Long non-coding RNA

Definition

Long non-coding RNAs (lncRNAs) are a class of RNA molecules that exceed 200 nucleotides in length and do not encode proteins. Instead, they play crucial regulatory roles in various biological processes, including transcriptional regulation, chromatin remodeling, and gene expression. These molecules are involved in the complex control of gene networks and can influence cellular functions by interacting with DNA, RNA, and proteins.

5 Must Know Facts For Your Next Test

1. Long non-coding RNAs are involved in various cellular processes, including differentiation, proliferation, and apoptosis, highlighting their importance in maintaining cellular homeostasis.
2. Many lncRNAs are found in the nucleus and can influence gene expression by modifying chromatin structure or recruiting transcription factors to specific genomic regions.
3. lncRNAs can also function as molecular scaffolds, bringing together different proteins and RNA molecules to facilitate complex regulatory processes.
4. Some lncRNAs are known to be involved in diseases, including cancer, where they can contribute to tumorigenesis by dysregulating normal gene expression patterns.
5. The expression levels of lncRNAs can vary significantly across different tissues and developmental stages, suggesting they play specialized roles in specific biological contexts.

Review Questions

• How do long non-coding RNAs influence transcriptional regulation within eukaryotic cells?
  • Long non-coding RNAs influence transcriptional regulation by interacting with various components of the transcriptional machinery, such as transcription factors and RNA polymerase. They can act as guides to direct these factors to specific genomic regions or alter chromatin states to either promote or inhibit gene expression. Through these mechanisms, lncRNAs play a crucial role in fine-tuning the regulation of genes involved in critical cellular processes.
• Evaluate the role of long non-coding RNAs in epigenetic regulation and how this impacts gene expression.
  • Long non-coding RNAs contribute to epigenetic regulation by recruiting chromatin-modifying complexes to specific genomic sites. This recruitment can lead to modifications such as histone methylation or acetylation, which ultimately influence the accessibility of DNA for transcription. By altering the chromatin landscape, lncRNAs can either silence or activate nearby genes, demonstrating their significant impact on gene expression through epigenetic mechanisms.
• Synthesize information about how long non-coding RNAs could be leveraged for therapeutic applications in disease management.
  • Long non-coding RNAs present exciting opportunities for therapeutic applications due to their involvement in disease mechanisms like cancer. Researchers are exploring methods to target specific lncRNAs using small molecules or RNA-based therapies to restore normal gene expression patterns. Additionally, lncRNAs could serve as biomarkers for disease diagnosis or prognosis, allowing for personalized treatment approaches. By understanding the functional roles of lncRNAs in disease pathways, novel strategies can be developed to modulate their activity and improve patient outcomes.

Related terms

Transcription Factor: Proteins that bind to specific DNA sequences to regulate the transcription of genes, often by enhancing or inhibiting the recruitment of RNA polymerase.

Epigenetics: The study of heritable changes in gene expression that do not involve alterations to the underlying DNA sequence, often mediated by chemical modifications such as methylation.

MicroRNA: Small non-coding RNA molecules, typically 20-22 nucleotides long, that regulate gene expression by binding to complementary sequences on target mRNAs.