Phylogeny Of The EIN3/EIL Genes Family

Ethylene is a kind of gaseous plant hormone and regulates the growth and development of plants,including seed germination,root formation and differentiation,flowering,pistillate floral development,leaf senescence and fall,fruit maturity,and so on.The EIN3/EIL gene family numbers are key genes in ethylene signal transduction pathway.In this study,we identified all the EIN3/EIL genes from each genome of 37 different species through bioinformatic methods.According to the phylogenetic and bioinformatic analysises,e.g.the structure of the exons and introns,the analysis of conserved motifs,whole genome duplication and expression profile,we revealed the potential function of female flower differentiation and flower development for the EIN3/EIL genes.The main results were as follows.1.We selected 37 species that have been sequenced of the genome for identifying EIN3/EIL family genes,including 5 monocots,24 dicotyledonous plants,1 fern,1 gymnosperm,1 moss,5 algaes.As a result,a total of 203 EIN3/EIL family genes were identified.However,no EIN3/EIL family gene was identified in algae species.And we identified 6,9,7,8,and 9 E1N3/EIL genes from the genomes of short stalk grass,rice,sorghum,millet and maize,respectively.2.The plant EIN3/EIL proteins were evolutionally divergent and diversified.The EIN3/EIL proteins in Poaceae were divided into 4 subfamilies.The analysis of intron-exon structure showed that most EIN3/EIL genes have no intron except that one gene in rice possesses only one introns.3.Gene duplication plays crutial roles in the expansion and evolution of EIN3/EIL gene family in Poaceaeand in dicotyledonous plants,such as poplar and cassava.Colinearity analysis between Poaceae plants indicated that several paired homologs of EIN3/EIL genes were located in syntenic genomic regions,suggesting that these syntenic orthologs likely share a common ancestor and similar biological functions.And they also have several paired homologs of EIN3/EIL genes between Poaceae and Amborella,between poplar and cassava.The EIN3/EIL genes may help to promote the development of pistil or female flowers in poplar,papaya,cassava,castor and flax.4.The EIN3/EIL genes transcribed relatively high in flower,leaf,root and stem in rice.The transcriptional levels of Os24109079.Os24126076 and Os24128240 gene were much higher than other genes in rice.Os24126076 and Os24128240 genes play an important role in regulating floral development.In sorghum,Sb1953535 gene played an important role in the development of flower,root and seedling.In Amborella,Am31559491 gene could promote the development of female flower buds.