The conformation of the CCSSCC moiety in oxytocin and lysine vasopressin is investigated using laser Raman spectroscopy. The Raman spectra of solutions of these hormones in water and in dimethyl sulfoxide show an intense band at 508 cm-1 which is assigned to the S-S stretching mode. The presence of shoulders on this band between 490 and 525 cm-1 shows that there is an equilibrium among several conformations for the disulfide unit of these hormones in solution. Most of the CS-SC dihedral angles are within 30 degrees of +/-90 degrees, but some of the molecules have CS-SC dihedral angles strained away from this value by more than 30 degrees. The previously published circular dichroism spectra of these hormones are reinterpreted, and it is shown that the circular dichroism spectra indicate the presence of more than one conformation for the disulfide unit, in agreement with the Raman results.
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http://dx.doi.org/10.1021/bi00639a018 | DOI Listing |
Neurochem Res
May 2024
Department of Bioscience and Technology for Food, Agriculture and Environment, University of Teramo, Via Renato Balzarini, 1, 64100, Teramo, Italy.
Social isolation is a state of lack of social connections, involving the modulation of different molecular signalling cascades and associated with high risk of mental health issues. To investigate if and how gene expression is modulated by social experience at the central level, we analyzed the effects of 5 weeks of social isolation in rats focusing on endocannabinoid system genes transcription in key brain regions involved in emotional control. We observed selective reduction in mRNA levels for fatty acid amide hydrolase (Faah) and cannabinoid receptor type 1 (Cnr1) genes in the amygdala complex and of Cnr1 in the prefrontal cortex of socially isolated rats when compared to controls, and these changes appear to be partially driven by trimethylation of Lysine 27 and acetylation of Lysine 9 at Histone 3.
View Article and Find Full Text PDFChem Commun (Camb)
November 2023
School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200241, P. R. China.
Herein, we designed alkylated lysine-dendron oxytocin amphiphiles (ALOAs) 1G-OTK and 2G-OTK, which were self-assembled into spherical nanoparticles and nanostrips, respectively, and showed superior stability compared to native oxytocin. We found similar trends in the functional activity of ALOAs and native OT for human oxytocin receptor. This work may inspire the development of peptide drugs for clinical applications.
View Article and Find Full Text PDFFront Behav Neurosci
October 2020
Department of Psychiatry and Behavioral Sciences, Feinberg School of Medicine, Chicago, IL, United States.
A well-studied subject of epigenetics, the histone methylation located at lysine and arginine is overseen via methyltransferases and demethylases. Lysine-specific demethylase 4A (KDM4A) comprises a lysine demethylase and possesses specificity for H3K9me3 and H3K36me3, which is capable of being used in order to activate histone transcription. Our team examined the expression of KDM4A within Sprague Dawley (SD) rats and further investigated the mechanism via which this phenomena regulates osteogenic variation within the present study.
View Article and Find Full Text PDFPLoS Biol
July 2020
Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada.
During gestation, uterine smooth muscle cells transition from a state of quiescence to one of contractility, but the molecular mechanisms underlying this transition at a genomic level are not well-known. To better understand these events, we evaluated the epigenetic landscape of the mouse myometrium during the pregnant, laboring, and postpartum stages. We generated gestational time point-specific enrichment profiles for histone H3 acetylation on lysine residue 27 (H3K27ac), histone H3 trimethylation of lysine residue 4 (H3K4me3), and RNA polymerase II (RNAPII) occupancy by chromatin immunoprecipitation with massively parallel sequencing (ChIP-seq), as well as gene expression profiles by total RNA-sequencing (RNA-seq).
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