Objective To study the sequence characteristics of Dendrobium officinale

Method Local BLASTP was used to search the phytocyanin gene of D. officinale(DoPCs) in the database of Dendrobium whole genome, and then the conserved Plastocyanin-like domain and structural characteristics of DoPCs were predicted. The sequence alignment and phylogenetic analysis of DoPCs were conducted by using Clustal W and MEGA. Finally, 38 DoPCs were expected to have conserved PCLD domains and two Cys residues, belonging to four subfamilies.

Result Among these DoPC proteins, 19 DoPCs contained four copper ligands (His, Cys, His, and Gln/Met), 32 DoPCs were predicted having N-terminal signal peptides, 22 DoPCs had putative C-terminal glycosylphosphatidylinositol-anchor signals, and 27 DoPCs had putative arabinogalactan glycomodules. The results of DoPCs expression analysis in symbiotic with Tulasnella calospora and asymbiotic germinated seeds from D. officinale by using RNA-seq data showed that 16 DoPCs were expressed in symbiotic germinated seeds, and DoUCL2, 4 and DoENODL14 had the highest expression with different levels. Seven DoPC genes were obviously up-regulated and only one was down-regulated in symbiotic germinated seeds comparing with that of asymbiotic.

Conclusion The study of the protein structure characteristics of DoPCs family in Dendrobium officinale during the whole genome, would help in researching the interaction between Orchidaceae and microorganism, furthermore would serve as data foundation, in researching the molecular mechanism of Orchid mycorrhiza growth.