Answer
A) Phenylalanine is a nonpolar aromatic amino acid while tyrosine is a polar amino acid. Therefore, changing tyrosine to Phenylalanine will disturb the polarity and strength of the protein. This could be oncogenic because this position is directly related to the tyrosine kinase activity of SRC kinase.
B) The original sequence of the SRC kinase from 249 to 253 is PTSKP. This region is important for the SH2-kinase linker. The changed sequence is APTMP. P to A; S to T changes are synonymous, T to P; K to M changes are non-synonymous. Therefore, this is an oncogenic change.
Work Step by Step
A) Phenylalanine is a nonpolar aromatic amino acid while tyrosine is a polar amino acid. Therefore, changing tyrosine to Phenylalanine will disturb the polarity and strength of the protein. This could be oncogenic because this position is directly related to the tyrosine kinase activity of SRC kinase.
B) The original sequence of the SRC kinase from 249 to 253 is PTSKP. This region is important for the SH2-kinase linker. The changed sequence is APTMP. P to A; S to T changes are synonymous, T to P; K to M changes are non-synonymous. Therefore, this is an oncogenic change.
