Exosome secretion and red cell maturation: Exploring molecular components involved in the docking and fusion of multivesicular bodies in K562 cells.
During reticulocyte maturation, some membrane proteins and organelles that are not required in the mature red cell are lost. These proteins are released into the extracellular medium associated with vesicles present in multivesicular bodies (MVBs). Fusion of MVBs with the plasma membrane results in secretion of the small internal vesicles, termed exosomes. By studying MVBs fusion and exosome release in K562 cells, a human erythroleukemic cell line, we have determined the functional significance of Rab11 and calcium in these events. Additionally, in the transformation process that occurs during erythrocyte maturation, intracellular organelles are likely removed as a consequence of autophagic sequestration and degradation. We propose K562 cells as a useful tool to analyze, at the molecular level, the role of autophagy in the terminal differentiation of red cells.
Fader
Claudio M
CM
Laboratorio de Biología Celular y Molecular, Instituto de Histología y Embriología (IHEM)-CONICET, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Casilla de Correo 56, Centro Universitario, Parque General San Martín, 5500 Mendoza, Argentina.
Savina
Ariel
A
Sánchez
Diego
D
Colombo
María I
MI
D001343:Autophagy; D002118:Calcium / Q000502:physiology; D002454:Cell Differentiation; D011992:Endosomes / Q000378:metabolism* / Q000502:physiology; D004912:Erythrocytes / Q000166:cytology* / Q000648:ultrastructure; D005089:Exocytosis; D006801:Humans; D020014:K562 Cells; D008561:Membrane Fusion; D012156:Reticulocytes / Q000166:cytology / Q000648:ultrastructure; D020691:rab GTP-Binding Proteins / Q000502:physiology; D000099193:rab11 GTP-Binding Proteins
D002118:Calcium; D020691:rab GTP-Binding Proteins; D000099193:rab11 GTP-Binding Proteins