Human long noncoding RNAs are substantially less folded than messenger RNAs.

Area of Science:

• Molecular Biology
• Genomics
• RNA Biology

Background:

• Long noncoding RNAs (lncRNAs) function as RNAs without coding proteins.
• Messenger RNAs (mRNAs) are crucial for translation and are often assumed to have limited secondary structure.
• RNA function is dictated by sequence or secondary structure, implying lncRNAs should be strongly folded.

Discussion:

• Genome-wide analysis of human RNA folding data revealed lncRNAs are less folded than mRNAs.
• This difference persists even when controlling for expression levels and GC content.
• Both lncRNAs and mRNAs exhibit stronger folding than random chance.

Key Insights:

• lncRNAs lack the positive correlation between folding strength and expression level seen in mRNAs.
• lncRNAs do not show the negative correlation between folding strength and evolutionary rate observed in mRNAs.
• These findings challenge the direct link between folding strength and expression/evolutionary rate for lncRNAs.

Outlook:

• RNA folding plays a significant role in RNA biology.
• The study suggests RNA folding is also critical for translation and/or protein biology.
• Further research is needed to elucidate the precise roles of RNA folding in different RNA types and cellular processes.