Which type of RNA is primarily involved in the synthesis of proteins?

Messenger RNA (mRNA) plays a crucial role in the synthesis of proteins by acting as a template for translation. During the process of transcription, a complementary strand of mRNA is synthesized from a DNA template, carrying the genetic instructions encoded in the DNA to the ribosomes, the sites of protein synthesis in the cell.

Once the mRNA is produced, it undergoes several modifications and then exits the nucleus into the cytoplasm, where it serves as the blueprint for building proteins. Ribosomes read the sequence of nucleotides in the mRNA in sets of three, known as codons, each of which corresponds to a specific amino acid.

While transfer RNA (tRNA) and ribosomal RNA (rRNA) are essential components of protein synthesis, they serve different roles. tRNA is responsible for bringing the appropriate amino acids to the ribosome, matching them to the codons on the mRNA, while rRNA forms the core structural and functional components of the ribosomes themselves.

Small interfering RNA (siRNA) is involved in the regulation of gene expression and is not directly involved in the process of protein synthesis. Thus, mRNA is indeed the type of RNA that is primarily responsible for the synthesis of proteins.