Expression And Characterization Of A Novel Human Gene Ljg And Its Protein LJG

NF-κB, one of the most important transcription factors, regulates numerousgenes transcription and plays a key role in immune and inflammation response, cellsurvival, proliferation and cancer process. Through bioinformatic search, we found anew potential protein, temporarily named LJG, is possibly associated with NF-κB.I have checked up the transcription level of LJG gene in several tumor cells(including U937, Hela and MCF-7, etc) and mice organizations (including liver,thymus and spleen, ect), and found that LJG in all experimental cells andorganizations are expressed. We cloned LJG from K562cell, which is randomlyselected, and constructed the expression vectors. In order to get the stability of LJGgene mRNA and protein,293T cells were transfected with the LJG-3HA vector, andresults showed that the half-times of LJG gene mRNA and protein are respectivelyabout2hours and2hours. In addition, the result also showed the LJG proteinmolecular weight is about28.7KDa. Through online software, I predicted the proteinmodification sites of LJG protein. The results showed that there are not anyN-glycosylation modification sites, but there may be13phosphorylated sites,5ubiquitin sites and11acetylated sites. I have found that LJG protein shows a nuclearlocalization with a speckled expression pattern, and its N terminal plays a veryimportant role in nuclear position.Through P-Match software, there may be a NF-κB binding site at3098upstreamof LJG gene transcription start site. But in U937cell LJG’s expression is constant inresponse to TNFα-or LPS-induced NF-κB activation. In addition, location andexpression level of LJG would not be changed in response to TNFα(≤40ng/mL)-induced NF-κB activation in293T cell. LJG upregulate the expression ofBfl1/A1, which doesn’t depend onTNFα/NF-κB signaling pathway.