Geeniilmentymää

Geeniilmentymää refers to the process by which the information encoded in a gene is used in the synthesis of a functional gene product. This product is usually a protein, but functional RNAs such as ribosomal RNA (rRNA) and transfer RNA (tRNA) are also products of gene expression. The central dogma of molecular biology describes the flow of genetic information from DNA to RNA to protein.

The process begins with transcription, where a segment of DNA is copied into a messenger RNA (mRNA) molecule. This mRNA molecule then carries the genetic code from the DNA in the nucleus to the ribosomes in the cytoplasm. At the ribosome, the process of translation occurs. During translation, the sequence of nucleotides in the mRNA is read in codons, which are three-nucleotide units. Each codon specifies a particular amino acid, and these amino acids are linked together in a specific order to form a polypeptide chain. This polypeptide chain then folds into a functional protein.

Regulation of gene expression is crucial for cellular function and development. Cells can control which genes are transcribed and translated, and at what levels, allowing them to respond to environmental changes and specialize for particular roles. This regulation can occur at various stages, including DNA accessibility, transcription initiation, RNA processing, translation, and protein modification. Errors in gene expression can lead to diseases, highlighting the importance of this fundamental biological process.