ROLE OF GPAT2 IN THE LANDSCAPE OF SMALL NON-CODING RNAs IN BREAST CANCER CELLS

LACUNZA E; MONTANARO MA; SALVATI A; MEMOLI D; RIZZO F; ABBA MC; GONZALES BARO MR; WEISZ A; PELLON MAISON M

Congreso; REUNIÓN CONJUNTA DE SOCIEDADES DE BIOCIENCIAS; 2017

Abstract GPAT2 is expressed in the testis and ectopically overexpressedin cancer cells, where it contributes to tumoral phenotype.Although GPAT2 was initially linked to lipid metabolism, it wasdemonstrated that it is essential for primary piRNA biogenesis. Inthis work, we analyzed the impact of GPAT2 silencing in the landscapeof small noncoding RNAs of MDAMB231 cells. From the differentiallyexpressed (DE) piRNAs, we found that most downregulated(down) piRNAs (32/39, 82%) are single copy in the genomebeing mainly intragenic (27/32, 84%), whereas upregulated (up)piRNAs are single (18/38, 47%) and multiple (20/38, 52%) copiesin a similar way. Interestingly, snoRNAs constituted the host geneof 81% of the intragenic single copy down piRNAs, which means56% of total down piRNAs. Furthermore, many of down piRNAswere previously found upregulated in breast cancer growing cells.From the DE tRFs we identified 147 down and 128 up. Down tRFswould be derived from ?differentiation tRNAs? whereas up tRFswould be from ?proliferation tRNAs?. Moreover, we obtained a proteinprofile from the amino acids carrying by DE tRFs and identifiedproteins associated to phosphatidic acid biosynthesis, phospholipidacyl chain remodeling and regulation of cell death. We also found asignificant difference (p