TRANSLATION PRESENTATION

TRanslation

Presentation By: Jonathan Cuellar, James Knapp, David Garza, and Russell Long

START

What Is Translation?

Important Terms

TRNA

mRna

Ribosomes

Amino Acids

Initiation

What happens in Initiation?

ELONGATION

TERMINATION

The Role of Ribosomes

tRNA & Amino Acids

THANKS!

Tanslation

Translation is the process in biology where the cell uses the instructions in messenger RNA (mRNA) to build a protein.

There are 3 main steps in Translation1. Initiation: The ribosome gets the mRNA and finds the start of the recipe. 2. Elongation: tRNA brings amino acids, and the ribosome connects them in a chain. 3. Termination: When the ribosome reaches the end of the recipe, the protein is finished.

Amino Acids

Amino acids are the building blocks of proteins. Each codon on mRNA corresponds to one specific amino acid. There are 20 different amino acids, and their order determines the protein's shape and function. During translation: Amino acids are brought to the ribosome by tRNA. The ribosome links them together into a chain using strong bonds called peptide bonds.

tRNA

Transfer RNA (tRNA) brings the building blocks (amino acids) to the ribosome.- tRNA acts like a delivery truck bringing the right amino acid to the ribosome. Each tRNA has: An anticodon: This matches up with a specific codon on the mRNA, like a puzzle piece. An amino acid: The building block for proteins that it carries. For example: The codon AUG on mRNA pairs with the anticodon UAC on tRNA. This tRNA carries the amino acid methionine, which starts the protein.

Termination

Stop Codon Recognition: A stop codon (UAG, UAA, or UGA) is reached. These codons do not encode any amino acids, but rather it signals the end of the translation process. Release Factors: A stop codon enters the ribosome's A site, releasing factors such as proteins RF1, RF2 in prokatyotes or eRF in eukaryotes and bind to the ribosome. Dissociation: The ribosome subunits separate, and the mRNA and polypeptide are released. The ribosomal components are now free to be reused in a new cycle of translation.

Role of Ribosomes

Ribosomes are molecular machines responsible for synthesizing proteins by translating messenger RNA into a polypeptide chain. They are essential components of the cell's machinery and play a important role in gene expression.

Small Subunit: Binds to mRNA and reads the genetic code. Large Subunit: Facilitates the formation of peptide bonds between amino acids.

This is the "arrival" station. New transfer RNA (tRNA) molecules bring in amino acids here.

This is the "production" station. The amino acid carried by the tRNA in this spot gets attached to the growing protein chain.

This is the "exit" station. Once a tRNA has delivered its amino acid and is no longer needed, it moves here and leaves the ribosome.

tRNA or Transfer RNA

Plays a very important role in the protein synthesis process

Amino Acid Charging: tRNA molecules are charged with their connecting amino acids through aminoacyl-tRNA synthetases.Decoding mRNA: Think of tRNA as a fetching mechanism, matching the correct mRNA with the correct amino acid. Anitcodons on the tRNA pair with the complementary codon on the mRNA during translation. The tRNA then carries the amino acid to the ribosome. The formation of peptide bonds is facilitated through the ribosome. The amino acids are attached to the tRNA and the peptidyl site(P) and to the aminoacyl site(A) The tRNA then exits the ribosome through the E-site or Exit site and the process begins again.

mRNA

The mRNA is like a recipe with instructions for making a specific protein. - Think of mRNA as a copy of the instructions from DNA. - DNA lives safely inside the nucleus, but the cell needs its instructions out in the cytoplasm to make proteins. So, the DNA sends mRNA as a messenger carrying a sequence of "letters" (called codons). Each codon has three letters and tells the ribosome which building block (amino acid) to use.

Ribosomes

The ribosome is the protein-making machine that reads the recipe. The ribosome is like a factory machine where proteins are built. It reads the instructions on the mRNA, one codon at a time. The ribosome has two parts: A small subunit that holds the mRNA in place. A large subunit that assembles the protein by connecting amino acids. The ribosome also has three special sites where the building happens: A site: New tRNA arrives here with an amino acid. P site: The protein chain grows here. E site: Empty tRNA exits here.

Elongation

Codon Recognition: The ribosome, which consists of two subunits reads the mRNA in groups of three nucleotides called codons. With each codon corresponding to a specific amino acid. A tRNA with an anticodon, complementary to the codon of the mRNA binds to the ribosome. Peptide Bond Formation: The ribosome forms a peptide bond between the newly added amino acid brought by the tRNA and the growing polypeptide chain. Then the tRNA in the P (peptidyl) site transfers the polypeptide to the tRNA in the A (aminoacyl) site. Translocation: The ribosome moves along the mRNA, shifting the tRNA from the A site to the P site. Then the empty tRNA moves to the E (exit) site and is released.

Initiation

What Happens?

The small ribosomal subunit binds to the mRNA and locates the start codon (AUG). The initiator tRNA, carrying methionine, pairs with the start codon. The large ribosomal subunit joins, forming the translation initiation complex. The ribosome is now ready to begin elongation.

Amino Acids

Amino acids are the monomers that make up proteins. During translation, they are aligned into a polypeptide chain in a specific sequence according to the mRNA.

Aminoacyl-tRNA Synthetase(enzyme)

The process by which amino acids are activated and attached to tRNA. Once attached to tRNA, amino acids are moved into the ribosomal area.

• Peptide Bond is formed through one amino acid reacting with a carboxyl group of the previous amino acid
• Elongation occurs with the enzyme called peptidyl transferase