Intrinsically disordered segments affect protein half-life in the cell and during evolution

Area of Science:

• Molecular Biology
• Biochemistry
• Genetics

Background:

• Protein turnover is crucial for maintaining cellular balance (homeostasis).
• The ubiquitin-proteasome system degrades proteins, but how protein structure affects degradation rates is unclear.

Purpose of the Study:

• To investigate the relationship between intrinsically disordered protein segments and protein half-life.
• To explore the role of disordered segments in protein degradation and cellular function.

Main Methods:

• Comparative analysis of protein half-lives in yeast, mouse, and human cells.
• Examination of intrinsically disordered segments within proteins.
• Analysis of gene duplication events and their impact on protein structure and half-life.

Main Results:

• Proteins with intrinsically disordered segments (terminal or internal) exhibit significantly shorter half-lives.
• The length of disordered segments correlates with proteasome interaction.
• Gene duplication leading to altered disordered segments in yeast paralogs affects protein half-life, particularly in signaling proteins.

Conclusions:

• Intrinsically disordered segments are key determinants of protein half-life.
• Variation in disordered segment length and position contributes to genetic diversity and phenotypic variation.
• Altered protein half-lives due to disordered segments can impact cellular signaling and function.