H19

Definition

h19 is a long non-coding RNA gene located on chromosome 11 that plays a crucial role in the regulation of gene expression and is implicated in genomic imprinting. This gene is involved in various biological processes, including growth and development, and has been linked to several diseases, notably cancer. h19 is known for its parental imprinting, meaning it is expressed only from the maternal allele while the paternal allele is silenced.

5 Must Know Facts For Your Next Test

1. The h19 gene is primarily expressed during embryonic development and plays an essential role in cellular growth regulation.
2. h19 acts as a tumor suppressor and has been linked to several types of cancers, indicating its importance in cell growth and differentiation.
3. The expression of h19 is tightly regulated by epigenetic mechanisms, including DNA methylation and histone modifications.
4. h19 is located adjacent to the insulin-like growth factor 2 (IGF2) gene, which is paternally expressed and helps regulate growth.
5. Disruption of the imprinting of h19 can lead to developmental disorders such as Beckwith-Wiedemann syndrome.

Review Questions

• How does h19 demonstrate the concept of genomic imprinting?
  • h19 illustrates genomic imprinting by being exclusively expressed from the maternal allele while the paternal allele is silenced. This parent-specific expression affects various biological processes, highlighting how imprinting can influence developmental outcomes. The regulation of h19 through imprinting also shows how epigenetic mechanisms can determine gene activity based on parental origin.
• What are the implications of h19's role as a long non-coding RNA in the context of cancer biology?
  • As a long non-coding RNA, h19 plays a significant role in regulating gene expression related to growth and differentiation. Its function as a tumor suppressor means that alterations in h19 expression can contribute to cancer development. Understanding h19's regulatory pathways provides insights into potential therapeutic targets for cancer treatment, making it a crucial focus in cancer biology research.
• Evaluate the potential consequences of disrupted imprinting at the h19 locus on organismal development and health.
  • Disrupted imprinting at the h19 locus can lead to significant developmental consequences and health issues, such as Beckwith-Wiedemann syndrome. This condition is characterized by overgrowth and an increased risk for various tumors, indicating that proper regulation of h19 is vital for normal development. The evaluation of these consequences underscores the importance of genomic imprinting in maintaining balanced gene expression and preventing disease.

Related terms

Imprinting Control Region (ICR): A regulatory DNA region that controls the expression of imprinted genes, such as h19, ensuring that only one allele is active depending on its parental origin.

Genomic Imprinting: A genetic phenomenon where certain genes are expressed in a parent-of-origin-specific manner, leading to different phenotypic outcomes based on which parent contributed the allele.

Long Non-Coding RNA (lncRNA): A type of RNA that does not encode proteins but can regulate gene expression and play roles in various cellular processes.