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Codon number 156 157 158 159 160 161 162 163 Normal Person: ATG CAG GAA CTC AAT

ID: 176371 • Letter: C

Question

Codon number

156

157

158

159

160   

161

162

163

Normal Person:

ATG

CAG

GAA

CTC

AAT

Codes for Asn

TCT

CGG

CTG

Your patient

ATG

CAG

GAA

CTC

TAT

Codes for Tyr

TCT

CGG

CTG

Keratins forms major components of skin, hair, horn and feathers and this protein is robust and relatively insoluble and their quaternary structure play important roles in the maintenance of physical structure of animals. In addition to this the secondary structures (the -helix and -sheet) plays important role in the architecture of keratins. If Asn at 160th position is replace with tyrosine then the tyrosine being a hydrophilic residue will try to destabilize the transmembrane state and as tyrosine with hydrophilic domains cannot cross the membrane and thus results in the blocking of any transmembrane and non-transmembrane equilibration state and the consequence change brought by these charged ionized residues will destabilize the transmembrane state of keratin structure.

K10 , suprabasal (EH:160 (Tyr-----> Asp) This substitution will bring a change in the suprabasal specific keratin polypeptide expression thus filament stability will be disturbed. This altered expression along with structural composition change has resulted in the thickening of the skin on his palms and soles.

Please explain when the Asn is in the keratin structure and how changing it to Tyr affects the protein?

156

157

158

159

160   

161

162

163

Normal Person:

ATG

CAG

GAA

CTC

AAT

Codes for Asn

TCT

CGG

CTG

Your patient

ATG

CAG

GAA

CTC

TAT

Codes for Tyr

TCT

CGG

CTG

Explanation / Answer

Keratin forms a major component of skin, hair, horn and feathers and this protein is robust and relatively insoluble and their quaternary structure play important roles in the maintenance of physical structure of animals. In addition to this the secondary structures (the -helix and -sheet) plays important role in the architecture of keratins.

If Asn at 160th position is replace with tyrosine then the tyrosine being a hydrophilic residue will try to destabilize the transmembrane state and as tyrosine with hydrophilic domains cannot cross the membrane and thus results in the blocking of any transmembrane and non-transmembrane equilibration state and the consequence change brought by these charged ionized residues will destabilize the transmembrane state of keratin structure.

K10 , suprabasal (EH:160 (Tyr-----> Asp) This substitution will bring a change in the suprabasal specific keratin polypeptide expression thus filament stability will be disturbed. This altered expression along with structural composition change has resulted in the thickening of the skin on his palms and soles.