Transcription & Translation MCAT Practice Question
A clinician observes a patient with a mutation in the mitochondrial gene encoding 12S rRNA. This rRNA is a structural component of the 12S subunit, a key element of the mitochondrial ribosome (55S, composed of 12S and 16S rRNA). The mutation destabilizes the 12S rRNA structure. What is the expected consequence?
Answer choices
- ASelective loss of mitochondrial ribosome assembly and impaired mitochondrial protein synthesisCorrect answer
- BIncreased cytoplasmic protein synthesis by 80S ribosomes
- CEnhanced nuclear transcription of mitochondrial genes
- DActivation of the unfolded protein response in the endoplasmic reticulum
- EIncreased fidelity of amino acid incorporation by aminoacyl-tRNAs
- FAccumulation of mature 16S rRNA without proper ribosomal assembly due to uncoupling of the 55S ribosomal subunits
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