Long non-coding RNA

Definition

Long non-coding RNAs (lncRNAs) are a class of RNA molecules that are longer than 200 nucleotides and do not code for proteins. Instead, they play critical roles in regulating gene expression and chromatin structure, impacting various biological processes such as development, differentiation, and response to environmental signals.

5 Must Know Facts For Your Next Test

1. LncRNAs can regulate gene expression by interacting with transcription factors, RNA polymerase II, and other components of the transcription machinery.
2. These molecules can influence chromatin modifications by recruiting epigenetic modifiers to specific genomic regions, thereby altering the accessibility of DNA for transcription.
3. LncRNAs are involved in various cellular processes, including X-chromosome inactivation, genomic imprinting, and the regulation of stem cell pluripotency.
4. Some lncRNAs can function as molecular scaffolds, bringing together multiple proteins or RNA molecules to form functional complexes that modulate gene activity.
5. Dysregulation of lncRNAs has been implicated in various diseases, including cancer, neurological disorders, and cardiovascular diseases, highlighting their importance in health and disease.

Review Questions

• How do long non-coding RNAs influence gene expression and what mechanisms are involved?
  • Long non-coding RNAs influence gene expression through several mechanisms. They can bind to transcription factors and other proteins involved in the transcription process, thereby modulating the activity of target genes. Additionally, lncRNAs can interact with chromatin remodeling complexes to alter the chromatin structure around specific genes, making them more or less accessible for transcription. This regulatory capacity allows lncRNAs to play significant roles in various biological processes.
• Discuss the role of long non-coding RNAs in epigenetic regulation and how they might affect cellular functions.
  • Long non-coding RNAs are key players in epigenetic regulation as they can recruit chromatin-modifying enzymes to specific genomic locations. By influencing histone modifications and DNA methylation patterns, lncRNAs can alter the chromatin landscape, leading to changes in gene accessibility and expression. This capacity for epigenetic modification impacts numerous cellular functions such as differentiation and response to environmental cues, demonstrating their critical role in maintaining cellular identity and function.
• Evaluate the implications of dysregulated long non-coding RNA expression in disease development and progression.
  • Dysregulated expression of long non-coding RNAs has significant implications for disease development and progression. In cancer, for example, certain lncRNAs may promote tumorigenesis by activating oncogenes or silencing tumor suppressor genes through epigenetic mechanisms. Additionally, altered lncRNA levels have been associated with neurological disorders and cardiovascular diseases, suggesting that they may serve as potential biomarkers or therapeutic targets. Understanding these connections highlights the importance of lncRNAs in health and disease contexts.

Related terms

Gene expression: The process by which the information in a gene is used to produce a functional product, typically a protein, which can be regulated at multiple levels.

Chromatin remodeling: The dynamic modification of the structure of chromatin that allows access to DNA for transcription and other processes, often influenced by non-coding RNAs.

Epigenetics: The study of heritable changes in gene expression that do not involve changes to the underlying DNA sequence, often regulated by molecules like lncRNAs.