RNApólímerasi

RNApólímerasi, also known as RNA polymerase, is a crucial enzyme responsible for synthesizing RNA molecules from a DNA template. This process, called transcription, is fundamental to gene expression in all living organisms. RNA polymerase reads the DNA sequence and uses it as a blueprint to assemble a complementary RNA strand. The enzyme plays a vital role in copying genetic information from DNA into messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA), each serving distinct functions in the cell.

There are different types of RNA polymerase in eukaryotes, with RNA polymerase II being the primary enzyme responsible for transcribing protein-coding genes into mRNA. Prokaryotes typically have a single type of RNA polymerase that handles all RNA synthesis. The enzyme works by unwinding the DNA double helix locally, allowing it to access the nucleotide bases. It then adds RNA nucleotides one by one, following the base-pairing rules (A with U, and G with C), until it reaches a termination signal on the DNA. This synthesized RNA molecule then plays a direct or indirect role in protein production or other cellular processes. The fidelity of RNA synthesis is critical for cellular function, and RNA polymerase incorporates proofreading mechanisms to minimize errors during transcription.