Study On Expression Level Of Telomerase Genes And C-myc Gene In Three Different Chicken Cells

Recently,telomerase has become a hot issue in studies on the mechanism of tumorigenesis.Telomerase is a special DNA polymerase, mainly composed of TER and TERT.Telomerase is able to utilizes its own RNA template to synthesize telomerease repeat sequence to stabilize chromosome termini. TERT has catalysis effect as telomerase catalytic subunit.Most of researches suggested there are the relatively high telomerase activity in 90% of human cancer cells and 98% of continuous cell lines,but no telomerase activity was found in normal somaticytes.The oncogenic serotype I MDV can induces lymphoproliferative disorder and causes lymphoproliferative infiltration of internal organs, muscles and peripheral nerves and development of cancers.MD has gained popular attention from virologists,investigators and veterinarians as a study model for cancers because MDV is the first experiment-testable cancer-inductive herpesvirus which could be prevented by vaccine among human and animal cancer researches.However,in-depth researches on the mechanism of MD genesis were still deficient.Thus,the studies on telomerase activity and expression of relevant genes in MD tumor would be very important to elucidated the association between telomerase and MD.In present research we tested and analyzed telomerase activity in MDCC-MSB1, PBL and different embryonic day CEF with modifiedTRAP technique and the Bandscan software.The results showed that there is no telomerase activity in PBLs as a legitimate negative control,the 11th embryonic day CEF presented the highest telomerase activity within the homogeneous array,and the highest telomerase activity (approximately 98.7)can be measured in MDCC-MSB1 among those three types of cells.The cDNAs of TERT,chTER, GAPDH,c-myc were amplified by RT-PCR,their sequence ware analyzed with the BLAST software and in GENBANK and delivered 100% homology.The results of the expression level of c-myc,chTERT and chTER in PBL,CEF and MDCC-MsB1 tested with the fluorescent relative quantity RT-PCR technique showed that the expression level of chTER was no significant difference in CEF and MDCC-MsB1 compare with in PBLs and were respectively 7 and 11 times, while c-myc and chTERT persented high-level expression in MDCC-MSB1 and were respectively 109 and 185 times of that in PBL.All those results suggested that advancing of telomerase activity probably associated with development of MD tumor.Expression level of chTER could not influence telomerase activity,However,chTERT was one of the limiting speed in telomerase activity,could influence telomerase activity.Meanwhile c-myc may regulated transcription of chTERT and chTER.Then expression level of c-myc associated with changing of telomerase activity.Therefore the detection of the expression of chTERT, chTER and c-myc at molecular level could promot the studies on the role of telomerase in MD and association between telomerase and human cancers.