Profiling Glutathionylome in CD38-Mediated Epithelial–Mesenchymal Transition

Protein S-glutathionylation is an
important post­translational
modification that regulates various cellular processes. However, changes
in glutathionylome in epithelial–mesenchymal transition (EMT),
a crucial cellular process for embryonic development, wound healing,
and carcinoma progression and metastasis, have not been fully characterized.
Our previous study revealed that CD38 overexpression decreased cellular
nicotinamide adenine dinucleotide (NAD+) levels and caused
cells to undergo EMT. In the present study, we engineered a cell system
in which the glutathione synthetase (GS) mutant was expressed that
catalyzed the formation of a glutathione analogue from azido-alanine
to profile changes of glutathionylome in CD38-overexpressing cells.
We identified 1298 glutathionylated proteins and revealed that proteins
with changed glutathionylation levels involved in EMT associated pathways
including epithelial adherens junction, actin cytoskeleton, and integrin
signaling. Moreover, the glutathionylation level of 15-hydroxy­prostaglandin
dehydrogenase (15-PGDH) was increased in CD38-overexpressing cells.
We further demonstrated that glutathionylation of Cys63 residue in
15-PGDH led to decreased enzymatic activity that could promote EMT
by increasing prostaglandin E2 (PGE2). Taken
together, these results indicate that the clickable glutathione is
an effective probe for glutathionylome profiling, and glutathionylation
of 15-PGDH on Cys63 inhibits its enzymatic activity to promote EMT.