The slow Wallerian degeneration protein, WldS, binds directly to VCP/p97 and partially redistributes it within the nucleus.
Slow Wallerian degeneration (Wld(S)) mutant mice express a chimeric nuclear protein that protects sick or injured axons from degeneration. The C-terminal region, derived from NAD(+) synthesizing enzyme Nmnat1, is reported to confer neuroprotection in vitro. However, an additional role for the N-terminal 70 amino acids (N70), derived from multiubiquitination factor Ube4b, has not been excluded. In wild-type Ube4b, N70 is part of a sequence essential for ubiquitination activity but its role is not understood. We report direct binding of N70 to valosin-containing protein (VCP; p97/Cdc48), a protein with diverse cellular roles including a pivotal role in the ubiquitin proteasome system. Interaction with Wld(S) targets VCP to discrete intranuclear foci where ubiquitin epitopes can also accumulate. Wld(S) lacking its N-terminal 16 amino acids (N16) neither binds nor redistributes VCP, but continues to accumulate in intranuclear foci, targeting its intrinsic NAD(+) synthesis activity to these same foci. Wild-type Ube4b also requires N16 to bind VCP, despite a more C-terminal binding site in invertebrate orthologues. We conclude that N-terminal sequences of Wld(S) protein influence the intranuclear location of both ubiquitin proteasome and NAD(+) synthesis machinery and that an evolutionary recent sequence mediates binding of mammalian Ube4b to VCP.
Laser
Heike
H
Institute for Genetics and Center for Molecular Medicine, University of Cologne, D-50674 Cologne, Germany.
Conforti
Laura
L
Morreale
Giacomo
G
Mack
Till G M
TG
Heyer
Molly
M
Haley
Jane E
JE
Wishart
Thomas M
TM
Beirowski
Bogdan
B
Walker
Simon A
SA
Haase
Georg
G
Celik
Arzu
A
Adalbert
Robert
R
Wagner
Diana
D
Grumme
Daniela
D
Ribchester
Richard R
RR
Plomann
Markus
M
Coleman
Michael P
MP
D000251:Adenosine Triphosphatases; D000595:Amino Acid Sequence; D000818:Animals; D019556:COS Cells; D018797:Cell Cycle Proteins / Q000737:chemistry / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism*; D002478:Cells, Cultured; D002522:Chlorocebus aethiops; D019143:Evolution, Molecular; D006367:HeLa Cells; D006801:Humans; D042581:Intranuclear Space / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000737:chemistry / Q000378:metabolism*; D009612:Nicotinamide-Nucleotide Adenylyltransferase / Q000378:metabolism; D011485:Protein Binding; D021381:Protein Transport; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D025801:Ubiquitin / Q000378:metabolism; D000074405:Valosin Containing Protein
D018797:Cell Cycle Proteins; D009419:Nerve Tissue Proteins; D011993:Recombinant Fusion Proteins; D025801:Ubiquitin; C442580:Wld protein, mouse; D009612:Nicotinamide-Nucleotide Adenylyltransferase; C510972:Nmnat1 protein, mouse; D000251:Adenosine Triphosphatases; C000614178:VCP protein, human; D000074405:Valosin Containing Protein; C000614179:Vcp protein, mouse; C000614180:Vcp protein, rat