This entry represents the microtubule-associated tumour suppressor (MTUS1) family, including AT2 receptor-interacting proteins (ATIPs) from mammals and Inner centromere Kin-I stimulator (ICIS) from Xenopus. The transcript variants of human MTUS1 gene can be classified into three major groups (ATIP1, ATIP3 and ATIP4) based on their tissue distribution and utilisation of its exons []. ATIP1, also known as MTSG1, interacts with the AT2 receptor and is involved in its activation. AT2 receptor could antagonise the effect of the AT1 receptor and generate anti-proliferative, anti-migratory and anti-inflammatory responses []. It may cooperate with AT2 to inactivate the receptor tyrosine kinases [].ATIP3 is a microtubule associated protein whose expression is diminished in breast cancer []. It localises at the mitotic spindle throughout mitosis and decorates the intercellular bridge during cytokinesis []. It is a homologue of the Xenopus ICIS protein, which is an inner centromere protein acting as a scaffold to bring the microtubule-depolymerising kinesins MCAK and Kif2A to the kinetochore []. ICIS may regulate kinesin depolymerase activity at the mitotic spindle and ensures proper chromosome segregation during mitosis []. ATIP4 may be involved in brain development and/or cognition [].
