マツイ　ユウト   Yuuto Matsui   松井　優人    所属   川崎医科大学  医学部 基礎医学　微生物学    職種   助教
論文種別	研究論文（学術雑誌）
言語種別	英語
査読の有無	査読あり
表題	Endoplasmic reticulum-to-Golgi trafficking of procollagen III via conventional vesicular and tubular carriers
掲載誌名	正式名：Molecular Biology of the Cell 略　 称：Mol Biol Cell.
掲載区分	国外
巻・号・頁	33(3)
著者・共著者	Yukihiro Hirata, Yuto Matsui, Ikuo Wada, Nobuko Hosokawa
担当区分	2nd著者
発行年月	2022
概要	Collagen is the major protein component of the extracellular matrix. Synthesis of procollagens starts in the endoplasmic reticulum (ER), and three α chains form a rigid triple helix 300-400 nm in length. It remains unclear how such a large cargo is transported from the ER to the Golgi apparatus. In this study, to elucidate the intracellular transport of fibril-forming collagens, we fused cysteine-free GFP to the N-telopeptide region of procollagen III (GFP-COL3A1) and analyzed transport by live-cell imaging. We found that the maturation dynamics of procollagen III was largely different from that of network-forming procollagen IV. Proline hydroxylation of procollagen III uniquely triggered the formation of intralumenal droplet-like structures, similarly to events caused by liquid-liquid phase separation, and ER exit sites surrounded large droplets containing chaperones. Procollagen III was transported to the Golgi apparatus via vesicular and tubular carriers containing ERGIC53 and RAB1B; this process required TANGO1 and CUL3, which we previously reported to be dispensable for procollagen IV. GFP-COL3A1 and mCherry-α1AT were cotransported in the same vesicle. Based on these findings, we propose that shortly after ER exit, enlarged carriers containing procollagen III fuse to ERGIC for transport to the Golgi apparatus by conventional cargo carriers.