SLC24A5, the molecular genetics?

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How Skin Color Is Determined:

In 2005 researchers identified a gene called SLC24A5 as a key determinant of skin color. Rebecca Ginger and colleagues now confirm that the protein product of this gene (NCKX5) is an ion exchanger; it exchanges sodium for calcium across a membrane, regulated by potassium. But unlike other NCKX proteins, they found that NCKX5 is not present on the cell surface, but internally in a compartment known as the trans-Golgi network. This compartment is where new proteins and vesicles are processed, modified and sorted.

When the researchers knocked out NCKX5 in melanocytes (the skin cells that manufacture the melanin pigment), melanin production decreased dramatically. They also demonstrated that changing the ancestral amino acid (alanine) at position 111 to the European form associated with lighter skintone (threonine) reduced NCKX5′s exchanger activity.

Related: SLC24A5 and skin color.

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One Comments

  1. Yes, skin pigmentation is highly dependent on vesicular transport. Many forms of albinism involve microtubule or vesicular anomalies. But I think that NCKX5 would have to have tissue specific expression, because modification of the trans-golgi network sounds bad in other secretory type cells.

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