Differences in protein distribution of cells forming mineralized periodontal tissues

Cementoblasts and osteoblasts share several biological markers, and both form tissues whose inorganic component is hydroxyapatite.

OBJECTIVES: To characterize the Nuclear Speckle that is the phenotypic representation of the transcriptional activity of the cell, developed by a cascade of molecular events across the splicing for the maturation of pre-mRNA, and to analyze the distribution of 2 proteins involved in mineralization.

METHODS: We used antibodies against the Ser-Arg-rich (SR) proteins, CAP and CEMP1, and observed ultrastructure and immunolocalization by immunofluorescence and TEM.

RESULTS: Even though both types of cells showed a speckled pattern, both seemed to be different, suggesting that they have a characteristic transcriptional activity. In addition, we observed that the localization of CAP and CEMP1 occurred only in cementoblasts; CAP cytoplasm and CEMP1 were present in cytoplasmic dots and also showed signs in the nucleus. By TEM, we identified the proteins and fibro-granular material in the nuclear and nucleolar components.

CONCLUSION: We reported differences in transcriptional and processing activity of these cells by evaluating the morphology of intra-nuclear factors. Finally, CAP and CEMP1 are specific for cementoblasts and may play a role in cement mineralization and expression of this cellular line.