Identification and Analysis of Phosphatidyl Ethanolamine Binding Protein (PEBP) Family Gene in Alfalfa

Background: Phosphatidyl ethanolamine binding protein (PEBP) plays an important role in the formation of flowers. To identify the PEBP gene family of alfalfa in blossom, the PEBP gene family was selected from the transcriptome database of alfalfa with bioinformatics analysis, for their protein properties, functional domains, evolutionary relationships and expression patterns. Methods: A BLASTP search using Arabidopsis PEBP sequences as a query was performed against alfalfa proteome with a minimum identity of 75% and E-value of 1E-5. BLASTP search resulted in 17 protein candidates. Finally, we obtained a consensus list of ten proteins from the HMMER and BLASTP search. Redundant sequences were removed using CD-HIT which resulted in a total of nine PEBP candidates in alfalfa. Result: The results showed that there was a total of nine PEBP candidates in alfalfa, which could be divided into three sub-gene families, such as TFL1-like, MFT-like and FT-like groups. Chromosomal location analyses showed that nine PEBP members are distributed on five of the eight alfalfa chromosomes with chromosome 7 having the largest number of PEBP members (four members) while only three alfalfa PEBP proteins were annotated as MsFTa1, MsFTa2 and MsFTc. In addition, the motifs of this gene family were conservative with few differences in the number and types of conservative motifs. MsFTa1 and MsFTa2 are two strong candidates for florigen in alfalfa, while MsG0480024000.01 is a candidate which functions as a floral repressory.