Distribution and shedding of the membrane phosphatidylserine during maturation and aging of erythroid cells

► We studied the phosphatidylserine (PS) distribution during RBC maturation and aging.► Blood, bone marrow and cultured human and murine erythroid cells were studied. ► PS externalization/shedding decreased during maturation but increased during aging. ► PS externalization and shedding were regulated by changes in the cellular Ca flux. ► We suggest that this redistribution plays a role in RBC maturation and senescence.