Protein depalmitoylases.

Area of Science:

• Biochemistry
• Molecular Biology
• Cell Biology

Background:

• Protein depalmitoylation involves removing fatty acids from proteins, primarily at cysteine residues.
• Acyl protein thioesterases (APT1 and APT2) and ABHD17 hydrolases are key enzymes involved in depalmitoylation.
• These enzymes play roles in signaling pathways, protein localization, and cell organization.

Purpose of the Study:

• To review the biochemical, structural, and cellular analyses of protein depalmitoylases.
• To highlight distinct roles of APT enzymes in growth factor and hormonal signaling.
• To identify opportunities for future research, including systems-wide analysis.

Main Methods:

• Biochemical assays to identify enzyme activity.
• Development of isoform-selective APT inhibitors.
• Analysis of crystal structures of APT1 and APT2.
• Review of existing literature on protein depalmitoylation.

Main Results:

• APT1 and APT2, initially identified as G protein depalmitoylases, accept various protein and phospholipid substrates.
• Distinct roles for APT enzymes in signaling pathways have been reported using selective inhibitors.
• Convergent acyl binding channels in APT1 and APT2 suggest complex substrate selection mechanisms.
• ABHD17 family contributes to depalmitoylation of specific GTPases and synaptic proteins.

Conclusions:

• Enzymatic depalmitoylation is essential for balancing the palmitoylation cycle, ensuring efficient membrane targeting.
• Depalmitoylation may have broader roles in cellular signaling, growth, and organization.
• Further research, including systems-wide approaches, is needed to fully understand protein depalmitoylation.