These tiny subnuclear bodies typically measure 360 nanometers in diameter. They are composed of a long noncoding RNA (lncRNA) molecule called NEAT1, which serves as the seed. Proteins that bind to NEAT1 accumulate, self-associate, and recruit other proteins, forming a mature paraspeckle.
When a cell is stressed, various triggers can cause it to increase the production of the lncRNA NEAT1, leading to the formation of more paraspeckles. These bodies can grow to up to 2 micrometers in length, changing from a spherical shape to oblong and sometimes branched structures. They trap various proteins and mRNAs, hindering their function and thereby affecting the cell’s continued response to stress.
|1||As they accumulate proteins and RNAs, paraspeckles can become linked together, growing bigger, oblong, and sometimes branched.|
|2||Greater abundance of NEAT1 leads to more paraspeckles.|
|3||Specific messenger RNAs become trapped in paraspeckles and cannot reach the cytoplasm for translation.|
|4||Paraspeckles act as a sponge, soaking up the proteins from the nucleoplasm.|
|5||Paraspeckles trap gene-regulating proteins, depleting them from target sites on the genome and thereby altering transcription.|
Read the full story.