The
insulin receptor (IR) is a
transmembrane receptor that is activated by
insulin,
IGF-I,
IGF-II and belongs to the large class of
tyrosine kinase receptors. Metabolically, the insulin receptor plays a key role in the regulation of glucose homeostasis, a functional process that under degenerate conditions may result in a range of clinical manifestations including
diabetes and
cancer. Biochemically, the insulin receptor is encoded by a single
gene , from which
alternate splicing during transcription results in either IR-A or IR-B
isoforms. Downstream post-translational events of either isoform result in the formation of a proteolytically cleaved a and ß subunit, which upon combination are ultimately capable of homo or hetero-dimerisation to produce the ˜320 kDa disulfide-linked transmembrane insulin receptor.