Helliwell Chris A, Wood Craig C, Robertson Masumi, James Peacock W, Dennis Elizabeth S
CSIRO Plant Industry, GPO Box 1600, Canberra ACT 2601, Australia.
Plant J. 2006 Apr;46(2):183-92. doi: 10.1111/j.1365-313X.2006.02686.x.
The Arabidopsis Flowering Locus C (FLC) protein is a repressor of flowering regulated by genes in the autonomous and vernalization pathways. Previous genetic and transgenic data have suggested that FLC acts by repressing expression of the floral integrator genes SOC1 and FT. We have taken an in vivo approach to determine whether the FLC protein interacts directly with potential DNA targets. Using chromatin immunoprecipitation, we have shown that FLC binds to a region of the first intron of FT that contains a putative CArG box, and have confirmed that FLC binds to a CArG box in the promoter of the SOC1 gene. MADS box proteins are thought to bind their DNA targets as dimers or higher-order multimers. We have shown that FLC is a component of a multimeric protein complex in vivo and that more than one FLC polypeptides can be present in the complex.
拟南芥开花位点C（FLC）蛋白是自主途径和春化途径中受基因调控的开花抑制因子。先前的遗传和转基因数据表明，FLC通过抑制开花整合基因SOC1和FT的表达来发挥作用。我们采用体内实验方法来确定FLC蛋白是否直接与潜在的DNA靶点相互作用。通过染色质免疫沉淀，我们发现FLC结合到FT第一个内含子中一个包含假定CArG框的区域，并证实FLC结合到SOC1基因启动子中的一个CArG框。MADS盒蛋白被认为以二聚体或更高阶多聚体的形式结合其DNA靶点。我们已经证明，FLC在体内是多聚体蛋白复合物的一个组成部分，并且复合物中可以存在不止一个FLC多肽。
