Disordered proteins interact with the chemical environment to tune their protective function during drying

Area of Science:

• Biochemistry
• Molecular Biology
• Structural Biology

Background:

• Intrinsically disordered proteins (IDPs) and cosolutes are crucial for desiccation tolerance.
• IDP function is sensitive to the intracellular environment, especially during extreme drying.
• The mechanistic interplay between IDPs and cosolutes in desiccation protection remains poorly understood.

Purpose of the Study:

• To investigate how endogenous cosolutes enhance the protective function of desiccation-related IDPs.
• To determine if IDP structural parameters correlate with cosolute synergy.
• To elucidate the mechanisms underlying IDP-cosolute synergy in different protein families.

Main Methods:

• Studied desiccation-related IDPs from four organisms across LEA and CAHS protein families.
• Assessed IDP-cosolute synergy during drying.
• Analyzed structural parameters of protective IDPs.
• Investigated CAHS and LEA protein self-assembly and gel formation.

Main Results:

• Desiccation-related IDPs synergize with endogenous cosolutes to enhance protection.
• No correlation found between structural parameters and synergy for LEA or CAHS proteins.
• CAHS protein synergy is linked to self-assembly and gel formation, unlike LEA proteins.

Conclusions:

• Functional synergy between IDPs and cosolutes is a convergent desiccation protection strategy.
• Mechanisms of IDP-cosolute synergy vary between protein families (e.g., CAHS vs. LEA).
• Understanding these interactions is key to improving desiccation tolerance in biological systems.