Cloning And Expression Analysis Of CmEMF Genes Of Flowering Inhibit Genes In Chrysanthemum

Chrysanthemum is China’s traditional flower, also is the one of the fourth cut flowers,many varities of chrysanthemum, for example like “Jinba”, is sensitive to photoperiod, andblooms in short-day conditions after enough vegetative development. But the regulation oflighting in factory production wastes lots of resource. So it’s significant to study thechrysanthemums that not sensitive to photoperiod. While the molecular breeding supplied aconveience way to resolve this problem.In this study, three EMF genes: CmEMF1, CmEMF2₁and CmEMF2₂were clonedand characterized from chrysanthemum, and their cDNA full-length are3648bp，2277bp and2109bp，and their proteins contain1044，627，609amio acids.The structures of the three deduced EMF proteins show CmEMF1protein has no specialfunction domain, while CmEMF2₁and CmEMF2₂both contain a C2H2zinc finger modifyand VEFS-box domains. CmEMF2proteins through the VEFS-box and C2H2zinc fingermodify domains associate with the HOX gene function in heterochromatin-mediatedrepression. And VEFS-box domains associated with other genes to mediate their expression.CmEMF2₁and CmEMF2₂proteins share a similarity of65.5％, and there are muchdifference of their constructures. CmEMF1protein has closer relationship with Medicagotruncatual and Rosa lucicae, CmEMF2share a closer relationship with Camellia sinensis andRicinus communis.The real-time RT-PCR showed that the two CmEMF2genes have different expressionpatterns. While, CmEMF1and CmEMF2₂shared a similar expression pattern, it indicatedthat they have similar function in mediating the chrysanthemum development, especially theirhigh expression in the later period of floweral buds differentiation, maybe associate togetherto repress the excessive expression of flower identity genes, like the AG gene. Their activitieswere all involved in both vegetative and reproductive development, and were required fornormal leaves growth and fine-tuning the expression of flower homeotic genes, to ensure thenormal development of chrysanthemum.