Long non-coding RNA (lncRNA)

Definition

Long non-coding RNA (lncRNA) refers to a diverse group of RNA molecules that are longer than 200 nucleotides and do not encode proteins. These RNAs play crucial roles in regulating gene expression, maintaining chromatin structure, and influencing various cellular processes, despite not being translated into proteins. Their involvement in essential biological functions connects them to both RNA structure and the classification of different types of RNA.

5 Must Know Facts For Your Next Test

1. lncRNAs are involved in a variety of cellular processes including transcriptional regulation, chromatin remodeling, and post-transcriptional processing.
2. They can act as scaffolds for protein complexes, helping to bring different proteins together to perform specific functions within the cell.
3. lncRNAs can interact with DNA, RNA, and proteins, influencing gene expression at multiple levels through mechanisms like epigenetic regulation.
4. Many lncRNAs are tissue-specific and can play roles in development and differentiation by regulating genes that are crucial at specific stages.
5. Altered expression of lncRNAs has been implicated in various diseases, including cancer, highlighting their importance in health and disease.

Review Questions

• What role do long non-coding RNAs (lncRNAs) play in gene regulation, and how might they interact with other biomolecules?
  • Long non-coding RNAs (lncRNAs) play a significant role in gene regulation by influencing transcriptional activity and chromatin structure. They can interact with DNA sequences, other RNAs, and proteins to form complexes that either promote or inhibit gene expression. For example, lncRNAs can recruit chromatin-modifying enzymes to specific genomic locations, thereby altering the accessibility of DNA for transcription factors and ultimately affecting the expression of target genes.
• Compare the functions of long non-coding RNAs (lncRNAs) with those of messenger RNAs (mRNAs) in cellular processes.
  • Long non-coding RNAs (lncRNAs) and messenger RNAs (mRNAs) have fundamentally different functions in cellular processes. While mRNAs serve as templates for protein synthesis by conveying genetic information from DNA to ribosomes, lncRNAs do not encode proteins. Instead, lncRNAs are involved in regulating gene expression through various mechanisms such as chromatin modification and transcriptional interference. This distinction highlights the broader regulatory roles of lncRNAs compared to the more direct role of mRNAs in protein production.
• Evaluate the implications of altered lncRNA expression in disease contexts such as cancer. What does this suggest about their potential as therapeutic targets?
  • Altered expression of long non-coding RNAs (lncRNAs) has been implicated in various diseases, particularly cancer, where they can contribute to tumorigenesis by dysregulating gene expression and cellular pathways. This suggests that lncRNAs could serve as potential therapeutic targets or biomarkers for cancer diagnosis and treatment. By understanding how specific lncRNAs influence disease processes, researchers can develop strategies to manipulate their expression or function, potentially leading to novel therapies aimed at restoring normal cellular regulation and combating disease progression.

Related terms

Messenger RNA (mRNA): A type of RNA that serves as a template for protein synthesis, carrying genetic information from DNA to the ribosome.

Small interfering RNA (siRNA): Short, double-stranded RNA molecules that play a key role in the RNA interference pathway, regulating gene expression by targeting mRNA for degradation.

Ribosomal RNA (rRNA): The type of RNA that, along with proteins, makes up the ribosomes, which are essential for protein synthesis in all living cells.