title: A role of histone H3 lysine 4 methyltransferase components in endosomal trafficking.
abstract: Histone lysine methyltransferase complexes are essential for chromatin organization and gene regulation. Whether any of this machinery functions in membrane traffic is unknown. In this study, we report that mammal Dpy-30 (mDpy-30), a subunit of several histone H3 lysine 4 (H3K4) methyltransferase (H3K4MT) complexes, resides in the nucleus and at the trans-Golgi network (TGN). The TGN targeting of mDpy-30 is mediated by BIG1, a TGN-localized guanine nucleotide exchange factor for adenosine diphosphate ribosylation factor GTPases. Altering mDpy-30 levels changes the distribution of cation-independent mannose 6-phosphate receptor (CIMPR) without affecting that of TGN46 or transferrin receptor. Our experiments also indicate that mDpy-30 functions in the endosome to TGN transport of CIMPR and that its knockdown results in the enrichment of internalized CIMPR and recycling endosomes near cell protrusions. Much like mDpy-30 depletion, the knockdown of Ash2L or RbBP5, two other H3K4MT subunits, leads to a similar redistribution of CIMPR. Collectively, these results suggest that mDpy-30 and probably H3K4MT play a role in the endosomal transport of specific cargo proteins.
authors: Department of Molecular, Cellular, and Developmental Biology, University of California, Santa Barbara, Santa Barbara, CA 93106, USA.
authors: Zhuojin
authors: Z
authors: Xu
authors: Qiang
authors: Q
authors: Gong
authors: Bin
authors: B
authors: Xia
authors: Benjamin
authors: B
authors: Groves
authors: Marc
authors: M
authors: Zimmermann
authors: Chris
authors: C
authors: Mugler
authors: Dezhi
authors: D
authors: Mu
authors: Brian
authors: B
authors: Matsumoto
authors: Matthew
authors: M
authors: Seaman
authors: Dzwokai
authors: D
authors: Ma
mesh_terms: D000818:Animals; D001692:Biological Transport; D019556:COS Cells; D002478:Cells, Cultured; D002522:Chlorocebus aethiops; D011992:Endosomes / Q000378:metabolism*; D006367:HeLa Cells; D011495:Histone-Lysine N-Methyltransferase / Q000378:metabolism*; D006801:Humans; D051381:Rats
chemical_list: D011495:Histone-Lysine N-Methyltransferase