PKD-dependent PARP12-catalyzed mono-ADP-ribosylation of Golgin-97 is required for E-cadherin transport from Golgi to plasma membrane

Abstract

Adenosine diphosphate (ADP)-ribosylation is a posttranslational modification involved in key regulatory events catalyzed by ADP-ribosyltransferases (ARTs). Substrate identification and localization of the mono-ADP-ribosyltransferase PARP12 at the trans-Golgi network (TGN) hinted at the involvement of ARTs in intracellular traffic. We find that Golgin-97, a TGN protein required for the formation and transport of a specific class of basolateral cargoes (e.g., E-cadherin and vesicular stomatitis virus G protein [VSVG]), is a PARP12 substrate. PARP12 targets an acidic cluster in the Golgin-97 coiled-coil domain essential for function. Its mutation or PARP12 depletion, delays E-cadherin and VSVG export and leads to a defect in carrier fission, hence in transport, with consequent accumulation of cargoes in a trans-Golgi/Rab11–positive intermediate compartment. In contrast, PARP12 does not control the Golgin-245–dependent traffic of cargoes such as tumor necrosis factor alpha (TNFα). Thus, the transport of different basolateral proteins to the plasma membrane is differentially regulated by Golgin-97 mono-ADP-ribosylation by PARP12. This identifies a selective regulatory mechanism acting on the transport of Golgin-97– vs. Golgin-245–dependent cargoes. Of note, PARP12 enzymatic activity, and consequently Golgin-97 mono-ADP-ribosylation, depends on the activation of protein kinase D (PKD) at the TGN during traffic. PARP12 is directly phosphorylated by PKD, and this is essential to stimulate PARP12 catalytic activity. PARP12 is therefore a component of the PKD-driven regulatory cascade that selectively controls a major branch of the basolateral transport pathway. We propose that through this mechanism, PARP12 contributes to the maintenance of E-cadherin–mediated cell polarity and cell–cell junctions.

Medicinal Chemistry Perspective on Targeting Mono-ADP-Ribosylating PARPs with Small Molecules

“… 141 PARP12 ADP-ribosylates Golgin-97 thereby regulates the basolateral transport of proteins. 142 The function of PARP12 in cancer remains highly controversial. While a deficiency of PARP12 in HCC was found to be associated with a promotion of migration and invasion of HCC, 143 in other tumors it seems to be highly upregulated.…”

Endogenous and Exogenous Regulatory Signaling in the Secretory Pathway: Role of Golgi Signaling Molecules in Cancer

“…As mentioned above, PKD activation regulates PARP12 dependent ADP-rybosilation of Golgin 97 on TGN membranes ( Grimaldi et al, 2022 ), and both PARP12 and Golgin97 have clear roles in cancer. Indeed, low Golgin97 expression has been correlated with increased invasiveness and poor survival in breast cancer patients, and Golgin97 depletion in breast cancer cell lines leads to hyper-activation of NF-kB and reduced IκBα, thus promoting migration and invasion ( Hsu et al, 2018 ).…”

“…PAK1 and PAK4 are localized on TGN membranes and are required for the formation of post-Golgi carriers containing basolateral cargoes, and BARS is one of the PAKs substrates on the TGN ( Valente et al, 2012 ). More recently, PKD action on regulating basolateral proteins transport has further expanded, thanks to the identification of PARP12 as a novel TGN localized substrate ( Grimaldi et al, 2022 ). Indeed, PARP12 catalyzes the specific ADP-rybosilation of Golgin97 during TGN export of important basolateral proteins, such as E-cadherin.…”

“…Indeed, PARP12 catalyzes the specific ADP-rybosilation of Golgin97 during TGN export of important basolateral proteins, such as E-cadherin. PKD-dependent PARP12 phosphorylation has a role in regulating this signaling network ( Grimaldi et al, 2022 ). Activated PKD is involved in several pathways on the Golgi complex, not only for the export of basolateral proteins ( Malhotra and Campelo, 2011 ) but also for the entry into mitosis by driving Golgi fragmentation in the G2 phase of the cell cycle ( Kienzle et al, 2013 ).…”

ADP-Ribosylation Post-Translational Modification: An Overview with a Focus on RNA Biology and New Pharmacological Perspectives

“…Reversible ADPr reaction regulates a plethora of fundamental biological processes in mammals, as diverse as DDR [26,[122][123][124][125][126], transcription, cell division [62,64,127], cell proliferation [128][129][130], cell death [131][132][133][134] immune and stress responses [76,77], as well as other emerging pathways [78,135,136]. For further details on the functional outcomes modulated by ADPr, we refer the reader to the valuable and specialized reviews in the field [24,26,[137][138][139][140][141][142].…”