Video Experimental Relacionado
Updated: Jun 4, 2026
11:34
Exploring Sequence Space to Identify Binding Sites for Regulatory RNA-Binding Proteins
Published on: August 9, 2019
HSPC117 es la subunidad esencial de un complejo de ligasa de empalme de tRNA humano
Johannes Popow1, Markus Englert, Stefan Weitzer
1Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), A-1030 Vienna, Austria.
Science (New York, N.Y.)
|February 12, 2011
Resumen
Los investigadores identificaron HSPC117 (familia RtcB) como una enzima clave en el empalme del ARN de transferencia de precursores (ARNt). El agotamiento de esta proteína detiene la maduración del tRNA, revelando su papel esencial en el procesamiento del ARN en los organismos.
Área de la Ciencia:
- Biología Molecular Biología Molecular
- La bioquímica es la bioquímica.
- Genética La genética.
Sus antecedentes:
- El empalme del ARN de transferencia (ARNt) es crucial para generar moléculas funcionales de ARNt.
- El splicing de pre-tRNA de mamíferos implica la eliminación de intrones y la posterior ligadura de exones.
- La enzima responsable del segundo paso, la tRNA ligasa, ha permanecido elusiva.
Objetivo del estudio:
- Para identificar la subunidad esencial del complejo de tRNA ligasa de mamíferos.
- Para aclarar el papel de las proteínas identificadas en la maduración del pre-ARNt.
- Para investigar la conservación evolutiva y la función de la familia de las tRNA ligasas.
Principales métodos:
- Purificación guiada por actividad de la tRNA ligasa a partir de extractos de células HeLa.
- Identificación de los componentes de las proteínas mediante ensayos bioquímicos.
- Interferencia de ARN (RNAi) para agotar las proteínas diana y evaluar el impacto funcional.
- Ensayos in vitro e in vivo para la maduración del pre-ARNt.
Principales resultados:
- HSPC117, un miembro de la familia UPF0027 (RtcB), fue identificado como la subunidad esencial del complejo de tRNA ligasa.
- El agotamiento de HSPC117 utilizando interferencia de ARN inhibió significativamente el empalme y la maduración pre-tRNA.
- Esta inhibición se observó tanto in vitro como en células vivas, lo que confirma el papel crítico de HSPC117.
Conclusiones:
- HSPC117 es el componente indispensable del complejo de la tRNA ligasa en los mamíferos.
- El estudio proporciona la primera evidencia directa de que las proteínas de la familia HSPC117/RtcB actúan como ligasas de tRNA.
- La conservación de alta secuencia sugiere una función de ARN ligasa conservada para esta familia de proteínas en diversos organismos.
Videos de Conceptos Relacionados
01:32RNA Splicing
Splicing is the process by which eukaryotic RNA is edited before its translation into protein. The RNA strand transcribed from eukaryotic DNA is called the primary transcript. The primary transcripts that become mRNAs are called precursor messenger RNAs (pre-mRNAs). Eukaryotic pre-mRNA contains alternating sequences of exons and introns. Exons are nucleotide sequences that code for proteins, whereas introns are the non-coding regions. In RNA splicing, introns are removed and exons are bonded...
01:32RNA Splicing
Splicing is the process by which eukaryotic RNA is edited before its translation into protein. The RNA strand transcribed from eukaryotic DNA is called the primary transcript. The primary transcripts that become mRNAs are called precursor messenger RNAs (pre-mRNAs). Eukaryotic pre-mRNA contains alternating sequences of exons and introns. Exons are nucleotide sequences that code for proteins, whereas introns are the non-coding regions. In RNA splicing, introns are removed and exons are bonded...
01:28Protein Translocation Machinery on the ER Membrane
The translocon complex situated on the ER membrane is the main gateway for the protein secretory pathway. It facilitates the transport of nascent peptides into the ER lumen and their insertion into the ER membrane.
Sec61 protein conducting channel
In eukaryotes, the translocon complex comprises a core heterotrimeric translocator channel called the Sec61 complex. This channel includes three transmembrane proteins, Sec61α, Sec61β, and Sec61γ, and is the largest subunit of the translocon complex.
Sec61 protein conducting channel
In eukaryotes, the translocon complex comprises a core heterotrimeric translocator channel called the Sec61 complex. This channel includes three transmembrane proteins, Sec61α, Sec61β, and Sec61γ, and is the largest subunit of the translocon complex.
01:20Cotranslational Protein Translocation
Translocation of proteins across membranes is an ancient process that occurs even in bacteria and archaebacteria. In fact, the components of the translocation machinery are still conserved between prokaryotes and eukaryotes.
Sec61 channel partners for cotranslational translocation
During cotranslational translocation, the Sec61 channel partners with the signal recognition particle (SRP), the signal recognition particle receptor (SR), and the ribosomes to transport the nascent polypeptide chain...
Sec61 channel partners for cotranslational translocation
During cotranslational translocation, the Sec61 channel partners with the signal recognition particle (SRP), the signal recognition particle receptor (SR), and the ribosomes to transport the nascent polypeptide chain...
01:57Protein Complexes with Interchangeable Parts
Groups of proteins may form a complex where each protein in this complex has a different role in the overall execution of the complex’s function. Often some of the proteins in the complex can be replaced by a closely related variant to give a complex that contains many of the same components yet is functionally distinct.
The SCF ubiquitin ligase is a protein complex of five individual proteins. This complex attaches ubiquitin to other target proteins to mark them for degradation. In order to...
The SCF ubiquitin ligase is a protein complex of five individual proteins. This complex attaches ubiquitin to other target proteins to mark them for degradation. In order to...
01:57Protein Complexes with Interchangeable Parts
Groups of proteins may form a complex where each protein in this complex has a different role in the overall execution of the complex’s function. Often some of the proteins in the complex can be replaced by a closely related variant to give a complex that contains many of the same components yet is functionally distinct.
The SCF ubiquitin ligase is a protein complex of five individual proteins. This complex attaches ubiquitin to other target proteins to mark them for degradation. In order to...
The SCF ubiquitin ligase is a protein complex of five individual proteins. This complex attaches ubiquitin to other target proteins to mark them for degradation. In order to...