Course/Module 3/Lesson 6

Lesson 6

How Eumelanin Is Built

The Molecular Cascade

⏱ 0:43
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Audio Narration

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"Now that you know what it does, let me show you the assembly line. It is a precise sequence of chemical events."
Key Terms
  • Tyrosine: The amino acid building block of melanin.
  • Tyrosinase: The enzyme that acts as the foreman of the melanin factory.
  • Dopaquinone: A critical fork-in-the-road molecule in melanin synthesis.
  • MITF: The master protein that tells cells to start making melanin tools.

Building eumelanin starts with an amino acid called tyrosine. An enzyme called tyrosinase (which needs copper to work) turns tyrosine into dopaquinone. This is the moment of truth. If MC1R is functional and the signal is strong, the cell follows the eumelanin path, creating building blocks called DHI and DHICA. These units then stack together in a process called polymerization, like Lego bricks forming a solid wall. This stacking creates a biological semiconductor — a material that can conduct both ions and electrons.

TYROSINEDOPAQUINONEDHI/DHICAPOLYMEREUMELANIN ASSEMBLY LINE

Key Takeaways

  • ◈ Melanin synthesis is a multi-step chemical cascade.
  • ◈ Tyrosinase is the essential enzyme for the whole process.
  • ◈ The final product is a biological semiconductor capable of conducting electricity.
Collapse Check — Reflection

Apply Your Intelligence

What happens if one of the 'foremen' (like tyrosinase) is missing from the factory?

Next: But what if the factory gets a different set of instructions? Let's talk about the Sulfur Trap.
Module Overview