IGF-2 Human Active Protein

This gene encodes a member of the insulin family of polypeptide growth factors, which are involved in development and growth. It is an imprinted gene, expressed only from the paternal allele, and epigenetic changes at this locus are associated with Wilms tumour, Beckwith-Wiedemann syndrome, rhabdomyosarcoma, and Silver-Russell syndrome. A read-through INS-IGF2 gene exists, whose 5' region overlaps the INS gene and the 3' region overlaps this gene. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Oct 2010]

Function: The insulin-like growth factors possess growth-promoting activity. In vitro, they are potent mitogens for cultured cells. IGF-II is influenced by placental lactogen and may play a role in fetal development. Ref.28Preptin undergoes glucose-mediated co-secretion with insulin, and acts as physiological amplifier of glucose-mediated insulin secretion. Exhibits osteogenic properties by increasing osteoblast mitogenic activity through phosphoactivation of MAPK1 and MAPK3. Ref.28

Subcellular location: Secreted.

Post-translational modification: O-glycosylated with core 1 or possibly core 8 glycans. Thr-96 is a minor glycosylation site compared to Thr-99. Ref.27 Ref.31 Ref.32

Polymorphism: Genetic variations in IGF2 are associated with body mass index (BMI). The BMI is a statistical measurement which compares a person's weight and height.

Involvement in disease: Silver-Russell syndrome (SRS) [MIM:180860]: A clinically heterogeneous condition characterized by severe intrauterine growth retardation, poor postnatal growth, craniofacial features such as a triangular shaped face and a broad forehead, body asymmetry, and a variety of minor malformations. The phenotypic expression changes during childhood and adolescence, with the facial features and asymmetry usually becoming more subtle with age.Note: The gene represented in this entry is involved in disease pathogenesis. Most of the cases of Silver-Russell syndrome are caused by the epigenetic changes of DNA hypomethylation at the telomeric imprinting control region (ICR1) on chromosome 11p15, involving the H19 and IGF2 genes. Ref.29

Sequence similarities: Belongs to the insulin family.

Mass spectrometry: Molecular mass is 7469.4 Da from positions 25 - 91. Determined by MALDI. Ref.25 Ref.26Molecular mass is 7398.3 Da from positions 26 - 91. Determined by MALDI. Ref.25 Ref.26