RELATIONSHIP BETWEEN RAB1 AND AUTOPHAGIC PATHWAY

BARRERA P, ZOPPINO FCM, MUNAFÓ D, GUTIERREZ M AND COLOMBO M

Mendoza Argentina

Congreso; XX Reunión Científica Anual Sociedad de Biología de Cuyo (SBC).; 2002

Sociedad de Biología de Cuyo

Autophagy is a process by which cytoplasmic proteins and organelles are sequestered into a membranous compartment,  autophagosome to be finally degraded by the lysosomes. This process contributes to the cellular homoeostasis under nutrient deprivated conditions, celullar differentation, aging and like apoptosis, it is a kind of programed cell death. Rab GTPases comprises a large family of proteins, localized in distinct subcellular compartments where they coordinate consecutive stages of membrane transport. Rab 1 is a member of this family who is essential for ER to Golgi. Recently, the yeast homologue of Rab1, Ypt1 has been related to the autophagic pathway. To study the role of Rab1 in autophagy, we stably transfected CHO cells with the GFP-Rab1 wt and mutants. Under control conditions Rab1wt and mutants colocalized with the Cis-Golgi markers. Surprisingly, after induction of autophagy by amino acid deprivation, Rab1 moved to vacuoles that do not colocalize with Golgi markers.  These vacuoles were labeled with monodansylcadaverine , a specific marker for autofagic vacuoles. These data suggest that Rab1 is related to autofagic pathway