Table I.

Proteins regulated by RanGTP during spindle assembly ^a

Protein	Function/activity	Localization	Activity regulated by RanGTP
TPX2a–j	MAP MT nucleation Spindle pole organization Targeting of Xklp2 and Aurora A Activation of Aurora A	Spindle poles and spindle MTs Midbody in telophase Degraded in G1	Binding to importins MT nucleation Interaction with Aurora A Activation of Aurora A
NuMAk–m	MAP Spindle pole organization	Spindle pole Nuclear matrix in interphase	Binding to importins
XCTK2n,o	Kinesin-like protein Minus end–directed motility Organization of spindle poles	Spindle poles and spindle MTs	Binding to importins Inhibitory effect of importins  on MT binding of the  nonmotor domain (assay  with purified components)
Eg5p–r	Kinesin-like protein Homotetramer Plus end–directed motility Centrosome separation Antiparallel microtubule interactions Maintenance of spindle bipolarity	Spindle poles and spindle MTs	MT organization
kide, s–v	Chromokinesin Plus end–directed motility Chromosome oscillations Metaphase chromosome alignment	Chromatin, spindle MTs	Inhibitory effect of importins  on MT binding
Aurora Af–j, w	Mitotic kinase Activated by TPX2 Known substrates: Eg5, TPX2, TACC	Spindle MTs centrosome	Binding to TPX2

^aWittmann et al., 2000; ^bGruss et al., 2001; ^cGruss et al., 2002; ^dGarrett et al., 2002; ^eTrieselmann et al., 2003; ^fKufer et al., 2002; ^gEyers et al., 2003; ^hTsai et al., 2003; ⁱEyers and Maller, 2004; ^jBayliss et al., 2003; ^kMerdes et al., 1996; ^lNachury et al., 2001; ^mWiese et al., 2001; ⁿ Walczak et al., 1997; ^oEms-McClung et al., 2004; ^p Sawin et al., 1992; ^q Blangy et al., 1995; ^rWilde et al., 2001; ^s Antonio et al., 2000; ^t Funabiki and Murray, 2000; ^u Yajima et al., 2003; ^v Levesque and Compton, 2001; ^w Nigg, 2001.