IGF-2

IGF-2 is a member of the insulin family of polypeptide growth factors that is involved in development and growth. It is an imprinted gene and is expressed only from the paternally inherited allele. It is a candidate gene for eating disorders. There is a read-through, INS-IGF2, which aligns to this gene at the 3′ region and to the upstream INS gene at the 5′ region. Two alternatively spliced transcript variants encoding the same protein have been found for this gene.

Insulin-like growth factor II, also known as IGF-II, Somatomedin-A and IGF2, is a secreted protein which belongs to the insulin family. The insulin family, comprised of insulin, relaxin, insulin-like growth factors I and II ( IGF-I and IGF-II ) and possibly the beta-subunit of 7S nerve growth factor, represents a group of structurally related polypeptides whose biological functions have diverged. The IGFs, or somatomedins, constitute a class of polypeptides that have a key role in pre-adolescent mammalian growth. The IGFs possess growth-promoting activity.

They are potent mitogens for cultured cells. IGF-I expression is regulated by growth hormone and mediates postnatal growth, while IGF-II appears to be induced by placental lactogen during prenatal development. IGF2 / IGF-II is perhaps the most intricately regulated of all growth factors characterized to date. IGF2 / IGF-II activity is controlled through differential expression of receptors and IGF-binding proteins (IGFBPs) that determine protein availability. IGF2 / IGF-II is influenced by placental lactogen and may play a role in fetal development. Genetic variations in IGF2 are associated with body mass index (BMI). BMI is a statistical measurement which compares a person’s weight and height.

References
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