Phylogenetic Utility of rRNA ITS2 Sequence-Structure under Functional Constraint.

Area of Science:

• Molecular Biology
• Evolutionary Biology
• Bioinformatics

Background:

• The internal transcribed spacer 2 (ITS2) is vital for ribosome biogenesis, with its function dependent on conserved secondary and tertiary structures.
• Despite rapid evolution, ITS2 maintains specific structures under evolutionary constraints, linking function, structure, and evolution.
• Sequence-structure phylogeny of ITS2 is an emerging field for understanding these relationships.

Purpose of the Study:

• To review current knowledge on ITS2 processing in ribosome biogenesis, emphasizing conserved secondary structures.
• To explore the phylogenetic implications and applications of ITS2 structure information.
• To advocate for integrating structural data into phylogenetic analyses for improved accuracy.

Main Methods:

• Review of existing literature on ITS2 structure and function in ribosome biogenesis.
• Analysis of conserved structural characteristics, including motifs and cleavage sites.
• Discussion of structure-guided sequence alignment and phylogenetic tree construction.

Main Results:

• ITS2 exhibits conservative secondary structure features essential for its function.
• Structure information can guide sequence alignment, model base-pair mutations, and aid species identification.
• Incorporating structural data enhances the reliability and accuracy of phylogenetic trees.

Conclusions:

• Integrating ITS2 function, structure, and evolution expands traditional sequence-based phylogenetics.
• This approach contributes to a more comprehensive "tree of life" reconstruction.
• The conserved nature of ITS2 may inspire phylogenetic applications for other structured RNA regions.