98%
921
2 minutes
20
Purines are essential molecules formed in a highly regulated pathway in all organisms. In tropical legumes, the nitrogen fixed in the nodules is used to generate ureides through the oxidation of de novo synthesized purines. Glutamine phosphoribosyl pyrophosphate amidotransferase (PRAT) catalyses the first committed step of de novo purine synthesis. In Phaseolus vulgaris there are three genes coding for PRAT. The three full-length sequences, which are intron-less genes, were cloned, and their expression levels were determined under conditions that affect the synthesis of purines. One of the three genes, PvPRAT3, is highly expressed in nodules and protein amount and enzymatic activity in these tissues correlate with nitrogen fixation activity. Inhibition of PvPRAT3 gene expression by RNAi-silencing and subsequent metabolomic analysis of the transformed roots shows that PvPRAT3 is essential for the synthesis of ureides in P. vulgaris nodules.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1111/pce.12743 | DOI Listing |
Purpose: The mammalian target of rapamycin (mTOR) inhibitor everolimus is US Food and Drug Administration-approved for advanced pancreatic neuroendocrine neoplasms (pNENs), yet resistance is common, necessitating the identification of resistance mechanisms for effective treatment strategies. Previous studies suggest that targeting the aberrant expression of mTOR regulators p21-activated kinase 4 (PAK4) and nicotinamide phosphoribosyl transferase (NAMPT) sensitizes pNENs to everolimus. In this study, we queried a large real-world data set of pNENs, characterizing the molecular and immune landscapes, as well as the clinical outcomes associated with aberrant PAK4 and NAMPT expression.
View Article and Find Full Text PDFFree Radic Biol Med
November 2024
Department of Nutritional Science and Food Management, Graduate Program in System Health Science and Engineering, Ewha Womans University, 52 Ewhayeodae-gil, Seodaemun-gu, Seoul 03760, Republic of Korea; Log(me) Corporation, 232 Saemunan-ro 5-gil, Jongno-gu, Seoul 03182, Republic of Korea. Electronic
Reactive oxygen species (ROS) play a vital role in cellular functions but can lead to oxidative stress and contribute to degenerative diseases when produced in excess. Maintaining redox balance is essential and can be achieved through innate defense mechanisms or external antioxidants. Superoxide dismutase (SOD) is a key enzyme that mitigates intracellular oxidative stress by converting harmful free radicals into hydrogen peroxide, which is subsequently neutralized by catalase and glutathione peroxidase.
View Article and Find Full Text PDFCancer Sci
November 2024
Division of Otolaryngology and Head and Neck Surgery, Graduate School of Medical Science, Kanazawa University, Kanazawa, Japan.
Cancer cells show a dynamic metabolic landscape, requiring a sufficient supply of nucleotides to proliferate. They are highly dependent on de novo purine biosynthetic pathways for their nucleotide requirements. Phosphoribosyl pyrophosphate amidotransferase (PPAT), catalyzing the first step of de novo purine biosynthesis, is highly expressed in various cancers.
View Article and Find Full Text PDFNucleosides Nucleotides Nucleic Acids
November 2024
Section of Infection and Immunity, Herman Ostrow School of Dentistry, Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, California, USA.
Glutamine amidotransferases (GATs) catalyze the synthesis of nucleotides, amino acids, glycoproteins and an enzyme cofactor, thus serving as key metabolic enzymes for cell proliferation. arbamoyl-phosphate synthetase, spartate transcarbamoylase, and ihydroorotase (CAD) is a multifunctional enzyme of the GAT family and catalyzes the first three steps of the pyrimidine synthesis. Following our findings that cellular GATs are involved in immune evasion during herpesvirus infection, we discovered that CAD reprograms cellular metabolism to fuel aerobic glycolysis and nucleotide synthesis deamidating RelA.
View Article and Find Full Text PDFChembiochem
April 2024
Gorlaeus Laboratories, Leiden Institute of Chemistry, Faculty of Science, Einsteinweg 55, 2333 CC, Leiden, the Netherlands.
Mono-ADP-ribosylation is a dynamic post-translational modification (PTM) with important roles in cell signalling. This modification occurs on a wide variety of amino acids, and one of the canonical modification sites within proteins is the side chain of glutamic acid. Given the transient nature of this modification (acylal linkage) and the high sensitivity of ADP-ribosylated glutamic acid, stabilized isosteres are required for structural and biochemical studies.
View Article and Find Full Text PDF