The Tip Growth Defective1 S-Acyl Transferase Regulates Plant Cell Growth in Arabidopsis

The study identified the TIP GROWTH DEFECTIVE1 (TIP1) gene in Arabidopsis thaliana, which played a crucial role in plant cell growth, particularly affecting root hair growth. TIP1 encoded an ankyrin repeat protein with a DHHC Cys-rich domain, expressed in various plant tissues. It was found to have S-acyl transferase activity, similar to homologues in yeast and humans, which is important for protein modification affecting membrane association and signal transduction. The research demonstrated that TIP1 could bind palmitate and rescue defects in a yeast S-acyl transferase mutant, and that inhibiting acylation in Arabidopsis mimicked the mutant phenotype. This highlighted the essential role of S-acylation in normal plant cell growth and provided a tool for further understanding this lipid modification in plants.