ABSTRACT
Background:Bioinformatics is an effective technology for microarray data mining and gene function prediction. Aims:To analyze the gene CRELD2 that associated with pathogenesis,disease activity and efficacy of biological agents in ulcerative colitis( UC)by bioinformatics to provide a theoretical basis for subsequent studies on its biological function and molecular mechanism in the development and progress of UC. Methods:The microarray data associated with pathogenesis, disease activity and efficacy of biological agents in UC were downloaded from the Gene Expression Omnibus( GEO database);the data mining and analyses were conducted by using bioinformatics tools such as BRB-ArrayTools, ProtParam,ELM,SignalP 4. 1,PBIL-IBCP Lyon Gerland,GO and STRING. Results:Cross-over analyses revealed that expressions of four genes(CDC25B,CRELD2,IL1RN,PITPNC1)were up-regulated in the order from colonic mucosa of healthy subjects,un-inflamed mucosa of active UC patients to inflamed mucosa of active UC patients,meanwhile these four genes were significantly down-regulated in infliximab responders after treatment when compared with that before treatment and infliximab non-responders. The function of CRELD2 gene was unknown. Bioinformatics analyses showed that CRELD2 gene was located on the long arm of chromosome 22(22q13. 33),and encoded a secreted protein composed of 402 amino acids. This protein contained several epidermal growth factor( EGF)-like domains,mainly distributed in Golgi apparatus, endoplasmic reticulum and extracellular site and had calcium- and protein-binding effect. Interactions existed between CRELD2 and CHRNA4,CHRNB2 and RHBDD3 proteins. Conclusions:Gene CRELD2 may have EGF-like biological function and via participating directly or indirectly the regulation of immunocytes to affect the pathogenesis and disease activity of UC. It might be used as a biomarker for diagnosis and assessment of disease activity and therapeutic efficacy of UC. Furthermore,it might be a potential target for treatment of UC.