Protein Synthesis

Front 1

Step 1

Back 1

A gene is activated as Transcription Factors bind to the Promoter that includes the TATA box of gene.

Front 2

Step 2

Back 2

RNA Polymerase 2 binds to the Promoter region of the gene forming the Transcription Initiation Complex.

Front 3

Step 3

Back 3

RNA Polymerase makes an mRNA copy of the gene in 5' to 3' direction from start point in Promoter to just past the polyadenylation signel.

Front 4

Step 4

Back 4

The 5' end of pre-mRNA is capped with a modified guanine.

Front 5

Step 5

Back 5

The 3' end of pre-mRNA is tagged with a poly-adenine tail.

Front 6

Step 6

Back 6

The pre-mRNA is edited by spliceosomes containing snRNPs and proteins that remove introns and splice together exons.

Front 7

Step 7

Back 7

mRNA passes through nuclear pore into the cytoplasm.

Front 8

Step 8

Back 8

A small ribosomal subunit with initiator tRNA bound attaches to the 5' end of mRNA.

Front 9

Step 9

Back 9

A large ribosomal subunit binds to the small ribosomal subunit forming the Translation Initiation Complex. Construction of this complex requires Initiation Factor proteins and GTP.

Front 10

Step 10

Back 10

Beginning at the start codon, the mRNA and tRNA move along the ribosome as a unit in the 5' to 3' direction using energy from GTP hydrolysis.

Front 11

Step 11

Back 11

Using ATP, amino acids are bound to specific molecules of tRNA by aminoacyl-tRNA synthetase.

Front 12

Step 12

Back 12

Using GTP tRNA with the bound amino acid is attached to mRNA, anticodon of tRNA to codon of mRNA. Each tRNA has an anticodon complementary to the mRNA codon that codes for a particular amino acid.

Front 13

Step 13

Back 13

Amino acids are moved into proper sequence and peptide bonds are formed between them by peptidyl transferase (ribozyme) with help of elongation factor proteins.

Front 14

Step 14

Back 14

When the Stop Codon reaches the A site, the completed polypeptide chain is released with the help of a protein called Release Factor and energy of GTP.