WASP homologue-associated protein with actin, membranes and microtubules (WHAMM) contains three domains, an N-terminal domain that mediates Golgi membrane association, a coiled-coil region that binds microtubules, and one or two WH2 domains that stimulate Arp2/3-mediated actin polymerisation. It acts as a nucleation-promoting factor (NPF) that stimulates Arp2/3-mediated actin polymerisation both at the Golgi apparatus and along tubular membranes. It is involved as a regulator of Golgi positioning and morphology. It also participates in vesicle transport between the reticulum endoplasmic and the Golgi complex [].
JMY (junction-mediating and -regulatory protein) []and WHAMM (WASP homologue-associated protein with actin, membranes and microtubules) []are two nucleation-promoting factors (NPFs) with similar domain architecture. JMY was originally identified as a transcriptional co-factor in the p53-response to DNA damage. Aside from this nuclear function, JMY is involved in cytoskeleton remodelling and trans-Golgi transport []. WHAMM binds microtubules and is involved in ER to cis-Golgi transport []. JMY and WHAMM show similar localisation and could be involved in similar processes []. This middle domain is the coiled-coil region that putatively binds microtubules to the scaffold. This ability to interact with microtubules plays a role in membrane tubulation.
This is the N-terminal domain of WHAMM (WASP homologue-associated protein with actin, membranes and microtubules) and JMY (junction-mediating and -regulatory protein), two nucleation-promoting factors (NPFs) with similar domain architecture []. The function of this conserved region is not known; there are two highly conserved tryptophan residues.
