Protein kinase Darkener of apricot and its substrate EF1γ regulate organelle transport along microtubules

Abstract

Regulation of organelle transport along microtubules is important for proper distribution of membrane organelles and protein complexes in the cytoplasm. RNAi-mediated knockdown in cultured Drosophila S2 cells demonstrates that two microtubule-binding proteins, a unique isoform of Darkener of apricot (DOA) protein kinase, and its substrate, translational elongation factor EF1c, negatively regulate transport of several classes of membrane organelles along microtubules. Inhibition of transport by EF1c requires its phosphorylation by DOA on serine 294. Together, our results indicate a new role for two proteins that have not previously been implicated in regulation of the cytoskeleton. These results further suggest that the biological role of some of the proteins binding to the microtubule track is to regulate cargo transport along these tracks.

Non-translational Connections of eEF1B in the Cytoplasm and Nucleus of Cancer Cells

“…Drosophila eEF1Bγ is a substrate of LAMMER kinase (DOA) and can be phosphorylated by human kinase LAMMER/CLK2 (CLK2) as well (Fan et al, 2010). Importantly, DOA kinase and eEF1Bγ negatively regulated motor-mediated transport of membrane organelles along microtubules depending on the phosphorylation of Ser 294 in eEF1Bγ (Serpinskaya et al, 2014).…”

Analysis of eEF1Bγ interactome in the nuclear fraction of A549 human lung adenocarcinoma cells

“…HNRNPH1 and CD2AP participate in exosome trafficking [33,120]. It is worthy to mention that a role of eEF1Bγ in organelle transport has been shown [16,121]. eEF1Bγ was also co-immunoprecipitated with an essential component of ER-Golgi transport vesicles [122].…”

Mass-spectrometric and bioinformatic analysis of eEF1Bγ interactome in the cytoplasmic fraction of A549 cells

“…Literature data indicate that eEF1Bg may have connections with different types of cytoskeleton [12,13] and interact with viral components [14,15], it may be involved in transcription process [16][17][18] and oxidative stress response [19].…”