Mlp2p, a component of nuclear pore attached intranuclear filaments, associates with Nic96p

A fraction of the yeast nucleoporin Nic96p is localized at the terminal rin g of the nuclear basket. When Nic96p was affinity purified from glutaraldeh yde-treated spheroplasts, it was found to be associated with Mlp2p. Mlp2p, together with Mlp1p, are the yeast Tpr homologues, which form the nuclear p ore attached intranuclear filaments (Strambio-de-Castillia, C., Blobel, G., and Rout, M. P. (1499) J. Cell Biol. 144, 839-855). Double disruption muta nts of MLP1 and MLP2 are viable and apparently not impaired in nucleocytopl asmic transport. However, overproduction of MLP1 causes nuclear accumulatio n of poly(A)(+) RNA in a chromatin-free area of the nucleus.