TPR repeats and ELTR pattern: length variation as a function evolution mechanism

Area of Science:

• Protein structure and evolution
• Bioinformatics and computational biology
• Molecular and structural biology

Background:

• Tandem repeat proteins (TRPs) are ubiquitous in biology.
• The tetratricopeptide repeat (TPR) is a common protein motif, originally defined as a 34 amino acid structural repeat (TPR-34).
• Equal length tandem repeats (ELTR) have been proposed as the ancestral repeat pattern.

Purpose of the Study:

• To investigate the length polymorphism of TPR repeats.
• To identify novel TPR repeat variants and assess their functional implications.
• To explore the role of length variation in the evolution of TRP functions.

Main Methods:

• Analysis of TPR repeat sequences using the PATTINPROT tool.
• Identification and characterization of TPR repeat length variants.
• Correlation analysis between TPR repeat length and protein function.

Main Results:

• Discovery of two novel, longer TPR repeat variants: 40 and 42 amino acids.
• Identification of a strong correlation between increased TPR repeat length and new functional capacities in proteins.
• Evidence supporting length variation as a key driver for functional diversification in repeat-containing proteins.

Conclusions:

• TPR repeat length is not conserved and exhibits significant polymorphism.
• Longer TPR variants (40 and 42 amino acids) contribute novel functional capabilities.
• Length variation in TPR repeats is a crucial mechanism for the evolutionary adaptation and functional diversification of proteins.