Expression pattern of CYC-like genes relating to a dorsalized actinomorphic flower in Tengia(Gesneriaceae)  

作　　者：Hong-Bo PANG Qing-Wen SUN Shun-Zhi HE Yin-Zheng WANG 

机构地区：[1]State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany Chinese Academy of Sciences, Beijing 100093, China [2]Guiyang College of Traditional Chinese Medicine, Guiyang 550002, China

出　　处：《Journal of Systematics and Evolution》2010年第5期309-317,共9页植物分类学报（英文版）

基　　金：supported by the Chinese Academy of Sciences (Grant No KSCX2-YW-R-135);the National Natural Science Foundation of China (Grant No 30770147)

摘　　要：Tengia has been called a ＂natural peloria＂ in the family Gesneriaceae because it exhibits an almost perfect actinomorphic flower from whorl one to whorl three. It would be especially interesting to know whether or how CYC-like gene activities are related to this type of perfect actinomorphic flower. To address this, we have isolated four CYC-like TCP genes and carried out an investigation on their expression patterns in Tengia. TsCYC1C and TsCYC1D have similar expression patterns with strong signals being detected in all five petals and stamens, whereas TsCYC2A and TsCYC2B are only transiently expressed in the very early floral meristem. Our results suggest that the expansion of the expressions of TsCYC1C and TsCYC1D from the dorsal to the ventral petals is likely responsible for the evolutionary formation of the fully dorsalized actinomorphic corolla, that is, an expanded functional domain of CYC-like gene dorsal identity in Tengia corolla. However, the expressions of TsCYC1C and TsCYC1D are not correlated with stamen abortion; therefore, TsCYC genes do not functionally repress the stamen development in Tengia flowers. This is probably due to changed cis-activities that result in the cell cycle-related genes uncoupling from the TsCYC regulatory pathway in Tengia.Tengia has been called a ＂natural peloria＂ in the family Gesneriaceae because it exhibits an almost perfect actinomorphic flower from whorl one to whorl three. It would be especially interesting to know whether or how CYC-like gene activities are related to this type of perfect actinomorphic flower. To address this, we have isolated four CYC-like TCP genes and carried out an investigation on their expression patterns in Tengia. TsCYC1C and TsCYC1D have similar expression patterns with strong signals being detected in all five petals and stamens, whereas TsCYC2A and TsCYC2B are only transiently expressed in the very early floral meristem. Our results suggest that the expansion of the expressions of TsCYC1C and TsCYC1D from the dorsal to the ventral petals is likely responsible for the evolutionary formation of the fully dorsalized actinomorphic corolla, that is, an expanded functional domain of CYC-like gene dorsal identity in Tengia corolla. However, the expressions of TsCYC1C and TsCYC1D are not correlated with stamen abortion; therefore, TsCYC genes do not functionally repress the stamen development in Tengia flowers. This is probably due to changed cis-activities that result in the cell cycle-related genes uncoupling from the TsCYC regulatory pathway in Tengia.

关 键 词：actinomorphy CYCLOIDEA dorsalized GESNERIACEAE RNA in situ hybridization Tengia. 

分 类 号：S512.103.4[农业科学—作物学] S511.03