Pigment Cell of Ommatidia Pteridine Pathway orown Xanthopterin green-blue) lsoxa
ID: 197381 • Letter: P
Question
Pigment Cell of Ommatidia Pteridine Pathway orown Xanthopterin green-blue) lsoxanthopterin (violet-blue) Xanthine dehydrogenase 2-amino-4- GTP hydroxypteridine Biopterin GTP (blue) epi (blue) PD Drosopterin (red-orange) rimido- white biopterin diazepine Sepiapterin Isosepiapterin ellow Tryptophan oxygenase Kynurenine hydrolase Tryptophan Tryptophan-Kynurenine- (brown) Ommochrome Pathway 6. Based on the pathway diagram above, it appears that one mutant affects transport of precursors in both the pteridine and ommochrome pigment pathways. Whereas there is a mutant that affects transport of the precursor in just the pteridine pathway. If you were told that these mutant strains are each the result of different single-gene mutations, how could you explain this?Explanation / Answer
Answer:
Both the pathways are dependent on the membrane transporter.
So, a mutation in the membrane transport would affect both these pathways.
Each pathway is mediated by a specifc set of enzymes.
For example, mutations in Xanthene dehydrogenase affect only Pteridine pathway.
Mutations in tryptophan oxygenase affect only Ommochrome pathway.