RNA Splicing Process

Overview

• DNA to RNA Transcription: During transcription, DNA is converted into RNA.
• Need for Editing: RNA transcribed includes both coding (exons) and non-coding regions (introns).

Splicing

• Purpose: Remove non-coding regions (introns) to leave only the coding exons.
• Process Name: This editing process is called splicing.

Mechanism of Splicing

1. Assembly of Helper Proteins

   • Helper proteins gather at intron/exon borders.
   • These are known as splicing factors.
   • They act as beacons for small nuclear ribo proteins.

2. Formation of Spliceosome

   • Splicing factors guide the formation of the spliceosome.
   • The spliceosome is the complex that performs the splicing.

3. Cutting and Loop Formation

   • Spliceosome brings exons close together.
   • One end of an intron is cut and folded to form a loop.

4. Joining and Release

   • The spliceosome cuts the RNA to release the loop.
   • Exons are joined together.
   • Edited RNA and the looped intron are released.
   • The spliceosome disassembles.

Multiple Spliceosomes

• Numerous spliceosomes assemble along the RNA.
• Each spliceosome removes one intron.
• Example: Three introns are removed in the animation.

Conclusion

• Result: Leads to a complete set of instructions for protein synthesis by removing introns and joining exons.