PQBP1 : polyglutamine binding protein 1

Description

The PQBP1 (polyglutamine binding protein 1) is a protein-coding gene located on chromosome X.

The PQBP1 gene provides instructions for making a protein called polyglutamine-binding protein 1. This protein attaches (binds) to stretches of multiple copies of a protein building block (amino acid) called glutamine in certain other proteins.While the specific function of polyglutamine-binding protein 1 is not well understood, it is believed to play a role in processing and transporting RNA, a chemical cousin of DNA that serves as the genetic blueprint for the production of proteins.In nerve cells (neurons) such as those in the brain, polyglutamine-binding protein 1 is found in structures called RNA granules. These granules allow the transport and storage of RNA within the cell. The RNA is held within the granules until the genetic information it carries is translated to produce proteins or until cellular signals or environmental factors trigger the RNA to be degraded. Through these mechanisms, polyglutamine-binding protein 1 is thought to help control the way genetic information is used (gene expression) in neurons. This control is important for normal brain development.

PQBP1 is an intrinsically disordered protein that acts as a scaffold and plays roles in various cellular processes, including pre-mRNA splicing, transcription regulation, innate immunity, and neuron development. It interacts with splicing factors through its disordered region, regulating alternative splicing of target pre-mRNAs. PQBP1 can suppress the transactivation of the DRD1 gene by POU3F2 in a POU3F2-dependent manner and can activate transcription directly or via association with the transcription machinery. It may be involved in cell death induced by mutant ATXN1, and its interaction with this mutant decreases the levels of phosphorylated RNA polymerase II large subunit. PQBP1 contributes to the formation of cytoplasmic stress granules, potentially by participating in the transport of neuronal RNA granules. It acts as an innate immune sensor against retroviral infections, such as HIV, by detecting reverse-transcribed DNA in the cytosol. PQBP1 directly binds retroviral reverse-transcribed DNA and interacts with CGAS, activating the cGAS-STING signaling pathway, ultimately triggering type-I interferon production.

PQBP1 is also known as MRX2, MRX55, MRXS3, MRXS8, NPW38, RENS1, SHS.

Associated Diseases

• Hamel cerebro-palato-cardiac syndrome
• Renpenning syndrome
• X-linked intellectual disability, Porteous type
• X-linked intellectual disability, Sutherland-Haan type
• X-linked intellectual disability, Golabi-Ito-Hall type
• Coloboma