RNAmolekyyliä

RNAmolekyyliä, often referred to as RNA, is a crucial nucleic acid involved in various biological processes. It is a polymer composed of a chain of nucleotide monomers. Each nucleotide consists of a ribose sugar, a phosphate group, and one of four nitrogenous bases: adenine (A), guanine (G), cytosine (C), or uracil (U). Unlike DNA, RNA typically exists as a single-stranded molecule, though it can fold upon itself to form complex three-dimensional structures.

The primary function of RNA is to facilitate the expression of genetic information encoded in DNA. Messenger RNA (mRNA) carries the genetic code from DNA in the nucleus to ribosomes in the cytoplasm, where it serves as a template for protein synthesis. Transfer RNA (tRNA) molecules are responsible for bringing specific amino acids to the ribosome during translation, matching them to the codons on the mRNA. Ribosomal RNA (rRNA) is a structural and catalytic component of ribosomes, playing a key role in protein assembly.

Beyond protein synthesis, RNA molecules also participate in gene regulation, acting as microRNAs (miRNAs) and small interfering RNAs (siRNAs) to modulate gene expression. Some RNA molecules possess catalytic activity, known as ribozymes, and are involved in various biochemical reactions. The versatility of RNA highlights its fundamental importance in cellular life.