Fold Commons

Body workers FoldLens Junior

Pick a part of your body. Meet the proteins doing the work there, then open one in 3D. Nothing here needs a login, and nothing about you is collected.

Blood (3)
  • Hemoglobin (alpha) Part of hemoglobin, which holds oxygen inside your red blood cells.
  • Hemoglobin (beta) The other part of hemoglobin. One changed letter in its gene causes sickle cell disease.
  • Serum albumin The most common protein in the liquid part of your blood. Fats and many medicines stick to it and travel with the blood.
Muscles (4)
  • Myoglobin Holds oxygen inside muscle cells.
  • Actin Links into long thin threads inside muscle cells.
  • Myosin Each myosin head changes shape when it uses ATP for energy. Many heads together slide the actin threads along, and the muscle shortens.
  • GLUT4 (glucose transporter) A doorway for sugar in muscle and fat cells. Insulin brings more of these doorways to the cell surface.
Eyes (2)
  • Rhodopsin Sits in the back of your eye. Light changes its shape, and that starts the signal for seeing.
  • Alpha-crystallin A Packed into the lens of your eye, it helps keep the lens clear.
Mouth and gut (4)
  • Alpha-amylase In your spit. It cuts starch into sugars.
  • Pepsin Works in the acid of your stomach, cutting food proteins into pieces.
  • Trypsin Cuts food proteins into smaller pieces in your small intestine.
  • Lactase Splits the sugar in milk. Many people make less of it as they grow up.
Skin and hair (3)
  • Keratin Builds hair, nails and the outer layer of your skin.
  • Collagen Long, strong ropes that hold your skin, tendons and bones together.
  • Tyrosinase Helps make melanin, the brown pigment in your skin, hair and eyes.
Brain and nerves (3)
  • Dopamine D2 receptor Sits on brain cells. When the signal chemical dopamine binds to it, the cell's signals change.
  • Acetylcholinesterase Breaks down the signal chemical acetylcholine where nerves meet muscles, so each signal ends quickly.
  • Sodium-potassium pump Uses energy to move sodium out of a cell and potassium in. Nerve signals depend on it.
Germ defence (3)
  • Antibody (IgG) Y-shaped proteins in your blood that stick to germs. Other parts of your defences then clear the germs away.
  • Lysozyme In tears and spit. It breaks open the walls of some bacteria.
  • Lactoferrin In milk and tears. It holds on to iron, which many germs need to grow.
Sugar control (1)
  • Insulin A signal made in the pancreas after you eat. When it binds, many of your cells take in more sugar from the blood.

These pictures come from AlphaFold, a computer prediction of each protein's shape, not a photo. More body workers: the field guide.