In the lac operon,if a nonsense mutation occu | vedclass

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(A) The $lac$ operon consists of three structural genes: $lac\, z$,$lac\, y$,and $lac\, a$.$lac\, z$ codes for $\beta$-galactosidase,$lac\, y$ codes f

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$\beta$-galactosidase

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(A) The $lac$ operon consists of three structural genes: $lac\, z$,$lac\, y$,and $lac\, a$.$lac\, z$ codes for $\beta$-galactosidase,$lac\, y$ codes for permease,and $lac\, a$ codes for transacetylase.$A$ nonsense mutation in a gene introduces a premature stop codon,leading to the termination of translation for that specific polypeptide.Since $lac$ operon genes are transcribed as a single polycistronic mRNA,a mutation in $lac\, y$ will prevent the synthesis of functional permease.However,the translation of the upstream gene $lac\, z$ is unaffected,so $\beta$-galactosidase will still be synthesized.The downstream gene $lac\, a$ translation is typically affected by the nonsense mutation in the upstream $lac\, y$ gene due to the nature of polycistronic translation.Therefore,only $\beta$-galactosidase will be synthesized.

In the $lac$ operon,if a nonsense mutation occurs in the $lac\, y$ gene,which enzymes will be synthesized?

Similar Questions

Assertion $(A):$ Regulation of $lac$ operon by repressor is referred to as negative regulation.
Reason $(R):$ Repressor protein binds to the operator region and prevents $\text{RNA}$ polymerase from transcribing the operon.

Which one of the following enzymes is required for the entry of lactose into the $E. coli$ cell?

Which gene produces the lactose repressor?

Which enzyme$(s)$ is/are responsible for the transformation of lactose to galactose and glucose in the $E. coli$ culture medium?

In prokaryotic $DNA$,the recognition of the promoter region by $RNA$ polymerase is determined in some cases by the interaction of certain proteins with which sequences?

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