The mechanism of selenocysteine incorporation in eukaryotes has been assumed for almost a decade to be inherently different from that in prokaryotes, due to differences in the architecture of selenoprotein mRNAs in the two kingdoms. After extensive efforts in a number of laboratories spanning the same time frame, some of the essential differences between these mechanisms are finally being revealed, through identification of the factors catalyzing cotranslational selenocysteine insertion in eukaryotes. A single factor in prokaryotes recognizes both the selenoprotein mRNA, via sequences in the coding region, and the unique selenocysteyl-tRNA, via both its secondary structure and amino acid. The corresponding functions in eukaryotes are conferred by two distinct but interacting factors, one recognizing the mRNA, via structures in the 3' untranslated region, and the second recognizing the tRNA. Now, with these factors in hand, crucial questions about the mechanistic details and efficiency of this intriguing process can begin to be addressed.

Download full-text PDF

Source
http://dx.doi.org/10.1002/biof.5520140104DOI Listing

Publication Analysis

Top Keywords

selenocysteine incorporation
8
incorporation directed
4
directed 3'utr
4
3'utr characterization
4
characterization eukaryotic
4
eukaryotic efsec
4
efsec mechanistic
4
mechanistic implications
4
implications mechanism
4
mechanism selenocysteine
4

Similar Publications

Selenium promotes neural development through the regulation of GPX4 and SEPP1 in an iPSC-derived neuronal model.

Biomaterials

May 2025

State Key Laboratory of Bioactive Molecules and Druggability Assessment, Guangdong Basic Research Center of Excellence for Natural Bioactive Molecules and Discovery of Innovative Drugs, Key Laboratory of CNS Regeneration (Ministry of Education), Guangdong Key Laboratory of Non-Human Primate Research, GHM Institute of CNS Regeneration, Department of Chemistry, Jinan University, Guangzhou, 510632, China; Department of Psychiatry, The First Affiliated Hospital, Jinan University, Guangzhou, 510632, China; Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, 226019, China; Department of Neurology, Hainan General Hospital (Hainan Affiliated Hospital of Hainan Medical University), Haikou, 570100, China. Electronic address:

Selenium (Se) is incorporated into selenoproteins in the form of selenocysteine, which has biological functions associated with neural development. Unfortunately, the specific roles and mechanisms of selenoproteins at different stages of neuronal development are still unclear. Therefore, in this study, we successfully established a neuronal model derived from induced pluripotent stem cells (iPSC-iNeuron) and used Se nanoparticles (SeNPs@LNT) with high bioavailability to intervene at different stages of neural development in iPSC-iNeuron model.

View Article and Find Full Text PDF

PRDX6 dictates ferroptosis sensitivity by directing cellular selenium utilization.

Mol Cell

December 2024

Institute of Metabolism and Cell Death, Molecular Targets and Therapeutics Center, Helmholtz Munich, Neuherberg, Bavaria 85764, Germany. Electronic address:

Selenium-dependent glutathione peroxidase 4 (GPX4) is the guardian of ferroptosis, preventing unrestrained (phospho)lipid peroxidation by reducing phospholipid hydroperoxides (PLOOH). However, the contribution of other phospholipid peroxidases in ferroptosis protection remains unclear. We show that cells lacking GPX4 still exhibit substantial PLOOH-reducing capacity, suggesting a contribution of alternative PLOOH peroxidases.

View Article and Find Full Text PDF

Intervertebral disc degeneration (IVDD) is a prevalent musculoskeletal disorder that involves the excessive accumulation of reactive oxygen species (ROS), resulting in mitochondrial dysfunction and matrix metabolism imbalance in nucleus pulposus cells (NPCs). Selenium, an indispensable trace element, plays a crucial role in maintaining mitochondrial redox homeostasis by being incorporated into antioxidant selenoproteins as selenocysteine. In this study, we employed a straightforward synthesis method to produce selenium nanoparticles (SeNPs) with consistent size and distribution, and evaluated their potential protective effects in ameliorating IVDD.

View Article and Find Full Text PDF
Article Synopsis
  • The incorporation of selenocysteine (Sec) into the genetic code has led to the creation of a specialized group of proteins, known as the selenoproteome, across all life forms.* -
  • In humans, the enzyme O-phosphoseryl-tRNASec selenium transferase (SepSecS) has a unique structure that limits its ability to bind more than two tRNASec molecules, due to a specific acidic α-helical extension.* -
  • Research finds that the tRNA-binding mechanisms of SepSecS vary across species, with significant differences between mammals and archaea, indicating that the ability to regulate selenoprotein synthesis has evolved differently in these groups.*
View Article and Find Full Text PDF

Overcoming Challenges with Biochemical Studies of Selenocysteine and Selenoproteins.

Int J Mol Sci

September 2024

Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602, USA.

Selenocysteine (Sec) is an essential amino acid that distinguishes itself from cysteine by a selenium atom in place of a sulfur atom. This single change imparts distinct chemical properties to Sec which are crucial for selenoprotein (Sec-containing protein) function. These properties include a lower p, enhanced nucleophilicity, and reversible oxidation.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!