Researching Of Related Genes With Broiler Chickens Tibial Dyschondroplasia By CDNA Microarray Technology

Tibial dyschondroplasia (TD) is a kind of cartilage metabolism disease occured widely in poultry industry.TD disorder is characterized by the formation of noncalcified, nonvascularized,opaque white"cartilage wedge" that can extend from the epiphyseal growth plate into the metaphysic, mainly caused bone fractures and infections of broilers, turkeys. Due to the above characteristics of the disease, meat poultry farming and related industries have suffered significant economic losses.Although it is known that the development of TD is involved in such factors as growth velocity,breeding selection, diets blending and raising environmental factors.Although there were quite a lot researchs about the pathogenesis of TD, but the model is different, the TD associated pathogenesis is still unclear.Therefore, poultry TD relative mechanisms and prevention research has always been a matter of vital importance experts concerned.Some techniques, such as histopathology,Northern blot, in situ hybridization, immunohistochemistry, semi-quantitative RT-PCR or real-time PCR have been used to investigate the molecular mechanism of this disease. The results showed that expression of some genes were disordered, or its levels were lowered, or it was absent during the development of TD. In addition, the relevant enzymes, growth factors, etc,compared with normal growth plate has a different degree of change. Although the use of many methods to study TD related factor, because there is no suitable animal model, the lack of dynamic research, the pathogenesis of TD is still unclear.Although ten genes related to the development of broiler TD were selected by Tian Wenxia constructing cDNA library with suppression subtractive hybridization technology (SSH), these limited genes were not enough for revealing the etiology of TD. In the previous study, we found that development cycle of broiler tibial growth plate chondrocyte was short, it is likely that genes in the growth plates are differentially expressed at an early stage. In order to obtain differentially expressed genes(DEGs) in the early stage of TD, in this study, we induced TD using tetramethylthiuram disulfide (thiram), copy broiler TD pathological model, adjusting the sampling time, advance sample time and shorten the sampling time interval,use high-quality cDNA library clone point system chip,with different time points in control and test groups of growth plate cartilage cRNA probes hybridized to the chip, using cDNA microarray technology, high throughput screening of differentially expressed clone at different time points. Thereafter, differentially expressed clones were sequenced, homology, functional classification analysis. Gene differential expression at different stages in the development of TD was Validated by using real-time qPCR. The main results are as follows:1. For cDNA microarray analysis,we identified1398differentially expressed genes in six different stages, there differentially expressed genes exhibiting minimum2-fold or above changes,which corresponds to151,90,240,589,718and733differentially expressed genes exhibiting at d2,4,10,12,15and20, respectively.2. GeneOntology annotations for molecular function show changes in the expression of molecules involved in regulation, transition, transport, oxidation reduction or redox homeostasis, signal transduction, biosynthesis, metabolism, protein folding and proteolysis, immune response or defense response, response to stress, apoptosis or anti-apoptosis, RNA processing and modification, transcription or regulation of transcription, translational elongation, cell cycle, cell proliferation division, development, cell adhesion, electron transport chain and glycosylation process.3. We selected eleven genes, lysyl oxidase (LOX), heat shock protein25(Hsp25), inhibitor of DNA binding1(Id1), kinectin1(KTN1),.secreted frizzled-related protein4(Sfrp4), cadherin1(Cdhl) and enolase2(ENO2), collagen,typVI alpha2(Co16a2), glutathione S-transferase alpha3(Gstα3), cysteine-rich, angiogenic inducer61(Cyr61), intraflagellar transport88homolog (Ift88), to confirm the cDNA microarray data using real-time qPCR. The results indicated that the expression patterns of twelve genes are consistent with the cDNA microarray data.The study of these differentially expressed genes, can help us fully understand the pathogenesis of broiler TD and for the prevention and treatment of TD open new avenues.