PROTECTION FROM UV RAYSBy Tejas Kelkar

There are 3 major types of UV light, UVA, and UVB, and UVC

• UVA is detectable by cells and is just above the visible spectrum.

• UVB has a shorter wavelength, is can damage cells, and is really hard to detect.

• UVC is rarer, has a much shorter wavelength, and is germicidal. Which means it is really dangerous.

Name+ Abbreviation WavelengthUltraviolet A / UVA 400-315 nmUltraviolet B / UVB 315-280 nmUltraviolet C / UVC 280-100 nm

When there is no UV rays, people with lighter skin have at most a miniscule amount of melanin. Photosensors on cells in the lower epidermis sense UVA and tell melanosomes to produce melanin. They produce melanin, which surrounds the nucleus and protects it from radiation.

While the melanin accumulates, there is always a chance that DNA gets mutated

But there is one issue to this system: the photosensors cannot detect the more harmful UVB and UVC as well. Because of this, if there is a lot of UVB and UVC light present but not a lot of UVA, melanin may not build up, causing major health issues.

People with darker skin have a large amount of melanin production anyway. Because of that, even if there is UVB and UVC radiation, the cell won't be as affected. If it sees UVA, it will release melanin like normal. This is a much better defense against ultraviolet radiation.

As UVB and UVC hit the cell’s photosensors, they don’t respond, but when it tries to pass through the nucleus, the melanin prevents it.

When UVA radiation hits the cell’s photosensors, it acts like a normal cell, only more prepared.

Device that increases melanosome amounts

in cells

Device that increases melanosome activity

Therefore, these two devices

3.5 million people are DOCUMENTED each year getting skin cancer. That means they are most likely other cases in places where there isn’t knowledge of skin cancer

Random Fact

The Gene that controls it is called the Ocular Albinism type 1 gene (OA1), and it controls the production in two places. It controls the number of melanosomes produced and the melanosomes’ activity.

The gene should be altered to produce twice the amount of melanosome before stopping, and telling the melanosomes to produce more.

The Gene

OA1 Gene

Protein-Rab7 and Rab27a

Protien-Cystinosin

Controls melanosome activityControls

melanosome

production

Increasing this protein increases melanosome activity

Decreasing this protein increases melanosome production

So how could you reduce that number?

But the melanin still lets in 0.5% of the UV radiation, at least

This means 17,500 people will still get skin cancer each year

The spores of certain types of Bacillus bacteria (such as anthrax) can survive up to UVC radiation. If bacillus bacteria on your skin are given DNA instructions to form dormant spores that don’t respond to growing conditions, you could give yourself a transparent ultraviolet protector. The disadvantage of this is that if the spores are kept dormant, there wont be more bacteria, and spore production will stop.

Device for bacillus skin bacteria to form

dormant spores

No one really understands how the genes for this work, other than that fact that it works. The idea behind it is it surrounds the DNA with stuff to absorb the radiation, similar to melanin.

The aim is to make the bacteria stay this way.

The Gene

It would look something like this

Key

Altered Bacillus

Dormant Spore

Melanosome

Cell

DNA+Nucleus with the melanin coat

The bacterial spores block most of the UV rays, and the melanin in cells deals with UV that passes by the spores

Diagram of the devices working together

The issue with this is that if the bacterial spores don’t grow, the bacteria producing the spores will die out, and then the spore production stops. So instead, they should be instructed just to find the cold months good for growing.

How to keep the spores growing

When the sunlight hits the bacteria directly, with a lot of UV radiation (such as summer), the bacteria spores will stop growing. When the sunlight does not hit the bacteria directly, with a lot less UV radiation (winter), the spores will grow into bacteria.

Melanin absorbs harmful UV-radiation and transforms the energy into harmless amounts of heat through a process called "ultrafast internal conversion". Because of this, the bacterial spores could be told to track the amount of heat released instead.

How to keep the spores growing-the second way

When the bacteria senses a lot of heat, it will assume more radiation is there and not grow. When the bacteria does not sense a lot of heat, it will assume that there is less radiation grow. The one issue to this is not all heat is caused by the UV radiation.

One solution to this is have heat sensing proteins in the area where the melanin is. This could be used to tell the cell to produce a certain chemical that the bacteria think is part of their “perfect growing environment”

One protein that can sense heat well is AMPK. Cells could be told to produce this protein which would respond to heat given off by melanin interacting with UV. This could tell the cells to give off a signal to the bacteria to not grow.

Since the bacteria spores need to grow sometime, the winter is best for them, with 30-60% less UV radiation. But then you are defenseless against the other 40% (unless you naturally have dark skin). This is why you need both. One as your summer defense, one as your winter defense.

This method of ultraviolet protection would be costly. There isn’t a way to produce the right kind of bacillus that is safe for us (most of the workable bacteria are anthrax related), and putting the bacteria into producing dormant spores then they have good conditions to grow would be really difficult.

Possible Issues

• To produce the right kind of bacillus that is safe for us, we would need to change its genes to make it dependent on us, and get rid of any genes that could possibly hurt us. Either that or we could transfer the genes that make anthrax spores UV resistant into a safer bacteria

• To have the bacteria producing dormant spores, we would have to instruct the bacteria so that they think that the normal environment is not normal. This would cause them to stay as spores.

• To keep bacteria creation going, it could be made so the spores find the environment perfect in the fall (spring in the southern hemisphere) and grow, but in the other season they find the environment bad, and stop growing.

Solutions for Possible Issues