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The CFTR consists of single peptide chain with transmembrane segments and extracellular and intracellular regions. Which of the following peptide segments of CFTR is most likely located in a transmembrane segment?

A) Asp-Val-Leu-Thr-Glu-Lys-Glu-Ile
B) Glu-Glu-Thr-Glu-Glu-Glu-Val-Gln
C) Ile-Phe-Val-Leu-Ile-Trp-Cys-Leu
D) Lys-Ile-Lys-His-Ser-Arg-Gly-Arg
E) Ser-Thr-Gly-Ala-Gly-Lys-Thr-Ser
 

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Wait a minute
Somebody please explain for me the whole issue.
I did not understand the question neither it's answer :confused:
CFTR - Cystic fibrosis transmembrane conductance regulator. Mutation in CFTR leads to cystic fibrosis. In stem no word about CF.
Now only pure logic - we know that deletion of Phe in 508 leads to CF. From present choices, only C has Phe inside. So, assuming that no mutation present in transmembrane segment, what else we have to do, --> Phe is present --> choice C. May be they are non-polar on second look, but pure logic more fast :rolleyes:.
I don't know exact order in CFTR and don't want to know, because in this segment are amino acids from 433 to 586
 

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CFTR - Cystic fibrosis transmembrane conductance regulator. Mutation in CFTR leads to cystic fibrosis. In stem no word about CF.
Now only pure logic - we know that deletion of Phe in 508 leads to CF. From present choices, only C has Phe inside. So, assuming that no mutation present in transmembrane segment, what else we have to do, --> Phe is present --> choice C. May be they are non-polar on second look, but pure logic more fast :rolleyes:.
I don't know exact order in CFTR and don't want to know, because in this segment are amino acids from 433 to 586
indeed better use logic with this kind of question; when I saw all the AA; I was about to have a heart attack :))
 
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