During microsporogenesis, the microsporocyte (or microspore) plasma membrane plays multiple roles in pollen wall development, including callose secretion, primexine deposition, and exine pattern determination. However, plasma membrane proteins that participate in these processes are still not well
The sporopollenin precursors, as a general constituent of sexine, are synthesized in the tapetum and deposited on the pollen surface after transportation and processing. The polyketide synthase condenses the acyl-CoA into a hydroxyalkyl α-pyrone, which is predicted to be a component of the