The intracellular dynamic of protein palmitoylation

Salaun, Christine; Greaves, Jennifer; Chamberlain, Luke H.

The suggestion that palmitoylation of newly synthesized peripheral proteins is a Golgi-specific event is largely consistent with previously published data. Although DHHC palmitoyl transferases associate with a range of organelles, including the ER, Golgi, and plasma membrane (Ohno et al., 2006; Greaves et al., 2010) , independent analyses of DHHC substrate pairs have returned a high percentage of Golgi DHHC proteins as positive hits (Fukata et al., 2004 Huang et al., 2004; Fernández-Hernando et al., 2006; Greaves et al., 2008 Greaves et al., , 2010 Tsutsumi et al., 2009) . Indeed, DHHC9 displays specificity toward H-and N-Ras (Swarthout et al., 2005) and is Golgi localized (Swarthout et al., 2005) . However, Rocks et al. (2010) argued against any rigid requirements for DHHC substrate specificity and reported that DHHC9 knockdown (at the mRNA level at least) did not affect the intracellular localization of H-Ras or recovery kinetics after photobleaching of Golgi-localized H-Ras. To examine more closely whether the palmitoylation domain of N-Ras contained a recognition motif for interaction with specific DHHC proteins, the amino acids around the Rocks et al. (2010) did not report association of microinjected Ras proteins with recycling endosomes, and it will be important to clarify this apparent discrepancy between these studies.