Paraspeckle

Nuclear bodies involved in RNA processing

Paraspeckles in HeLa cells visualized using fluorescence microscopy.

Paraspeckles are subnuclear structures found in the interchromatin space of mammalian cell nuclei. They are involved in the regulation of gene expression and are associated with the retention of certain RNA molecules within the nucleus. Paraspeckles are dynamic structures that form in response to cellular stress and are implicated in various cellular processes.

Structure

Paraspeckles are composed of a core of long non-coding RNA (lncRNA) known as NEAT1 and a variety of RNA-binding proteins. The NEAT1 lncRNA serves as a scaffold for the assembly of paraspeckle proteins, including PSPC1, NONO, and SFPQ. These proteins are essential for the structural integrity and function of paraspeckles.

Function

Paraspeckles play a crucial role in the post-transcriptional regulation of gene expression. They are involved in the nuclear retention of hyper-edited RNA transcripts, preventing their export to the cytoplasm. This retention mechanism is important for the regulation of gene expression in response to cellular stress and other stimuli.

Formation

Diagram illustrating the formation and function of paraspeckles.

Paraspeckles form in the nucleus during the transcription of NEAT1 lncRNA. The assembly of paraspeckles is a highly regulated process that involves the recruitment of specific RNA-binding proteins to the NEAT1 RNA scaffold. The formation of paraspeckles is influenced by various cellular conditions, including stress and differentiation signals.

Role in Disease

Dysregulation of paraspeckle formation and function has been implicated in several diseases, including cancer and neurodegenerative disorders. Alterations in the expression of NEAT1 and paraspeckle-associated proteins can lead to changes in gene expression patterns, contributing to disease pathogenesis.

Research Techniques

The study of paraspeckles involves various molecular biology techniques, including fluorescence microscopy, RNA sequencing, and chromatin immunoprecipitation. These techniques allow researchers to investigate the composition, dynamics, and function of paraspeckles in different cellular contexts.

Related pages

• Nuclear body
• Long non-coding RNA
• RNA-binding protein