Fig. 4
Anti-ST8SiaII-IB and anti-ST8SiaIV-IB mediates retention of ST8SiaII and ST8SiaIV inside the ER. 106 recombinant CHO cells transiently transfected for 48 h with the corresponding intrabody DNA or unspecific intrabody DNA in a 6-well microtiter plate were analyzed by immunofluorescence. a Colocalisation of IBs with ER marker Calnexin. Recombinant CHO cells expressing ST8SiaII (CHO-2A10 + 500) were transfected with anti-ST8SiaII-IB expression plasmid (upper line) or CHO cells expressing ST8SiaIV (CHO-2A10 + 418) were transfected with anti-ST8SiaIV-IB expression plasmid (lower line). ER resident marker Calnexin was stained red. IBs were labelled green. b colocalisation of ST8SiaII and ST8SiaIV in non transfected CHO-2A 10 + 500 cells (upper line) and in non transfected CHO-2A10 + 418 cells (lower line) with Golgi marker α-mannose II. Golgi marker α-mannose II was stained red. Polysialyltransferases were labeled green. c ST8SiaII and anti-ST8SiaII-IB or ST8SiaIV and anti-ST8SiaIV-IB were stained in anti-ST8SiaII-IB or ST8SiaIV-IB transfected CHO-2A10 + 500 cells or CHO-2A10 + 418 cells. In this case the polysialyltransferases were stained red d negative controls: Staining of the polysialyltransferases and IBs in the CHO cells transfected with the unspecific IBs. The experiment was done 3 times. Shown is a characteristic staining