DNA & Protein Synthesis

2 –Making Proteins

Your challenge

• To recreate the process by which a cell produces a protein.

• Your desk is the cell.– Half of the group/desk represents the nucleus.– The nucleus contains the DNA sequence from

which you are going to make your protein.– The other half of the group/desk represents a

ribosome within the cytoplasm.

Stage 1 - Planning

• What does the ribosome need to make a protein?

• How is the sequence of bases transferred to the ribosome?

Stage 2 – Preparation & Transcription

• One member of the group collect:Amino acidsSellotapeWhite board

• One member of the “nucleus group” should nominate themselves to be mRNA. You should come to the nucleus, “unzip” the DNA and transcribe the sequence.

Stage 3 – Protein building (Translation)

• After transcription is complete, the DNA strands reconnect.

• Sort the bases on the mRNA molecule into codons.• The mRNA strand can now be translated.• There is a special codon called the start codon

(met) translation will start here. This is the codon that corresponds to Met amino acid.

• Use the protein decoder to work out which codon makes which amino acid.

• Put your amino acids together in the correct sequence to produce a polypeptide chain.

• Have your protein checked by the teacher.

When the mRNA strand reaches the ribosome the amino acids must be joined in the order coded for by the mRNA strand.

TASK: Describe the steps for building a protein & draw DNAmRNA Amino acids

DNA:TAC GGC AAT CGC ACG ATG CGC AGC GTA ATC

mRNA:AUG CCG UUA GCG UGC UAC GCG UCG CAU UAG

Amino acids:Start--Pro--Leu--Ala--Cys--Tyr--Ala—Ser—His--Stop