RNA Splicing

Summary

The video explains RNA splicing, a crucial process in gene expression. It describes how non-coding regions (introns) are removed from the RNA transcript, leaving only the coding regions (exons). This editing is carried out by the spliceosome, a molecular machine formed by helper proteins and small nuclear ribonucleoproteins. The spliceosome cuts the RNA, removes introns, and joins exons together. This process occurs repeatedly along the RNA transcript, ensuring that the final, edited RNA contains the complete instructions for protein synthesis.

Takeaways

• 😀 DNA is transcribed into RNA, which undergoes editing to remove non-coding regions called introns.
• 😀 Introns, shown in green, are non-coding regions that need to be removed during RNA processing.
• 😀 The RNA splicing process involves the removal of introns, leaving only protein-coding exons, shown in yellow.
• 😀 RNA splicing begins with the assembly of helper proteins at the intron/exon borders.
• 😀 These splicing factors guide small nuclear ribonucleoproteins (snRNPs) to form a complex called the spliceosome.
• 😀 The spliceosome is responsible for bringing the exons close together, preparing them for cutting.
• 😀 One end of the intron is cut and folded into a loop before being removed.
• 😀 The spliceosome cuts the RNA to release the intron loop and join the two exons together.
• 😀 Once splicing is complete, the edited RNA and intron are released, and the spliceosome disassembles.
• 😀 This process of splicing is repeated for every intron in the RNA until all introns are removed, leaving the protein-coding exons.
• 😀 Multiple spliceosomes work in parallel along the RNA to remove different introns, ultimately ensuring the correct protein instructions are left.

Q & A

What is RNA splicing?

RNA splicing is the process by which non-coding regions, or introns, are removed from the RNA transcript, leaving only the protein-coding regions, called exons.

What are introns and exons?

Introns are non-coding regions of RNA that are removed during splicing, while exons are the protein-coding regions that remain after splicing.

What is the role of splicing factors in RNA splicing?

Splicing factors are proteins that assemble at the intron/exon borders and act as beacons to guide small nuclear ribonucleoproteins (snRNPs) to form the spliceosome.

What is the spliceosome?

The spliceosome is a molecular machine made up of proteins and small nuclear RNA (snRNA) that facilitates the removal of introns and the joining of exons during RNA splicing.

How does the spliceosome function during RNA splicing?

The spliceosome brings the exons on either side of the intron close together, cuts one end of the intron, folds it into a loop, and then cuts the RNA to release the loop and join the exons.

What happens to the intron during RNA splicing?

During splicing, the intron is cut, folded back to form a loop, and then released from the RNA molecule after the exons are joined together.

How many introns are removed in this example of RNA splicing?

In this example, three introns are removed from the RNA molecule, leaving only the exons that contain the instructions for a protein.

What happens after the spliceosome completes its task?

After the spliceosome removes an intron and joins the exons, the spliceosome disassembles and the edited RNA is released.

How many spliceosomes are involved in the RNA splicing process?

Numerous spliceosomes are involved in the RNA splicing process. Each spliceosome removes one intron at a time, releasing a loop before disassembling.

Why is RNA splicing important?

RNA splicing is crucial because it removes non-coding introns and ensures that the RNA transcript contains only the necessary exons that encode for a protein, allowing proper gene expression.