Essentials of Glycobiology—Part 4 (Turning Genes On or Off)

Larry A. Law

Every molecule, cell, or organism that interacts with a cell must do so in context of the glycocalyx. The glycocalyx is the surface membrane surrounding the cell. All interactions with the cell occur via cell-surface, sugar structures called cell receptors (glycoproteins or glycolipids) on the glycocalyx. Even more amazing, nearly every biological process supporting the life of the cell involves these sugars. Enzymatic reactions, transcripting DNA into mRNA, initiation and continuation of metabolic processes all entail sugars communicating and identifying needed actions within the cell cytoplasm.
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Communication from outside the cell to inside the cell is like a man typing on his laptop or cell phone. The keyboard represents the sugars and is the interface between the outside world (what the man wants to do) and the inside world of the computer (responding appropriately to handle the request from the outside world and take care of business on the inside to get things done).

Turning Genes On of Off

​The cell responds to its environment through these sugars. Genes get turned on or off as a result of the binding of molecules to cell-surface, sugar antennas on the outside of the cell. For example, the hormone insulin is secreted by the islet cells lining the pancreas when food is eaten, causing blood sugar to rise. High levels of glucose in the blood can become corrosive and the insulin is sent via the bloodstream to dock on insulin cell receptors on the cells. Those cell receptors are specifically wired so that when they are activated by the binding of the hormone insulin, they change shape (called a conformational change). This bending is like a person with a long-sleeved shirt. The bending causes part of the arm to be exposed. Inside the cell, proteins are uncovered (unsheathed). Now, these exposed proteins can be read and action taken inside the cell. Messenger molecules transit from the glycocalyx through the membrane of the nucleus, read a certain segment of the DNA, transcribe it into RNA, and follow the directions to open the flood gates and allow glucose to enter the cell from the surrounding fluid. The glucose can be used for energy in the mitochondria or be stored as glycogen for later use. It can even trigger storage as fat (yes—too much of the sugar glucose will make you fat)! This is why it is so important to govern what we eat.

In the same way as the hormone insulin connects to its corresponding cell receptor, nutrients, toxins, bacteria, and viruses can all dock on equivalent cell receptors and activate various metabolic processes. It becomes critical to fuel your body with what it needs to operate optimally. We don't put kool aid in formula one racing cars. However, some of us treat our bodies the same way and assume it doesn't matter what we eat. Eating food that is ultra-processed, altered, genetically modified, pesticide saturated, and dead does not fuel a living body. Only real, whole food, based primarily on living plant-sourced ingredients, augmented occasionally with meat that is humanely raised, will lead to health. In short, good food supports good genes and bad food suppresses good genes. It's always our choice, but the consequences are expressed in the quality of our body's operational performance and strength of our defensive immune system.

The figure below shows insulin docking on a cell receptor and initiating actions to take place inside the cell, resulting in the gate being opened to allow glucose into the cell. Without step one occurring, steps 2-5 do not happen and a disease called insulin resistance or type 2 diabetes begins to manifest within our body.