An integrated, structure- and energy-based view of the genetic code.

Area of Science:

• Molecular Biology
• Genetics
• Biochemistry

Background:

• mRNA decoding is fundamental and conserved across life.
• Understanding interactions between mRNA, tRNA, and rRNA is crucial for deciphering genetic information transfer.

Purpose of the Study:

• To present an integrative view of mRNA, tRNA, and rRNA interaction networks.
• To derive an alternative, information-rich representation of the genetic code.
• To correlate tRNA modifications with genetic code structure and evolution.

Main Methods:

• Analysis of intrinsic stability of codon-anticodon duplexes.
• Examination of anticodon hairpin conformation and modified nucleotides.
• Investigation of non-Watson-Crick pairs and rRNA interactions at the A-site.

Main Results:

• A circular, unsymmetrical genetic code representation segregates GC-rich and AU-rich codon boxes.
• tRNA sequence variations and nucleotide modifications correlate with codon box types.
• Modified nucleotides at positions 34 and 37 stabilize AU-rich pairs and prevent miscoding.

Conclusions:

• The genetic code evolved from GC-rich origins with progressive A/U incorporation and tRNA modifications.
• The new representation aids in understanding tRNA roles and facilitates genetic code engineering for non-natural amino acids.