How Tattoos Really Work... At Least in Mice

TL;DR

Immune cells called melanophages absorb tattoo ink, leading to the staying power of tattoos, while genetic engineering shows promise in creating drought-resistant plants.

Transcript

SciShow is supported by Skillshare. ♪ Tattooing goes way back in human history. We’ve been inking ourselves for thousands of years. And yet, exactly how the ink sticks around has remained somewhat of a mystery. The rough idea was that either some skin cells or immune cells absorb ink particles, and then basically never die. Unless it’s been a long ... Read More

Key Insights

• 😉 Melanophages, a type of immune cell, are responsible for absorbing tattoo ink and contributing to the longevity of tattoos.
• 🚾 Genetic engineering shows promise in creating drought-resistant plants by manipulating a gene called PsbS, which conserves water by partially closing stomata.
• 😉 The findings from these studies contribute to our understanding of ink absorption and water conservation in plants, with potential applications in the fields of tattoo artistry and agriculture.
• 👨‍🔬 The research conducted on mice and tobacco plants provides a foundation for further experiments to develop more effective tattoo removal techniques and drought-tolerant crops.

Questions & Answers

Q: What role do melanophages play in the longevity of tattoos?

Melanophages, a type of immune cell, absorb tattoo ink and hold onto it. As these cells continuously die and are replaced, the ink remains in the skin, explaining why tattoos stay visible.

Q: How did researchers determine the role of melanophages in ink absorption?

Researchers used genetically modified mice that allowed them to kill off macrophages, the immune cells responsible for ingesting foreign substances. By observing and analyzing the cells present in tattooed skin, they found evidence of melanophages absorbing ink.

Q: What protein was found to contribute to water conservation in plants?

PsbS, a protein found in Photosystem II of plants, was discovered to increase water conservation when its amount was manipulated. Plants with higher levels of PsbS had partially closed stomata, reducing water loss through evaporation.

Q: What were the drawbacks observed in genetically modified drought-resistant plants?

Some of the engineered plants were less productive than normal plants, showing traits such as decreased height, mass, or fewer leaves. The reason for this variability is still unknown.

Summary & Key Takeaways

• A new study reveals that immune cells called melanophages are responsible for absorbing tattoo ink, debunking previous theories about ink absorption. These cells die and are replaced by new cells that continue to hold onto the ink.

• Researchers have discovered a single gene, PsbS, that can be manipulated to make plants more tolerant to drought. By increasing the amount of PsbS, plants conserve water by partially closing their stomata, reducing water loss while still obtaining enough carbon dioxide for photosynthesis.