TY - JOUR AU - Bottone, M.G. AU - Santin, G. AU - Soldani, C. AU - Veneroni, P. AU - Scovassi, A.I. AU - Alpini, C. PY - 2012/01/20 Y2 - 2024/03/29 TI - Intracellular distribution of Tankyrases as detected by multicolor immunofluorescence techniques JF - European Journal of Histochemistry JA - Eur J Histochem VL - 56 IS - 1 SE - Letters to the Editor DO - 10.4081/ejh.2012.e4 UR - https://www.ejh.it/ejh/article/view/ejh.2012.e4 SP - e4 AB - Poly(ADP-ribose) polymerases are a family of enzymes that catalyze the conversion of NAD+ into ADP-ribose. Among them, Tankyrases have been found to bind to centrosome, mitotic spindle and microsome proteins, in the cytoplasm, and to telomeres in the nucleus, where they play a relevant role in telomere metabolism. However, their precise intracellular localization during interphase has not been so far fully elucidated. We investigated this aspect<em> in situ</em> by double immunofluorescence experiments using antibodies recognizing Tankyrases 1-2 or other proteins residing in specific organelles (Golgi apparatus, mitochondria, lysosomes, endoplasmic reticulum). We used HeLa cells as a model system <em>in vitro</em>, before and after treatment with either actinomycin D or etoposide, to also investigate the possible relocation of Tankyrases during apoptosis. We observed that Tankyrases are distributed both in the nucleus and in the cytoplasm; in this latter compartment, they were found to colocate with the Golgi apparatus but never with the mitochondria; a pool of Tankyrases also colocates with the endoplasmic reticulum and lysosomes. Interestingly, in cells with clear signs of apoptosis, Tankyrases were detectable in the cytoplasmic blebs: this suggests that they are not massively cleaved during apoptosis and persist in the largely heterogeneous apoptotic remnants which are known to contain components of cytoplasmic and nuclear origin. ER -