Abstract: ObjectiveBioinformatics tools were used to analyze the structure and function of gene MS1 in Brassica, and provide reference for utilization of crop heterosis.MethodSequence of Arabidopsis thaliana L.pollen development gene AtMS1 was used as reference sequence.BLAST alignment was adopted to obtain homologous gene sequence,and bioinformatic method was carried out to predict the sequence of encoded amino acids.ResultFour homologous sequen-ces were obtained from genome of B.napus L.,B.rapa L.and B.oleracea L.,whose similarities with gene AtMS1 were more than 88.0%.They all contained three exons,encoded 667 amino acids with CDS sequence length as 2004 bp.The four MS1 proteins of Brassica crops all contained one plant homeodomain(PHD),belonging to hydrophilic unstable pro-teins.They all located in nucleus,with serine(Ser)was the main phosphorylation and threonine(Thr)and tyrosine(Tyr) as auxiliary phosphorylation.The secondary structure was made up by α-helix,β-turn,extended strand and random coil. The proportion of α-helix was the highest(over 40.00%),and that of β-turn the lowest(10.00%).Their tertiary structures were similar,which were spherical function domain.The similarity of sequence between MS1 proteins of four Brassica crops and A.thaliana protein AtMS1was 95.69%.PHD structure sequences of MS1 proteins from the four Brassica crops were highly conservative.Differences were only existed in amino acid residue of three sites.MS1 homologous proteins of 19 different crops clustered into two types.MS1 proteins of A.lyrata,Camelina sativa and Raphanus sativus L.clustered into one type with MS1 proteins of four Brassica crops and protein AtMS1 of A.thaliana,which all belonged to Crucife-rae.The results indicated that the cluster of MS1 proteins was in line with plant systematics.ConclusionGene MS1 of Brassica crops belong to PHD-finger gene family.Their sequences are highly conservative,and play a role in regulating pollen development and maturity.