High impact information on NUP53

• These changes allow a transport inhibitory nucleoporin, Nup53p, to bind the karyopherin Kap121p specifically during mitosis, slowing its movement through the NPC and inducing cargo release [1].
• Accompanying these events is the Nup53p-dependent hyperphosphorylation of Mad1p [2].
• By altering the expression of a single nucleoporin gene, NUP53, we showed that the overproduction of Nup53p altered nuclear transport and had a profound effect on the structure of the nuclear membrane [3].
• We also demonstrated that the targeting of excess Nup53p to the NPC and its specific association with intranuclear membranes were dependent on the karyopherin Kap121p and the nucleoporin Nup170p [3].
• At the nuclear envelope, the abilities of Nup53p to associate with the membrane and drive membrane proliferation were dependent on a COOH-terminal segment containing a potential amphipathic alpha-helix [3].

Biological context of NUP53

• Interestingly, Nup53p is specifically phosphorylated during mitosis [4].
• Karyopherins in nuclear pore biogenesis: a role for Kap121p in the assembly of Nup53p into nuclear pore complexes [5].

Anatomical context of NUP53

• Here, Nup53p induced the formation of intranuclear, tubular membranes that later formed flattened, double membrane lamellae structurally similar to the nuclear envelope [3].
• Vertebrate Nup53 interacts with the nuclear lamina and is required for the assembly of a Nup93-containing complex [6].

Physical interactions of NUP53

• The yeast nucleoporin Nup53p specifically interacts with Nic96p and is directly involved in nuclear protein import [7].

Other interactions of NUP53

• Kap121p can be released from Nup53p by the GTP bound form of the small GTPase Ran [4].
• By doing so, we identified the yeast nucleoporin Nup53p, which also exhibits multiple locations within the yeast NPC and colocalizes with Nic96p in all its locations [7].
• Whereas Nup53p is directly involved in NLS-mediated protein import by its interaction with the yeast nuclear import receptor Kap95p, it appears not to participate in NES-dependent nuclear export [7].

Analytical, diagnostic and therapeutic context of NUP53

• Strikingly, conventional and immunoelectron microscopy analysis revealed that excess Nup53p entered the nucleus and associated with the nuclear membrane [3].

References