Programmed Cell Death and Microspore Embryogenesis

Programmed cell death (PCD) occurs in the anther during in vivo micro-spore/pollen development. The first hallmarks are detected in the tapetum at meiosis and consist in progressive degeneration of organelles such as mitochondria, as well as DNA degradation into multiple of 180kpb fragments. This phenomenon radially extends in the anther sporophytic tissues and finally affects microspore/pollen at various stages of development depending upon species. PCD may infer with the process of microspore embryogenesis. Indeed, the inducing pre-treatment is performed using the whole anther during the process of microspore vacuolation. Thus the stress of pre-treatment may influence the triggering of PCD in both the anther tissues and the microspores and is likely involved in the competence of microspore to the process of microspore embryogenesis. These data are also discussed considering the regeneration of albino microspore derived plants in cereals.