Arabidopsis p24 delta 5 and p24 delta 9 facilitate Coat Protein I-dependent transport of the K/HDEL receptor ERD2 from the Golgi to the endoplasmic reticulum

作者：Carlos Montesinos Juan; Pastor Cantizano Noelia; Robinson David G; Jesus Marcote Maria; Aniento Fernando^*

来源：Plant Journal, 2014, 80(6): 1014-1030.

DOI：10.1111/tpj.12700

• Arabidopsisthaliana
• K
• HDEL receptor ERD2
• p24 proteins
• Coat Protein I
• Coat Protein II
• ER-Golgi transport
• Golgi-to-ER transport

The p24 proteins belong to a family of type I membrane proteins which cycle between the endoplasmic reticulum (ER) and Golgi via coat protein I (COPI) and COPII vesicles. Current nomenclature classifies them into four subfamilies, although plant p24 proteins belong to either the p24 or the p24 subfamilies. Here, we show that Arabidopsis p245/9 and HDEL ligands shift the steady-state distribution of the K/HDEL receptor ERD2 from the Golgi to the ER. We also show that p245/9 interact directly with ERD2. This interaction requires the Golgi dynamics (GOLD) domain in p245 and is much higher at acidic than at neutral pH, consistent with both proteins interacting at the cis-Golgi. In addition, p245 also inhibits the secretion of HDEL ligands, but not constitutive secretion, showing a role for p245 in retrograde Golgi-to-ER transport. Both p245 and ERD2 interact with ADP-ribosylation factor 1 (ARF1) and COPI subunits, mostly at acidic pH, consistent with COPI vesicles being involved in retrograde transport of both proteins. In contrast, both proteins interact with the COPII subunit Sec23, mostly at neutral pH, consistent with this interaction taking place at the ER for anterograde transport to the Golgi apparatus.

• 出版日期2014-12