Glycocalyx-induced formation of membrane tubes

Area of Science:

• Biophysics
• Cell Biology
• Polymer Physics

Background:

• Tubular membrane structures are vital for cellular functions like trafficking and motility.
• The role of the glycocalyx in inducing membrane tube formation is not well understood.
• Existing models focus on external forces or protein curvature for tube formation.

Purpose of the Study:

• To investigate the mechanism by which the glycocalyx induces the formation of cylindrical membrane tubes.
• To develop a biophysical model combining polymer physics and membrane theory.

Main Methods:

• Developed a theoretical biophysical model.
• Integrated polymer physics theory with the Canham-Helfrich membrane theory.
• Analyzed the influence of glycocalyx properties on membrane shape.

Main Results:

• The glycocalyx alone can induce the formation of tubular membrane structures.
• Tube formation occurs via a first-order shape transition.
• Critical grafting density and polymer length are necessary for tube induction.
• Actin force, line tension, and spontaneous curvature reduce the critical parameters for tube formation.

Conclusions:

• The glycocalyx is a key factor in inducing membrane tube formation.
• The formation of membrane tubes by glycocalyx is energetically favorable, especially when combined with other cellular factors.
• This model provides insights into biological membrane morphogenesis.