Question

When players take steroid hormones, the hormones travel to muscle cells and act as transcription factors, activating transcription of genes that make muscle proteins. If each molecule of hormone triggers the transcription of 1500 mRNAs for the muscle protein myosin, and each mRNA transcript can be used as the template for translation 8 times before it is degraded, how many new myosin molecules get built for each molecule of injected steroid?

Answer 1

The number of new myosin per molecule of the injected steroid can be calculated as follows:

A single molecule of the hormone trigger the transcription of 1500 mRNA molecules. Translation of each mRNA transcript will be used as a template for the translation 8 times. This means that every translation will give the new molecule of the muscle protein myosin.

The number of mRNA triggered by the single hormone molecule = 1500

The number of translations done by the single transcript = 8

The number of translations done by the 1500 mRNA transcripts = 1500 × 8

=12,000

So, the number of new myosin per molecule of the injected steroid hormone will be 12,000.