Which sets of mrna codons could genetically code for a protein with the following amino acid composition: pro - asp - gly - lys

Ans.

During protein synthesis, genetic information gets transferred to mRNA from DNA as codons. Each codon or genetic code is made up of three nucleotide bases and codes for a specific amino acid during translation. The genetic code for proline is CCU, for aspartate is GAC, for glycine is GGU, and for lysine is AAA.

Thus, the mRNA codons that can code for a protein with given sequence is CCU-GAC-GGU-AAA.

However, the sequence may change these amino acids also can be coded by other codons because  there are more than one codon for many amino acids).

step 1: initiation

initiation is the beginning of transcription. it occurs when the enzyme rna polymerase binds to a region of a gene called the promoter. this signals the dna to unwind so the enzyme can ‘‘read’’ the bases in one of the dna strands. the enzyme is now ready to make a strand of mrna with a complementary sequence of bases.

step 2: elongation

elongation is the addition of nucleotides to the mrna strand. rna polymerase reads the unwound dna strand and builds the mrna molecule, using complementary base pairs. there is a brief time during this process when the newly formed rna is bound to the unwound dna. during this process, an adenine (a) in the dna binds to an uracil (u) in the rna.

step 3: termination

termination is the ending of transcription, and occurs when rna polymerase crosses a stop (termination) sequence in the gene. the mrna strand is complete, and it detaches from dna.