ABCE1 - ATP Binding Cassette Transporter E | Elisa - Clia - Antibody - Protein

Background

ABCE1, also known as the ATP-binding cassette protein E1 or RNase L inhibitor (RLI), is a unique member of the ATP-binding cassette (ABC) transporter superfamily. Unlike most ABC transporters, which are involved in the translocation of various substrates across membranes, ABCE1 primarily functions in the regulation of RNA processing and translation. It is highly conserved across different species, highlighting its fundamental biological importance.ABCE1 works by inhibiting the activity of ribonuclease L, thereby opposing the antiviral properties of ribonuclease L and enabling the virus to synthesize viral proteins. Additionally, ABCE1 has been implicated in influencing tumor cell proliferation

Protein Structure

ABCE1 is characterized by its unique structure:

• Two Nucleotide Binding Domains (NBDs): These domains bind and hydrolyze ATP, which is crucial for the protein's function.
• Iron-Sulfur Clusters: ABCE1 contains iron-sulfur (Fe-S) clusters, which are critical for its stability and function. These clusters are involved in protein-protein interactions and the regulation of its ATPase activity.

Unlike other ABC transporters, ABCE1 lacks the transmembrane domains typically associated with substrate transport across cellular membranes.

Classification and Subtypes

ABCE1 is the only member of the ABC subfamily E and does not have subtypes. Its unique functions distinguish it from other ABC transporters.

Function and Biological Significance

ABCE1 is involved in several critical cellular processes:

1. Inhibition of RNase L: ABCE1 inhibits RNase L, an enzyme involved in the antiviral response. By inhibiting RNase L, ABCE1 helps regulate the degradation of RNA during viral infections and maintains cellular RNA integrity.
2. Regulation of Translation: ABCE1 plays a crucial role in ribosome assembly and recycling. It interacts with translation initiation and termination factors, facilitating the proper assembly of the translation machinery and efficient recycling of ribosomes after protein synthesis.
3. RNA Interference (RNAi): ABCE1 is implicated in the RNAi pathway, influencing gene silencing mechanisms by interacting with components of the RNA-induced silencing complex (RISC).

Interactions

ABCE1 interacts with various proteins and RNA molecules:

1. RNase L: Directly inhibits RNase L activity, preventing excessive RNA degradation.
2. Translation Factors: Interacts with eukaryotic initiation factors (eIFs) and other components of the translation machinery to regulate protein synthesis.
3. Iron-Sulfur Cluster-Containing Proteins: Associates with proteins containing Fe-S clusters, which are essential for its stability and function.

Clinical Issues

Dysfunction or dysregulation of ABCE1 can lead to several clinical implications:

1. Viral Infections: Given its role in inhibiting RNase L, alterations in ABCE1 function can affect the antiviral response, potentially impacting the progression and severity of viral infections.
2. Cancer: ABCE1 has been implicated in cancer biology, where its role in translation regulation and ribosome biogenesis can influence cell proliferation and tumor growth.
3. Neurodegenerative Diseases: Mutations or malfunctions in ABCE1 may affect protein synthesis and RNA stability, contributing to the pathogenesis of neurodegenerative diseases.

Summary

ABCE1 is a unique ATP-binding cassette transporter that plays critical roles in RNA processing, translation regulation, and antiviral defense mechanisms. It is distinguished by its lack of transmembrane domains and the presence of iron-sulfur clusters, which are essential for its function. ABCE1's interactions with RNase L, translation factors, and RNA molecules underscore its importance in maintaining cellular homeostasis. Dysregulation of ABCE1 can have significant clinical consequences, including impacts on viral infections, cancer progression, and neurodegenerative diseases, highlighting its essential role in cellular physiology.