The Complete Chloroplast Genome Sequence Of Morus Atropurpurea And Morus Multicaulis

The structure and composition of the chloroplast genome are more conservative and the variation rate of the fragment is moderate,which is suitable for the systematic evolution of the plant.The cultivated species of M.atropurpurea Roxb“Yichuanhong” and M.multicaulis Perr “Ribentiancheng” are used as experimental materials,Illumina high-throughput sequencing technology is used to sequence the chloroplast genome and the genome structure,and compared it with the genomes of reported sibling species(M.mongolica Schneid,M.indica Linne,Morus notabilis Schneid).The results are as follows:1.The chloroplast genome of M.atropurpurea Roxb is 159113 bp in size and comprises of two identical inverted repeat(IR)regions of 25707 bp each,which separated by a large single-copy(LSC)region of 87824 bp and a small single-copy(SSC)region of 19875 bp;The chloroplast genome of M.multicaulis Perr with a typical quadripartite structure is 159154 bp in length and contains a pair of inverted repeat regions of 25678 bp,a large single-copy region of 87763 bp and a small single-copy region of 20035 bp.2.The chloroplast genome(cp DNA)of M.atropurpurea Roxb and M.multicaulis Perr all contains 130 genes,including 85 protein coding genes(PCG)(18 genes duplicated in the inverted repeat regions),37 transfer RNA(t RNA)genes and 8 ribosomal RNA(r RNA)genes,twenty-four of them contain introns,22 genes have one intron and two genes(ycf3 and clpP)have two introns.3.The number of gene,classification and the content of CG are similar with other Morus L.plants.83 simple sequence repeats(SSR)loci getting by bioinformatics analysis are rich in A-T,which has obvious base's preferences,the number of mono-,di-,tri-,tetra-,pentanucleotide repeat motifs is 60,8,3,10,2,but no hexanucleotide repeat sequences;In addition,there are 82 simple sequence repeats containing 63 mononucleotide repeats in M.multicaulis Perr,the number of mono-,di-,tri-,tetra-,pentanucleotide repeat motifs is 63,7,2,9,1,and no hexanucleotide repeat sequences were found.Mono-nucleotide repeat sequences in the chloroplast genome of SSR accounted for 76.8%.All of the nucleotide and 14 SSR polynucleotide are be made up of A and T.To investigate the location of SSR,10 nucleotide repeat motifs in the coding region,and the rest in the non coding region.Most loci are biased towards A or T.4.Meanwhile,MEGA 6.0 was used to construct the phylogenetic tree of 27 species and clustered analysis Morus L.plants.The method showed that M.atropurpurea Roxb and M.mongolica Schneid gather into a group,M.indica Linne and M.notabilis Schneid gather into a another group.The research results have reference value for the research of chloroplast genome project,the development of molecular markers and the cultivation of fine varieties of mulberry.