Wnt proteins are a family of secretory proteins that are typically charged at physiological pH. What type of charge do they have?

Wnt proteins are indeed typically positively charged at physiological pH, which refers to the normal pH of around 7.4 in the human body. This charge is primarily due to the presence of basic amino acids, such as lysine and arginine, in their structure. These amino acids can accept protons (H⁺) and end up with a positive charge under the conditions found in the body.

This positive charge is significant because it can affect how Wnt proteins interact with other molecules. The charged nature allows for electrostatic interactions with negatively charged components, such as certain cell surface proteins or glycosaminoglycans, facilitating binding and signaling processes critical in various biological pathways, particularly during embryogenesis and tissue homeostasis.

Understanding the charge of Wnt proteins is crucial not only for their function but also for their role in diseases like cancer, where Wnt signaling can become dysregulated.