Differential subcellular localization of Ror tyrosine kinase receptors in cultured astrocytes.

Ror1 and Ror2 belong to a family of tyrosine kinase receptors that are highly conserved among species. They are expressed throughout the organism, including the central nervous system. In the present study, we analyzed the expression and subcellular localization of Ror1 and Ror2 in astrocytes by means of reverse transcription-polymerase chain reaction, Western blot analysis, and immunocytochemistry. Our results indicated that both Ror1 and Ror2 are readily detectable in cultured astrocytes. They also showed that Ror1 and Ror2 are associated with different components of the cytoskeleton. While Ror1 co-localized with F-actin along stress fibers, Ror2 partially co-localized with microtubules. In addition, our results suggest that Ror1 and Ror2 undergo different posttranslational modifications in cultured astrocytes. Ror1 is highly glycosylated in these cells. In contrast, no glycosylation was detected in Ror2. Taken together, these results suggest distinct roles for these tyrosine kinase receptors in astrocytes.