Proliferation and cell death in the midgut of the stingless bee Melipona quadrifasciata anthidioides (Apidae, Meliponini) during metamorphosis

This study quantitatively compared proliferation and cell death in the remodeling of the midgut epithelium in Melipona quadrifasciata anthidioides during metamorphosis to elucidate the renewal mechanism of the midgut in bees during postembryonic development. An anti-phosphohistone H3 antibody was used to mark mitotic cells. An apoptotic cell marking kit was used (Apo-TRACE®) to identify cells undergoing the process of cell death. The ultrastructural aspects of cell death were also analyzed. The highest proliferative and apoptotic rates were observed in pink-eyed pupae. An increased number of cells and rebuilding of regenerative cell nests at the end of metamorphosis is a consequence of cell division in black-eyed pupae because cell division occurs at this stage in the absence of apoptosis. During metamorphosis, midgut epithelial cell death in M . quadrifasciata anthidioides occurs as a result of apoptosis and autophagy.