Aim: To isolate and identify a human DnaJ homolog chaperon, PBP, from a human skeleton cDNA library, and to analyze its expression and distribution in transfected mammalian cells.
Methods: (32)p-dCTP labeled probe hybridization was used to screen the human skeleton cDNA library and sequence of the positive clones were analyzed. Then PBP gene was transfected into COS-7 cells using lipofectamin. PBP expressed in the cells were detected by Western-blot and indirect immunofluorescence staining.
Results: A full-length(1.5 kb) cDNA of peripherin-binding protein (PBP) was identified, which is identical with that of mrj. Full length PBP was mainly localized to cytoplasms of COS-7 cells in interphase, and to nuclei in mitosis.
Conclusion: The results indicate that besides cooperating with DnaK (HSP70), PBP itself plays an important role as a member of DnaJ family. PBP may also be involved in the regulation of cell cycle.