Genes & Proteins

Genes vs. Proteins

Your DNA is like an instruction manual that comes in two major types. One type contains the instructions or "codes" for a sequence of amino acids. This sequence makes proteins. Segments of DNA that encode proteins are called genes. 

Proteins are large molecules that play important roles in your body. Even though your cells can build proteins from genes, you can also find them in certain foods. 

For example, meat and tofu contain lots of protein. When you eat these foods, your body breaks them down into amino acids and uses these amino acids to make its own proteins. 

Proteins function as:

• Antibodies: Made by the immune system to neutralize foreign substances, like viruses.
• Enzymes: Enable chemical reactions to occur in the body.
• Messengers: Send signals in the body. For example, serotonin is a nervous system messenger. Hormones like insulin are also messengers. 
• Structural proteins: Support cell structures. Collagen is the most abundant structural protein in the body.
• Transport proteins: Carry substances throughout the body. An example of a transport protein is the sodium-potassium pump. This protein is essential for brain cell function.

Note that there’s another type of DNA that’s "non-coding." While it doesn't code for proteins, non-coding DNA helps determine how much protein to make and when to make it. In fact, a lot of the differences between people come from non-coding DNA.

How Are Proteins Made?

When your cells need to use DNA to make proteins, parts of chromosomes unravel. Unraveled chromosomes allow biological machines to enter and “read” that part of the DNA. These machines then copy a molecule from the DNA into a “messenger molecule” called RNA. Scientists call this process transcription.

The RNA then travels outside the nucleus, where other biological machines read it as a “recipe” for making proteins. We call this process translation.