(Themes 4+5) The spicy flavor of chili peppers derives in part from compounds called capsaicinoids. Levels of this compound in the pepper were recently found to be affected by mutations in the PAMT gene, which encodes a putative aminotransferase enzyme. Maps of the pAMT gene region in two peppers are shown below; numbered vertical lines represent exons. Devil's Yellow peppers have a Tcc transposon insertion in intron 3 of the pAMT gene, which leads to ~50% less capsaicinoid content as compared with Red Habanero peppers. Genome mRNA structure (a) Red Habanero || 12 3 |||||||||||| 45 67 89 10 11 12 13 14 15 16 (b) Devil's Yellow ||H 12 3 Tcc 17 67 1.0 kb ⇓⇓⇓||||||| 89 10 11 12 13 14 15 16 45 591 bp (Tanaka et al 2019 Plant Journal) 17 1 2 3 4 1 2 3 4 17 ….. 17 Scientists sequenced the mRNA expressed from the two peppers, and found the exon structure shown at right. The Devil's Yellow pepper now contained an extra region of sequence (grey box) containing partial Tcc transposon sequence that forms nonfunctional pAMT. a) Propose a hypothesis of what step in gene expression was affected by the Tcc insertion to produce the indicated mRNA structure, and briefly justify your answer, including specifying what sequences or properties must be contained within Tcc to produce this result. b) Given that all 17 expected exons are still present in the mRNA expressed by Devil's Yellow peppers, why might this Tcc- altered pAMT be nonfunctional? Briefly propose and justify one molecular hypothesis about what functional aspect of the mRNA could have been affected, and how this led to the loss of pAMT function.

When the expression of a single trait is influenced by two or more different non-allelic genes, it is termed as genetic interaction. According to Mendel's law of inheritance, each gene functions in its own way and does not depend on the function of anoth…

Gene expression is a process by which the instructions present in deoxyribonucleic acid (DNA) are converted into useful molecules such as proteins, and functional messenger ribonucleic (mRNA) molecules in the case of non-protein-coding genes.