Related Experiment Video
Updated: May 28, 2026
09:45
In Vitro SUMOylation Assay to Study SUMO E3 Ligase Activity
Published on: January 29, 2018
Ribosomal protein S3 is stabilized by sumoylation
Chang-Young Jang1, Hyun-Seock Shin, Hag Dong Kim
1Laboratory of Biochemistry, School of Life Sciences and Biotechnology, and BioInstitute, Korea University, Seoul 136-701, Republic of Korea.
Biochemical and Biophysical Research Communications
|October 5, 2011
Summary
Human ribosomal protein S3 (rpS3) is modified by SUMO-1, enhancing its stability. This post-translational modification by small ubiquitin-related modifier-1 (SUMO-1) regulates rpS3 function in DNA repair.
Area of Science:
- Molecular Biology
- Biochemistry
- Genetics
Background:
- Human ribosomal protein S3 (rpS3) is a DNA repair endonuclease.
- rpS3 function is regulated by post-translational modifications like phosphorylation and methylation.
Purpose of the Study:
- To identify novel interacting partners of rpS3.
- To investigate the role of post-translational modifications in rpS3 stability and function.
Main Methods:
- Yeast-two hybrid screening to identify interacting proteins.
- Expression and analysis of rpS3 sumoylation in bacterial (Escherichia coli) and mammalian cell systems.
- Identification of sumoylation sites on rpS3.
Main Results:
- Small ubiquitin-related modifier-1 (SUMO-1) was identified as a novel interacting partner of rpS3.
- rpS3 undergoes covalent modification by SUMO-1 at Lys18, Lys214, or Lys230.
- Sumoylated rpS3 exhibited increased resistance to proteolytic degradation, indicating enhanced protein stability.
Conclusions:
- rpS3 is covalently modified by SUMO-1.
- SUMO-1 conjugation enhances rpS3 protein stability.
- This post-translational modification regulates rpS3 function, likely through increased stability.
Related Concept Videos
02:53Ribosomal RNA Synthesis
Ribosome synthesis is a highly complex and coordinated process involving more than 200 assembly factors. The synthesis and processing of ribosomal components occurs not only in the nucleolus but also in the nucleoplasm and the cytoplasm of eukaryotic cells.
Ribosome biogenesis begins with the synthesis of 5S and 45S pre-rRNAs by distinct RNA polymerases. The primary transcripts are extensively processed and modified before they are bound and folded by ribosomal proteins and assembly factors,...
Ribosome biogenesis begins with the synthesis of 5S and 45S pre-rRNAs by distinct RNA polymerases. The primary transcripts are extensively processed and modified before they are bound and folded by ribosomal proteins and assembly factors,...
02:04Covalently Linked Protein Regulators
Proteins can undergo many types of post-translational modifications, often in response to changes in their environment. These modifications play an important role in the function and stability of these proteins. Covalently linked molecules include functional groups, such as methyl, acetyl, and phosphate groups, and also small proteins, such as ubiquitin. There are around 200 different types of covalent regulators that have been identified.
These groups modify specific amino acids in a protein.
These groups modify specific amino acids in a protein.
01:29Translational Regulation
Translational regulation in prokaryotes ensures efficient protein synthesis by controlling ribosome access to mRNA. This regulation is mediated by secondary RNA structures, including translational riboswitches, RNA thermometers, and small RNAs (sRNAs), which respond to intracellular and environmental signals to modulate gene expression.Translational RiboswitchesRiboswitches in the leader region of mRNAs can regulate translation by altering the accessibility of the Shine-Dalgarno (SD) sequence,...
01:45Regulation of Nuclear Protein Sorting
Nuclear protein sorting regulates nucleus composition and gene expression, crucial for determining the fate of a eukaryotic cell. Hence, the entry and exit of molecules across the nuclear envelope is a tightly controlled process. Nuclear protein sorting can be inhibited by one of the following ways: 1) masking cargo signal sequences, 2) modifying the nuclear receptor's affinity for cargo, 3) controlling the nuclear pore size, 4) retaining the cargo during its transit to the cytosol or the...
01:23Regulation of Expression at Multiple Steps
The gene expression in cells is regulated at different stages: (i) transcription, (ii) RNA processing, (iii) RNA localization, and (iv) translation. Transcriptional regulation is mediated by regulatory proteins such as transcription factors, activators, or repressors—these control gene expression by initiating or inhibiting the transcription of genes. Once a precursor or pre-mRNA is produced, it undergoes post-transcriptional modification, including 5' capping, splicing, and the addition of a...
01:26Protein Modifications in the RER
Modification of secretory and transmembrane proteins entering the rough ER begins in the ER lumen. These modifications aid in protein folding and stabilize the acquired tertiary structure. Protein modifications in the rough ER co-occur at different stages of protein folding.
Broadly, these modifications can be categorized into four main categories — glycosylation, formation of disulfide bonds, assembly of protein subunits, and specific proteolytic cleavages like removal of signal sequences.
Broadly, these modifications can be categorized into four main categories — glycosylation, formation of disulfide bonds, assembly of protein subunits, and specific proteolytic cleavages like removal of signal sequences.