title: Trans-Golgi protein p230/golgin-245 is involved in phagophore formation.
abstract: p230/golgin-245 is a trans-Golgi coiled-coil protein that is known to participate in regulatory transport from the trans-Golgi network (TGN) to the cell surface. We investigated the role of p230 and its interacting protein, microtubule actin crosslinking protein 1 (MACF1), in amino acid starvation-induced membrane transport. p230 or MACF1 knock-down (KD) cells failed to increase the autophagic flow rate and the number of microtubule-associated protein 1 light chain 3 (LC3)-positive puncta under starvation conditions. Loss of p230 or MACF1 impaired mAtg9 recruitment to peripheral phagophores from the TGN, which was observed in the early step of autophagosome formation. Overexpression of the p230-binding domain of MACF1 resulted in the inhibition of mAtg9 trafficking in starvation conditions as in p230-KD or MACF1-KD cells. These results indicate that p230 and MACF1 cooperatively play an important role in the formation of phagophore through starvation-induced transport of mAtg9-containing membranes from the TGN. In addition, p230 itself was detected in autophagosomes/autolysosome with p62 or LC3 during autophagosome biogenesis. Thus, p230 is an important molecule in phagophore formation, although it remains unclear whether p230 has any role in late steps of autophagy.
authors.affiliation: Division of Oral Biochemistry, Niigata University Graduate School of Medical and Dental Sciences, Chuo-ku, Niigata 951-8514, Japan.
authors.forename: Miwa
authors.initials: M
authors.lastname: Sohda
authors.affiliation: Department of Cell Biology, Fukuoka University School of Medicine, Jonan-ku, Fukuoka 814-0180, Japan. Electronic address: misumi@fukuoka-u.ac.jp.
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Misumi
authors.affiliation: Joint Laboratory for Frontier Medical Science, Fukuoka University School of Medicine, Jonan-ku, Fukuoka 814-0180, Japan.
authors.forename: Shigenori
authors.initials: S
authors.lastname: Ogata
authors.affiliation: Department of Internal Medicine, Fukuoka University School of Medicine, Jonan-ku, Fukuoka 814-0180, Japan.
authors.forename: Shotaro
authors.initials: S
authors.lastname: Sakisaka
authors.affiliation: Department of Pediatrics, Fukuoka University School of Medicine, Jonan-ku, Fukuoka 814-0180, Japan.
authors.forename: Shinichi
authors.initials: S
authors.lastname: Hirose
authors.affiliation: Fukuoka Tenjin Medical Rehabilitation Academy, Chuo-ku, Fukuoka 810-0001, Japan.
authors.forename: Yukio
authors.initials: Y
authors.lastname: Ikehara
authors.affiliation: Division of Oral Biochemistry, Niigata University Graduate School of Medical and Dental Sciences, Chuo-ku, Niigata 951-8514, Japan.
authors.forename: Kimimitsu
authors.initials: K
authors.lastname: Oda
mesh_terms: D000199:Actins / Q000378:metabolism; D001324:Autoantigens / Q000378:metabolism*; D001343:Autophagy; D001692:Biological Transport; D002462:Cell Membrane / Q000378:metabolism; D006056:Golgi Apparatus / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D008565:Membrane Proteins / Q000378:metabolism*; D008840:Microfilament Proteins / Q000378:metabolism*; D008870:Microtubules / Q000378:metabolism; D010588:Phagosomes / Q000378:metabolism; D010957:Plasmids / Q000378:metabolism; D021381:Protein Transport; D034741:RNA, Small Interfering / Q000378:metabolism
chemical_list: D000199:Actins; D001324:Autoantigens; C098772:GOLGA4 protein, human; C095003:MACF1 protein, human; D008565:Membrane Proteins; D008840:Microfilament Proteins; D034741:RNA, Small Interfering
keywords: Autophagy; Golgi; Immunochemistry; Membrane trafficking; siRNA