An increase in iron inside cultured hepatocytes leads to increased ferritin protein detected by Western blot but not by Northern blot or PCR. This indicates iron increases the frequency of which cellular process?

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Multiple Choice

An increase in iron inside cultured hepatocytes leads to increased ferritin protein detected by Western blot but not by Northern blot or PCR. This indicates iron increases the frequency of which cellular process?

Explanation:
Iron-regulated translation of ferritin is controlled by iron-responsive elements in ferritin mRNA. When iron rises, iron regulatory proteins release the iron-responsive elements, allowing ribosomes to translate ferritin mRNA more efficiently. This increases ferritin protein levels without changing the amount of ferritin mRNA, which is why a Western blot shows more ferritin protein while Northern blot or PCR show no change in mRNA. In short, the rise in ferritin protein reflects enhanced translation, a post-transcriptional control mechanism responsive to cellular iron.

Iron-regulated translation of ferritin is controlled by iron-responsive elements in ferritin mRNA. When iron rises, iron regulatory proteins release the iron-responsive elements, allowing ribosomes to translate ferritin mRNA more efficiently. This increases ferritin protein levels without changing the amount of ferritin mRNA, which is why a Western blot shows more ferritin protein while Northern blot or PCR show no change in mRNA. In short, the rise in ferritin protein reflects enhanced translation, a post-transcriptional control mechanism responsive to cellular iron.

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