Why is ethylene involved in selective promotion of female flower development in cucumber?
Our recent work by Wang et al (2010), together with previous studies published in the last decade, have provided evidence suggesting a link between ethylene signaling and primordial anther specific DNA damage in female cucumber flowers. These findings explained ethylene promotion of female flower by ethylene inhibition of stamen development. However, it is not determined if ethylene promotes carpel development. In addition, an explanation of why the naturally occurring gas ethylene was selected to be involved in such developmental events remains elusive. In this study, we carried out a phylogenetic analysis of cucumber ACS genes, and analyzed the expression levels of some pre-miRNAs in male, female and hermaphrodite flowers. We found the M gene might have evolved prior to, or "co-opted" into unisexual flower development before the F gene, and miRNA might be involved in carpel development regulation. Based on these observations, we propose a new hypothesis to explain why ethylene was selected to be involved in the evolution of the unisexual cucumber flower.
Sun
Jin-Jing
JJ
PKU-Yale Joint Research Center of Agricultural and Plant Molecular Biology, National Key Laboratory of Protein Engineering and Plant Gene Engineering, College of Life Sciences, Peking University, Beijing, China.
Li
Feng
F
Li
Xia
X
Liu
Xiao-Chuan
XC
Rao
Guang-Yuan
GY
Luo
Jing-Chu
JC
Wang
Dong-Hui
DH
Xu
Zhi-Hong
ZH
Bai
Shu-Nong
SN
D018553:Cucumis sativus / Q000235:genetics / Q000254:growth & development*; D004249:DNA Damage; D005030:Ethylenes / Q000378:metabolism*; D035264:Flowers / Q000235:genetics / Q000254:growth & development*; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D035683:MicroRNAs / Q000235:genetics*; D010802:Phylogeny; D018749:RNA, Plant / Q000235:genetics
D005030:Ethylenes; D035683:MicroRNAs; D018749:RNA, Plant; C036216:ethylene