Question

3'- CCA TGT CCG GAA GTG AAT- 5' Using the same template DNA strand provided in question #1, transcribe and translate the DNA strand after the following mutations have occurred. You only need to provide the new amino acid sequence of the protein encoded after these mutations have occurred: a. A "C" to "T" base substitution at nucleotide position #8. b. A "T" to "C" base substitution at nucleotide position #6. c. Which one of these is more likely to have a negative impact on the cell? Explain your answer.

Answer 1

Transcribed mRNA sequence is 5' - GGU ACA GGC CUU CAC UUA -3' and protein formed is. Gly Thr Gly Leu His Leu.

Case A when when bases at 8 changes from C to T.then mRNA sequence be this. 5'- GGU ACA GAC CUU CAC UUA -3' then protein sequence is Gly Thr Asp Leu His Leu.

Case B. When changes from T to C at position no 6. Then resulted mRNA is 5'- GGU ACG GGC CUU CAC UUA -3'. Then protein sequence is Glu Thr Gly Leu His Leu. So in case A substitution mutation has negative effect as the incorporation of Asp(negative charge) occurs against Gly ( non polar). So the protein is abrupt in this case while in case B there is no change as such.