How Transcription and Translation Work (Animated)

DNA, or deoxyribonucleic acid, is the molecule that carries genetic instructions for all living things.The DNA molecule has a unique double helix structure, consisting of two strands that wind around each other.The backbone of each DNA strand is made of alternating sugar and phosphate molecules.Between these backbones are pairs of nucleotide bases. Adenine pairs with Thymine, and Guanine pairs with Cytosine.The sequence of these base pairs contains the genetic instructions, like a code that tells our cells what to do.RNA polymerase is an enzyme that reads this genetic code by approaching specific genes along the DNA molecule.When RNA polymerase begins transcription, it causes the DNA to unzip at specific points, separating the base pairs.This separation of DNA strands allows the transcription process to begin.RNA polymerase begins moving along the DNA template strand to start transcription.A 5-prime cap is added to protect the RNA and aid in its processing.A poly-A tail is added to the three-prime end, which will help protect the RNA and aid in its export from the nucleus.The completed messenger RNA separates from the DNA template strand.The messenger RNA is now ready for processing in the nucleus.Inside the nucleus, newly transcribed pre-messenger RNA contains both exons and introns.The spliceosome complex removes introns and joins the exons together.The mature messenger RNA, now containing only exons, moves through nuclear pores into the cytoplasm.In the cytoplasm, messenger RNA can interact with either free-floating ribosomes or those attached to the rough endoplasmic reticulum.Different types of proteins are made in different locations - membrane proteins are typically made on the rough ER, while cytoplasmic proteins are made by free ribosomes.The ribosome consists of two subunits that assemble around the messenger RNA.The ribosome recognizes the start codon AUG, which signals where protein synthesis should begin.The first transfer RNA carries methionine, which is always the first amino acid in a new protein.GTP molecules provide the energy needed for each step of translation.As translation continues, new transfer RNAs bring their amino acids to the growing protein chain.A peptide bond forms between the amino acids, linking them together in the growing protein chain.The ribosome then moves along the messenger RNA, positioning the next codon for translation.This process continues as each new transfer RNA brings its amino acid to the growing protein chain.Each step requires energy in the form of GTP, ensuring accurate and efficient protein synthesis.This elongation process continues until the ribosome reaches a stop codon, signaling the end of the protein coding sequence.As the ribosome reaches the stop codon, the completed polypeptide chain is released.The stop codon signals the end of translation, and release factors help free the new protein.The polypeptide chain begins to fold into its secondary structure, forming alpha helices and beta sheets.These secondary structures then fold into a complex tertiary structure, which gives the protein its unique functional shape.The final protein structure determines its function. Here we can see an enzyme catalyzing a chemical reaction by breaking down a substrate into products.And that completes our journey from DNA to functional protein, showing how the genetic code ultimately leads to the diverse molecular machines that keep our cells running.Thanks for learning about protein synthesis and folding with Spark.E!