ribonukleinsyre

Ribonukleinsyre, commonly known as RNA, is a nucleic acid essential for various biological functions in all living organisms. It is a single-stranded molecule, unlike its counterpart deoxyribonucleic acid (DNA), which is typically double-stranded. The building blocks of RNA are nucleotides, each composed of a ribose sugar, a phosphate group, and one of four nitrogenous bases: adenine (A), guanine (G), cytosine (C), and uracil (U). Uracil replaces thymine, which is found in DNA.

RNA plays a crucial role in protein synthesis. Messenger RNA (mRNA) carries genetic information transcribed from DNA in the nucleus to the ribosomes in the cytoplasm, where protein synthesis occurs. Transfer RNA (tRNA) molecules bring specific amino acids to the ribosome, matching them to the mRNA sequence to build the polypeptide chain. Ribosomal RNA (rRNA) is a structural component of ribosomes, catalyzing peptide bond formation.

Beyond protein synthesis, RNA has other vital roles. Small nuclear RNA (snRNA) is involved in RNA splicing, a process that removes non-coding regions from pre-mRNA. MicroRNA (miRNA) and small interfering RNA (siRNA) are regulatory RNAs that can silence gene expression by degrading target mRNA molecules or inhibiting their translation. Various types of RNA, including ribozymes, also possess catalytic activity, performing enzymatic functions. The versatility and diverse functions of RNA highlight its fundamental importance in cellular processes.