提高蛋壳质量是家禽育种的一个主要育种目标。蛋壳基质蛋白质对蛋壳质量有重要影响。OC-17蛋白质是第一个被分离、也是唯一晶体结构被解析的蛋壳特异基质蛋白质。由于高度富含GC，在鸡参考基因组中没有被组装成功，也不能开展OC-17蛋白质对碳酸钙结晶作用机理以及表达调控网络研究。本研究在我们已获得cDNA全长序列基础上，利用钓BAC文库、DNA-FISH等技术手段来阐明OC-17基因结构、定位基因到鸡染色体。通过基因过表达、表达抑制试验以及不同发育与产蛋阶段的子宫部组织表达谱变化规律，构建OC-17表达调控网络。对预测的6个钙离子结合位点以及两个结构域进行定点突变，在293T细胞中表达重组蛋白。在体外钙化模型中研究突变重组蛋白质对碳酸钙沉积速度与晶体形成的影响，确认结合钙离子的氨基酸位点或者结构域。研究成果将有助于阐明蛋壳形成机制与生物钙化机制，对蛋品质改良也将有重要应用价值。

Eggshell quality improvement is one of the major breeding aims in poultry breeding. Eggshell matrix protein mainly affect eggshell quality via controlling and regulating the deposition of calcium carbonate in the calcified eggshell layer. Ovocleidin-17(OC-17) was the first eggshell-specific matrix protein to be isolated and characterized following its chromatographic purification after eggshell decalcification. OC-17 was also the first protein directly involved in the non-pathological biomineralization process resolved by x-ray diffraction. Genomic sequences of OC-17 were still unknown up to now because of the very high GC content. This study would utilize BAC fishing, long range PCR and other technologies to elucidate gene structure of OC-17. DNA FISH technology would be used to map OC-17 on chicken chromosome. Gene expression changes would be monitored in the cell lines via gene overexpression, inhibition of OC-17 in the chicken uterus tubular cell lines and transcriptomes in the different development stages and laying stages in the uterus. We would construct gene co-expression network based on the gene expression profiles. There are 6 amino acids and 2 structure domains which were predicted to interact specifically with calcium ions. We would introduce point mutation for these sites separately and express recombinant OC-17 proteins in 293T cell lines. The purified recombinant proteins would be used to study potential effects of candidate amino acids on the calcium carbonate deposition and crystal growth in vitro. Results of this study would be important for explaining mechanism of OC-17 on the calcium carbonate deposition and also would be helpful for eggshell quality improvement.