IGHV

Overview

Insulin-like Growth Factor 2 (IGF2) is a protein that in humans is encoded by the IGF2 gene. It is a member of the insulin-like growth factor family, which is involved in growth and development. IGF2 plays a crucial role in fetal development and continues to have significant functions in adults, particularly in cell growth and cell differentiation.

Structure

IGF2 is a small protein with a molecular weight of approximately 7.5 kDa. It shares structural similarities with insulin and IGF1, consisting of a single chain of 67 amino acids. The protein is synthesized as a larger precursor that undergoes proteolytic processing to yield the mature form.

Function

IGF2 is primarily involved in prenatal development, where it promotes cell proliferation and tissue growth. It acts by binding to the IGF1 receptor (IGF1R) and the insulin receptor (IR), as well as the IGF2/mannose-6-phosphate receptor (IGF2R), which is thought to mediate its degradation rather than signal transduction.

IGF2 is also implicated in metabolic regulation, muscle growth, and neurodevelopment. In adults, it continues to play a role in tissue repair and regeneration.

Regulation

The expression of IGF2 is tightly regulated by genomic imprinting, a genetic phenomenon where only one allele of a gene is expressed while the other is silenced. In the case of IGF2, the paternal allele is typically active, while the maternal allele is silenced. This imprinting is controlled by the H19/IGF2 imprinting control region.

Clinical Significance

Abnormal expression of IGF2 is associated with several diseases. Overexpression of IGF2 is linked to cancer, including Wilms' tumor, hepatoblastoma, and rhabdomyosarcoma. It is also involved in Beckwith-Wiedemann syndrome, a disorder characterized by overgrowth and an increased risk of tumor development.

Conversely, reduced IGF2 activity can lead to growth deficiencies and developmental disorders. Understanding the role of IGF2 in these conditions is crucial for developing targeted therapies.

Research and Therapeutic Potential

Research into IGF2 continues to explore its potential as a therapeutic target. Modulating IGF2 activity could have implications for treating cancer, growth disorders, and metabolic diseases.

Also see

• Insulin-like Growth Factor 1
• Genomic Imprinting
• Growth Hormone
• Cell Signaling
• Cancer Biology