Progress in the Studies of Eph subfamily Receptor Tyrosine Kinases.

Receptor tyrosine kinases (RTKs) are involved in many different processes including cellular growth,differentiation,embryonic development,oncogenesis and intracellular signalling pathways, thus possessing important physiological functions. There are now more than 50 distinct RTK genes that have been published and divided into 14 sub families ,the largest one known is the Eph sub family which is comprised of at least fifteen members. Some of the Eph family members are predominantly expressed in the developing brain, the others are expressed in a broader range of tissues. Recently the findings of the excellular ligands of this family should facilitate further studies of its function. The isolation, pattern of expression and the ligands of Eph like receptors are summarised.