Objective:To explore the molecular mechanism of over-expression of Proline-rich protein 11(PRR11)gene inducing abnormal chromatin condensation. Methods:The PRR11 gene was down-regulated and over-expressed using si RNA transient over-expression and immunofluorescent staining in lung cancer cell A549. The expressions of the Vimentin at m RNA and protein levels were detected by RT-PCR and Western blot after the PRR11 treatment

respectively. Subcellular distribution of Vimentin and disruption of chromatin condensation was detected by immunofluorescence. Results:Endogenous PRR11 proteins were dispersively distributed in cytoplasm

and over-expressed Flag-PRR11 proteins were dispersively and reticularly arranged in cytoplasm. The results showed that both endogenous and exogenous over-expressed PRR11 proteins were co-localized with Vimentin. Disorder arrangement of Vimentin in the perinuclear area and disruption of chromatin condensation were observed after over expressing PRR11 proteins. Conclusion:The PRR11 proteins are co-localized with Vimentin

and the distribution of Vimentin proteins is re-arranged after forced expression of PRR11 proteins in lung cancer cell A549. We speculate that abnormal expression of PRR11 proteins could induce the instability of Lamins and abnormal chromatin condensation through co-localization with Vimentin and thereby promotes the development of tumor.