The sequences featured in this family are similar to a region of human TPR protein (Swiss:P12270) and to yeast myosin-like proteins 1 (MLP1, Swiss:Q02455) and 2 (MLP2, Swiss:P40457). These proteins share a number of features; for example, they all have coiled-coil regions and all three are associated with nuclear pores [1,2,3]. TPR is thought to be a component of nuclear pore complex- attached intra-nuclear filaments [1], and is implicated in nuclear protein import [2]. Moreover, its N-terminal region is involved in the activation of oncogenic kinases, possibly by mediating the dimerisation of kinase domains or by targeting these kinases to the nuclear pore complex [2]. MLP1 and MLP2 are involved in the process of telomere length regulation, where they are thought to interact with proteins such as Tel1p and modulate their activity [4].

1: Identification of protein p270/Tpr as a constitutive component of the nuclear pore complex-attached intranuclear filaments. Cordes VC, Reidenbach S, Rackwitz HR, Franke WW; J Cell Biol 1997;136:515-529. PMID:9024684

2: Tpr, a large coiled coil protein whose amino terminus is involved in activation of oncogenic kinases, is localized to the cytoplasmic surface of the nuclear pore complex. Byrd DA, Sweet DJ, Pante N, Konstantinov KN, Guan T, Saphire AC, Mitchell PJ, Cooper CS, Aebi U, Gerace L; J Cell Biol 1994;127:1515-1526. PMID:7798308

3: Mlp2p, a component of nuclear pore attached intranuclear filaments, associates with nic96p. Kosova B, Pante N, Rollenhagen C, Podtelejnikov A, Mann M, Aebi U, Hurt E; J Biol Chem 2000;275:343-350. PMID:10617624

4: Myosin-like proteins 1 and 2 are not required for silencing or telomere anchoring, but act in the Tel1 pathway of telomere length control. Hediger F, Dubrana K, Gasser SM; J Struct Biol 2002;140:79-91. PMID:12490156