CDK5 phosphorylates NTRK2 (TRKB) on serine residue S479 (corresponds to S478 in mouse and rat Ntrk2). CDK5-mediated phosphorylation does not affect NTRK2-mediated activation of RAS, PLCgamma or PI3K signaling (Cheung et al. 2007, Lai et al. 2012). It was originally suggested that S479 phosphorylation was needed for NTRK2-mediated activation of CDC42, which plays a role in dendritic growth (Cheung et al. 2007), but the involvement of CDC42 was later disputed (Lai et al. 2012).
CDK5 activated by chemical long-term potentiation, independently of BDNF and NTRK2, can phosphorylate intracellular NTRK2 at S479 and promote its insertion into plasma membrane (Zhao et al. 2009), but S479 phosphorylation does not significantly affect NTRK2 localization in vivo (Lai et al. 2012).