The role of RNA in the maintenance of chromatin domains as revealed by antibody-mediated proximity labelling coupled to mass spectrometry.

Eukaryotic chromatin is organized into functional domains, that are characterized by distinct proteomic compositions and specific nuclear positions. In contrast to cellular organelles surrounded by lipid membranes, the composition of distinct chromatin domains is rather ill described and highly dynamic. To gain molecular insight into these domains and explore their composition, we developed an antibody-based proximity biotinylation method targeting the RNA and proteins constituents.

Iodotyrosines Are Biomarkers for Preclinical Stages of Iodine-Deficient Hypothyroidism in -Knockout Mice.

Iodine is required for the synthesis of thyroid hormone (TH), but its natural availability is limited. Dehalogenase1 (Dehal1) recycles iodine from mono- and diiodotyrosines (MIT, DIT) to sustain TH synthesis when iodine supplies are scarce, but its role in the dynamics of storage and conservation of iodine is unknown. -knockout (KO) mice were generated by gene trapping.

Congenital Hypothyroidism in Two Sudanese Families Harboring a Novel Iodotyrosine Deiodinase Mutation (IYD R279C).

Congenital hypothyroidism due to defects in iodotyrosine deiodinase has variable phenotypes and can present as hypothyroid or with normal thyroid testing. Whole exome sequencing was performed in individuals from two families originating from different regions of Sudan. Mass spectrometry of urine and serum iodotyrosines was performed on subjects from both families.

Screening for eukaryotic motifs in reveals Smh1 as bacterial deacetylase of host histones.

(.) is a bacterial pathogen which is a common causative agent of pneumonia. In humans, it infects alveolar macrophages and transfers hundreds of virulence factors that interfere with cellular signalling pathways and the transcriptomic landscape to sustain its own replication.

Exogenous 3-Iodothyronamine (TAM) Can Affect Phosphorylation of Proteins Involved on Signal Transduction Pathways in In Vitro Models of Brain Cell Lines, but These Effects Are Not Strengthened by Its Catabolite, 3-Iodothyroacetic Acid (TA).

TAM, a derivative of thyroid hormones, and its major catabolite, TA, produce effects on memory acquisition in rodents. In the present study, we compared the effects of exogenous TAM and TA on protein belonging to signal transduction pathways, assuming that TA may strengthen TAM's effects in brain tissue. A hybrid line of cancer cells of mouse neuroblastoma and rat glioma (NG 108-15), as well as a human glioblastoma cell line (U-87 MG) were used.

Delivery of Thyronamines (TAMs) to the Brain: A Preliminary Study.

Recent reports highlighted the significant neuroprotective effects of thyronamines (TAMs), a class of endogenous thyroid hormone derivatives. In particular, 3-iodothyronamine (T1AM) has been shown to play a pleiotropic role in neurodegeneration by modulating energy metabolism and neurological functions in mice. However, the pharmacological response to T1AM might be influenced by tissue metabolism, which is known to convert T1AM into its catabolite 3-iodothyroacetic acid (TA1).

TAM-TAAR1 signalling protects against OGD-induced synaptic dysfunction in the entorhinal cortex.

Abnormalities in thyroid hormones (TH) availability and/or metabolism have been hypothesized to contribute to Alzheimer's disease (AD) and to be a risk factor for stroke. Recently, 3-iodothyronamine (TAM), an endogenous amine putatively derived from TH metabolism, gained interest for its ability to promote learning and memory in the mouse. Moreover, TAM has been demonstrated to rescue the β-Amyloid dependent LTP impairment in the entorhinal cortex (EC), a brain area crucially involved in learning and memory and early affected during AD.

Mass spectrometry in the diagnosis of thyroid disease and in the study of thyroid hormone metabolism.

The importance of thyroid hormones in the regulation of development, growth, and energy metabolism is well known. Over the last decades, mass spectrometry has been extensively used to investigate thyroid hormone metabolism and to discover and characterize new molecules involved in thyroid hormones production, such as thyrotropin-releasing hormone. In the earlier period, the quantification methods, usually based on gas chromatography-mass spectrometry, were complicated and time consuming.

Eukaryotic and Prokaryotic Phytochelatin Synthases Differ Less in Functional Terms Than Previously Thought: A Comparative Analysis of and sp. PCC 7407.

This paper reports functional studies on the enzyme phytochelatin synthase in the liverwort and the cyanobacterium sp. strain PCC 7407. In vitro activity assays in control samples (cadmium-untreated) showed that phytochelatin synthase was constitutively expressed in both organisms.

The Moss Counteracts Severe Cadmium Stress by Activation of Glutathione Transferase and Phytochelatin Synthase, but Slightly by Phytochelatins.

In the present work, we investigated the response to Cd in , a cosmopolitan moss (Bryophyta) that can accumulate higher amounts of metals than other plants, even angiosperms, with absence or slight apparent damage. High-performance liquid chromatography followed by electrospray ionization tandem mass spectrometry of extracts from gametophytes, exposed to 0, 36 and 360 µM Cd for 7 days, revealed the presence of γ-glutamylcysteine (γ-EC), reduced glutathione (GSH), and traces of phytochelatins. The increase in Cd concentrations progressively augmented reactive oxygen species levels, with activation of both antioxidant (catalase and superoxide dismutase) and detoxifying (glutathione-transferase) enzymes.

Exogenous 3-Iodothyronamine Rescues the Entorhinal Cortex from β-Amyloid Toxicity.

A novel form of thyroid hormone (TH) signaling is represented by 3-iodothyronamine (TAM), an endogenous TH derivative that interacts with specific molecular targets, including trace amine-associated receptor 1 (TAAR), and induces pro-learning and anti-amnestic effects in mice. Dysregulation of TH signaling has long been hypothesized to play a role in Alzheimer's disease (AD). In the present investigation, we explored the neuroprotective role of TAM in beta amyloid (Aβ)-induced synaptic and behavioral impairment, focusing on the entorhinal cortex (EC), an area that is affected early by AD pathology.

Characterization and quantification of thiol-peptides in Arabidopsis thaliana using combined dilution and high sensitivity HPLC-ESI-MS-MS.

Although thiol-peptide compounds, such as reduced glutathione (GSH), γ-glutamylcysteine (γ-EC), and phytochelatins, play fundamental roles in plants, their analytical determination and characterization is still somewhat problematic, mainly due to their high polarity and oxidation propensity. Thus, in this work a reliable and sensitive HPLC-ESI-MS-MS method was developed, in order to simultaneously assay, within 14-min instrumental runs, γ-EC, GSH, and phytochelatins up to phytochelatin 4. This analytical method was validated in shoot and root extracts of the model plant Arabidopsis thaliana (Brassicaceae) and guaranteed accurate quantification by using specific isotope labelled-internal standards for both GSH and phytochelatins, as well as standards for external calibration.

Assay of Endogenous 3,5-diiodo-L-thyronine (3,5-T) and 3,3'-diiodo-L-thyronine (3,3'-T) in Human Serum: A Feasibility Study.

3,5-diiodo-L-thyronine (3,5-T2) is an endogenous derivative of thyroid hormone with potential metabolic effects. It has been detected in human blood by immunological methods, but a reliable assay based on mass spectrometry (MS), which is now regarded as the gold standard in clinical chemistry, is not available yet. Therefore, we aimed at developing a novel optimized method to quantitate 3,5-T2 and its isomers by MS in human serum.