinal and vagal sensory neurons and esophageal tissues following esophagitis in rats. Two groups of rats were used including 7 days fundus-ligated (7D-ligated) esophagitis and sham-operated controls. Esophagitis was produced by ligating the fundus and partial obstruction of pylorus that initiated reflux of gastric contents. The sham-operated rats underwent midline incision without surgical manipulation of the stomach. Expressions of P2X3 receptors in thoracic dorsal root ganglia (DRGs), nodose ganglia (NGs), and esophageal tissues were evaluated by RT–PCR, western blot and immunohistochemistry. Esophageal neurons were identified by retrograde transport of Fast Blue from the esophagus. There were no significant differences in P2X3 mRNA expressions in DRGs (T1–T3) and NGs between 7D-ligated and sham-operated rats. However, there was an upregulation of P2X3 mRNA in DRGs (T6–T12) and in the esophageal muscle. At protein level, P2X3 exhibited significant upregulation both in DRGs and in NGs of rats having chronic esophagitis. Immunohistochemical analysis exhibited a significant increase in P2X3 and TRPV1 co-expression in DRGs and NGs in 7D-ligated rats compared to sham-operated rats. The present findings suggest that chronic esophagitis results in upregulation of P2X3 and its co-localization with TRPV1 receptor in vagal and spinal afferents. Changes in P2X3 expression in vagal and spinal sensory neurons may contribute to esophageal hypersensitivity following acid reflux-induced esophagitis. 相似文献
973.
974.
In order to understand the hormonal interactions throughout the reproductive phases (non-breeding, progressive, breeding and regressive) of a sub-tropical avian species, the male common myna (Acriodotheres tristis), hormones like epinephrine (E), norepinephrine (NE), corticosterone, tri-iodothyronine (T 3), thyroxine (T 4) and testosterone (along with testicular sialic acid) were quantitated. Histometry and histology of the testis and adrenal glands were also performed. It became evident that a parallel relationship exists between the reproductive phases of the common myna and levels of the hormones E, NE, corticosterone, T 3, T 4 and testosterone. Considering the ambient climatological conditions, it is suggested that primarily daylength and secondarily humidity control the gonadal cycle of this species. 相似文献
975.
976.
Mice treated with acetazolamide or cAMP received intravenously liposomes containing carbonic anhydrase. The hyperglycemic effect of both these substances was suppressed by carbonic anhydrase entrapped in liposomes. The later also abolished the glycogenolytic action of cAMP on liver. 相似文献
977.
978.
Mansoor Hussain Aftab Mohammed Shabnam Saifi Aamir Khan Ekjot Kaur Swati Priya Himanshi Agarwal Sagar Sengupta 《PLoS biology》2021,19(3)
Mutations in mitochondrial replicative polymerase PolγA lead to progressive external ophthalmoplegia (PEO). While PolγA is the known central player in mitochondrial DNA (mtDNA) replication, it is unknown whether a regulatory process exists on the mitochondrial outer membrane which controlled its entry into the mitochondria. We now demonstrate that PolγA is ubiquitylated by mitochondrial E3 ligase, MITOL (or MARCH5, RNF153). Ubiquitylation in wild-type (WT) PolγA occurs at Lysine 1060 residue via K6 linkage. Ubiquitylation of PolγA negatively regulates its binding to Tom20 and thereby its mitochondrial entry. While screening different PEO patients for mitochondrial entry, we found that a subset of the PolγA mutants is hyperubiquitylated by MITOL and interact less with Tom20. These PolγA variants cannot enter into mitochondria, instead becomes enriched in the insoluble fraction and undergo enhanced degradation. Hence, mtDNA replication, as observed via BrdU incorporation into the mtDNA, was compromised in these PEO mutants. However, by manipulating their ubiquitylation status by 2 independent techniques, these PEO mutants were reactivated, which allowed the incorporation of BrdU into mtDNA. Thus, regulated entry of non-ubiquitylated PolγA may have beneficial consequences for certain PEO patients.This study shows that mitochondrial entry of the replicative polymerase PolgA is regulated by ubiquitylation by the E3 ligase MITOL; however, by manipulating their ubiquitylation status, some progressive external ophthalmoplegia mutants whose PolgA is polyubiquitylated and cannot enter the mitochondrion can be reactivated and hence become functionally active. 相似文献
979.
Peptides from a mycobacillin-synthesizing cell-free system 总被引:5,自引:4,他引:1
In a cell-free system from Bacillus subtilis B(3), ATP-P(i) exchange was catalysed by l-proline at a pH optimum of 7.2. Further stimulation by component amino acids of mycobacillin was inhibited by deprivation from the synthesizing system of even a single amino acid occurring at any point of the cyclic peptide. This inhibition, however, decreased with the distance in the molecule of the given amino acid from l-proline. Peptides containing respectively two, three, four, five and six amino acids were isolated from the mycobacillin-synthesizing system by an amino acid-deprivation technique. The amino acid composition of these peptides and also their N- and C-terminal amino acid residues were the same as those of peptides that would be obtained if mycobacillin synthesis occurred starting from l-proline and was interrupted at various points along the polypeptide chain. 相似文献
980.
Champa Sengupta Bruce P. Brandhorst Desh Pal S. Verma 《Biochimica et Biophysica Acta (BBA)/General Subjects》1981,674(1):105-117
Achlya ambisexualis, a water mold, secretes several glycoproteins during exponential growth. Among these is a major protein of 39 000 daltons (protein A-39) which is secreted very rapidly. Protein A-39 is detected among the soluble cellular proteins labeled for 5 min. However, after longer labeling times, an additional 95 000 dalton glycoprotein was immunoprecipitated from among the cytoplasmic proteins by antiserum against protein A-39. This antiserum reacted with a single 37 000 dalton protein from the in vitro translation products of poly(A)-containing RNA in a wheat germ cell-free system which is cleaved to a faster moving component in the presence of dog pancreatic membranes. Immunoprecipitated, chain-completion products of polysomes also show a 37 000 dalton peptide which does not bind to lectins, indicating absence of co-translational cleavage and glycosylation.Tunicamycin inhibits the appearance of the 95 000 dalton protein. Several immunoprecipitable proteins, including protein A-39, having sizes identical to the secretory proteins accumulate in the cytoplasm in the presence of this inhibitor. A short pulse with [3H]glucosamine followed by a chase showed that incorporation in protein A-39 increases while that in 95 000 dalton protein is decreasing. These results suggest that the 95 000 dalton glycoprotein may serve as a glycosyl donor to secretory protein A-39. 相似文献