Related Experiment Video
Updated: Jun 26, 2026
11:12
Determination of the Optimal Chromosomal Locations for a DNA Element in Escherichia coli Using a Novel Transposon-mediated Approach
Published on: September 11, 2017
7.6K
IS481EU Shows a New Connection between Eukaryotic and Prokaryotic DNA Transposons
1Genetic Information Research Institute, Cupertino, CA 95014, USA.
Biology
|March 29, 2023
Summary
A new group of eukaryotic DNA transposons, IS481EU, was discovered in parabasalids. These transposons exhibit unique target site duplication lengths and phylogenetic links to prokaryotic IS481 elements.
Area of Science:
- Genetics
- Molecular Biology
- Bioinformatics
Background:
- The DDD/E transposase gene is crucial for DNA transposition across all life domains.
- Eukaryotic DNA transposons often share similarities with prokaryotic insertion sequences (ISs).
- IS481-like DNA transposons were previously suggested in *Trichomonas vaginalis*.
Purpose of the Study:
- To identify and characterize IS481-like eukaryotic DNA transposons.
- To investigate the phylogenetic relationships of these elements with known transposons.
- To establish a new superfamily of eukaryotic DNA transposons.
Main Methods:
- Bioinformatic survey of eukaryotic genomes.
- Sequence analysis of identified transposon candidates.
- Phylogenetic analysis using protein sequences.
Main Results:
- Discovery of IS481EU, a novel group of eukaryotic IS481-like DNA transposons in parabasalids, including *T. vaginalis*.
- IS481EU elements display variable target site duplication (TSD) lengths (approx. 4, 15, or 25 bps), even within the same family.
- Phylogenetic analysis shows IS481EU is closely related to prokaryotic IS481 family members and distinct from other eukaryotic DNA transposons like Ginger1 and Ginger2.
Conclusions:
- IS481EU represents a new superfamily of eukaryotic DNA transposons.
- Unique protein features and TSD length distribution distinguish IS481EU.
- This discovery expands our understanding of transposon diversity in eukaryotes.
Related Concept Videos
02:13Overview of Transposition and Recombination
Transposons make up a significant part of genomes of various organisms. Therefore, it is believed that transposition played a major evolutionary role in speciation by changing genome sizes and modifying gene expression patterns. For example, in bacteria, transposition can lead to conferring antibiotic resistance. Movement of transposable elements within the genetic pool of pathogenic bacteria can aid in transfer of antibiotic-resistant genetic elements. In eukaryotes, transposons can carry out...
02:57DNA-only Transposons
DNA-only transposons are called autonomous transposons since they code for the enzyme transposase that is required for the transposition mechanism. Insertion of transposons can alter gene functions in multiple ways. They can mutate the gene, alter gene expression by introducing a novel promoter or insulator sequence, introduce new splice sites, and change the mRNA transcripts produced, or remodel chromatin structure.
The donor site from where the transposon is excised is either degraded or...
The donor site from where the transposon is excised is either degraded or...
03:08LTR Retrotransposons
LTR retrotransposons are class I transposable elements with long terminal repeats flanking an internal coding region. These elements are less abundant in mammals compared to other class I transposable elements. About 8 percent of human genomic DNA comprises LTR retrotransposons. Some of the common examples of LTR retrotransposons are Ty elements in yeast and Copia elements in Drosophila.
The internal coding region of LTR retrotransposons and their mechanism of transposition closely resembles a...
The internal coding region of LTR retrotransposons and their mechanism of transposition closely resembles a...
03:18Non-LTR Retrotransposons
As the name suggests, non-LTR retrotransposons lack the long terminal repeats characteristic of the LTR retrotransposons. Additionally, both LTR and non-LTR retrotransposons use distinct mechanisms of mobilization. Non-LTR retrotransposons are further divided into two classes - Long interspersed nuclear elements (LINEs) and short interspersed nuclear elements (SINEs), both of which occur abundantly in most mammals, including humans. Some of the active non-LTR retrotransposons in humans are L1...
02:57piRNA - Piwi-interacting RNAs
PIWI-interacting RNAs, or piRNAs, are the most abundant short non-coding RNAs. More than 20,000 genes have been found in humans that code for piRNAs while only 2000 genes have been found for miRNAs. piRNAs can act at the transcriptional and post-transcriptional levels and have a vital role in silencing transposable elements present in germ cells. They are also involved in epigenetic silencing and activation. Previously, they were thought to function only in germ cells but new evidence suggests...
01:24Transposons
Transposons, or "jumping genes," are small mobile genetic elements (MGEs) that range from 700 to 40,000 base pairs in length. They are found in all organisms and can move within the same chromosome or transfer to different chromosomes. In some cases, transposons can also jump between different host DNA molecules, such as plasmids or viruses, contributing to genetic variability.Barbara McClintock first discovered these mobile genetic elements in the 1940s while studying maize genetics, and she...