Quantifying promoter-specific Insulin-like Growth Factor 1 gene expression by interrogating public databases.

Area of Science:

• Genomics
• Molecular Biology
• Comparative Biology

Background:

• Insulin-like growth factor 1 (IGF1) is crucial for growth, regeneration, and repair.
• IGF1 gene regulation is complex, influenced by hormones, nutrition, and tissue-specific factors.
• Quantifying IGF1 expression is challenging due to promoter variability and lack of standardized analysis platforms.

Purpose of the Study:

• To quantify IGF1 mRNA levels in human and macaque tissues using public RNA-sequencing data.
• To compare IGF1 gene expression patterns between humans and macaques.
• To assess the relative activity of IGF1's two promoters.

Main Methods:

• Utilized publicly accessible RNA-sequencing libraries for gene expression analysis.
• Focused on human and macaque species due to conserved IGF1 gene organization.
• Measured steady-state levels of IGF1 messenger RNAs (mRNAs).

Main Results:

• IGF1 transcripts showed high expression in adipose (fat) and liver tissues in both species.
• IGF1 expression was induced during human adipocyte differentiation.
• IGF1 mRNA levels increased in macaque skeletal muscle following dietary changes.
• IGF1 promoter 1 demonstrated significantly higher activity than promoter 2 across examined tissues.

Conclusions:

• Interrogating large-scale public genomic resources is an effective strategy for quantifying gene expression.
• IGF1 plays a significant role in metabolic tissues like fat and liver.
• Comparative analysis of IGF1 expression in humans and macaques reveals conserved patterns and species-specific responses.