CELLULAR FATE OF PHOSPHOLIPIDS (PL) SYNTHESIZED DURING G2/M

RODRIGUEZ SAWICKI, LUCIANA; MOSCOSO, VERONICA; VES LOSADA, ANA; CORSICO, BETINA; SCAGLIA, NATALIA

Cordoba

Congreso; LII Reunión Anual de la Sociedad Argentina de Investigación Bioquímica y Biología Molecular (SAIB); 2016

SAIB

Cell division ends with the reassemble of the nuclear envelope and separation of daughter cells, process that requires dynamic changes in the distribution and composition of membrane PL. We previously found that lysoPL levels decrease drastically from G2/M to G1 phase, while de novo phosphatidylcholine synthesis increases, suggesting an enhanced membrane production concomitant with a decrease in its turnover. In addition, fatty acid synthesis and incorporation into membranes increases upon cell division. Thus, our aim is to study the cellular fate of synthesized PL during G2/M. We synchronized HeLa cells to study lipid synthesis during G2/M. Metabolic labeling with 14C-acetate and separation of subcellular fractions with a sucrose gradient allowed us to determine the distribution of incorporated label into lipids during cell division. We also used the choline analog propargylcholine (p-Cho) to assess the fate of newly synthesized PL in G2/M. The resulting labeled PL molecules were visualized via a reaction with an azide-Alexa488. Incorporation of 14C-acetate and p-Cho labeling showed that lipids synthesized during G2/M localized in a region compatible with the nucleus and endoplasmic reticulum. These studies will contribute to the knowledge of the metabolic requirements during the cell cycle and could have implications for the treatment and diagnosis of hyperproliferative diseases.