Differentially Expressed MiRNAs In The Radiation-injuried Retinal Ganglion Cells And Predictions Of The Target Genes

[Objectives] To study the X-ray of different doses on the survival of RGCs; To screen priamarily different expressions of the miRNAs after X-ray radiation and predict their target genes.[methods] The RGCs which growed24h are radiated by the X-ray of OGy,2Gy,4Gy,6Gy,8Gy.Observe the cell density and morphology changes under the microscope daily. MTT evaluates the cell survival rate of each group. Detect the different expressions of miRNAs between6Gy and OGy radiation group by miRNA array.Use qRT-PCR to test the accuracy of the miRNA array.Apply the target gene predictation softwares of Targetscan and microRNAorg to predict the target genes of the five miRNAs which changed obviously.[Results] The cell density and morphology of different X-ray irradiation groups had no significant difference in the first4days. On the fifth day, the cell densities of the4Gy,6Gy and8Gy irradiation groups are lower and the cell morphology changed.MTT showed that the survival rate of the4Gy,6Gy and8Gy irradiation groups is lower statistically (p<0.01). miRNA array showed that37miRNAs differentially expressed in the6Gy irradiation group, of which16species increased and31species decresed.6miRNAs (miR-192,-34a*,-877,-34c,-34a,-22) increased more than1.5times and6miRNAs(miR-212,-338,-219-5p,-503,-210,-505)decreased to0.667times below. RT-PCR testified that the results of miRNA array is reliable. The predicted target genes of the five miRNAs involved in the processes of cell growth, development, appreciation, apoptotic and anti-apoptotic.[Conclusions] The X-ray of4Gy,6Gy,8Gy can cause the RGCs injuried; The X-ray of6Gy can cause the different expressions of some miRNAs; The miRNAs that differentially expressed in6Gy radiation group involved in the mechanism of injury in RGCs by regulatting the target genes.