Video Experimental Relacionado
Updated: Sep 9, 2025

04:04
Real-Time Quantification of the Effects of IS200/IS605 Family-Associated TnpB on Transposon Activity
Published on: January 20, 2023
2.5K
La transposición dirigida por ARN guía de novo con proteínas de la familia TnpB revela características de sistemas
bioRxiv : the preprint server for biology
|September 5, 2025
Resumen
Diseñamos nuevos sistemas de integración de ADN guiados por ARN utilizando proteínas TnpB reutilizadas. Estos sistemas compactos de transposones asociados a CRISPR (CAST) mejoran la precisión y la eficiencia en la ingeniería genómica.
Área de la Ciencia:
- Biología molecular
- Ingeniería genómica
- Tecnología CRISPR
Sus antecedentes:
- Los transposones asociados a CRISPR (CAST) permiten la integración programable del ADN.
- Los sistemas CAST existentes utilizan efectores Cas12k derivados de las nucleasas TnpB.
- Se necesita más ingeniería para optimizar el rendimiento y la especificidad del sistema CAST.
Objetivo del estudio:
- Diseñar de nuevo sistemas de transposición guiados por ARN utilizando proteínas TnpB reutilizadas.
- Mejorar la eficiencia, especificidad y programabilidad de la integración del ADN.
- Explorar mutaciones para mejorar la actividad en el sitio y reducir la orientación fuera del sitio en los sistemas CAST.
Principales métodos:
- Reutilización de las proteínas de la familia TnpB muertas por nucleasa como efectores guiados por ARN.
- Desarrollo de sistemas compactos de transposición guiados por ARN de novo.
- Introducción de mutaciones en la interfaz TniQ-TnsC en los sistemas Cas12k CAST.
Principales resultados:
- Los sistemas diseñados demostraron una alta eficiencia, la inserción de ADN dirigida por ARN con control de orientación preservado y inmunidad objetivo.
- Se observó una reducción de la orientación fuera del sitio y la liberación de un requisito de factor de acogida.
- Las mutaciones en la interfaz TniQ-TnsC atenuaron selectivamente las inserciones fuera del sitio mientras aumentaban la actividad en el sitio.
- Emparejado con un dominio de exonucleasa, los sistemas median la transposición de corte y pegado.
Conclusiones:
- Los derivados de TnpB diseñados exhiben características novedosas para mejorar la ingeniería genómica.
- Los sistemas Cas12k CAST pueden perfeccionarse para obtener un alto rendimiento y especificidad.
- Estos avances ofrecen nuevas vías para aplicaciones precisas y eficientes de edición del genoma.
Videos de Conceptos Relacionados
Overview of Transposition and Recombination
16.1K
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...
16.1K
DNA-only Transposons
14.8K
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...
14.8K
LTR Retrotransposons
17.9K
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...
17.9K
Conservative Site-specific Recombination and Phase Variation
6.1K
Because the DNA segments are cut and reorganized in a direction-specific manner, site-specific recombination has emerged as an efficient genetic engineering technique. Flippase and Cyclization recombinases or Flp and Cre, respectively, are two members of the tyrosine recombinase family derived from bacteriophages, that are used to mediate site-specific DNA insertions, deletions, and targeted expression of proteins in mammalian cell lines.
The recognition sites for Cre recombinase called LoxP...
The recognition sites for Cre recombinase called LoxP...
6.1K
piRNA - Piwi-interacting RNAs
7.0K
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...
7.0K
Bacterial RNA Polymerase
30.3K
Unlike eukaryotes, bacteria use a single RNA Polymerase (RNAP) to transcribe all genes. The different subunits of bacterial RNAPhave distinct functions. The multisubunit structure of the bacterial RNAP helps the enzyme to maintain catalytic function, facilitate assembly, interact with DNA and RNA, and self-regulate its activity.
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
30.3K

