Evolution Of Methyltransf_FA Domain-Containing Gene Family And Function Analysis Of FAMeT-Like Genes In Bombyx Mori

Bombyx mori,a kind of silk spinning insect,is the classic model organism in the biology filed,which has a very high economic value.Juvenile hormone synthesized from the pharynx body is a class of semi terpenoid derivatives,which widely exists in insects,crustaceans and some plants,and plays an important role in physiological and biochemical processes such as growth,development,metamorphosis and reproduction.Farnesoid methyl(MF)as a non ring oxidized form of juvenile hormone III(JHIII),is involved in the various physiological role of crustaceans.Famesoic acid 0-methyltransferase(FAMeT)catalyes Famesoic acid(FA)into Farnesoid methyl(MF),which is the rate limiting step step and terminal in the biosynthesis process of crustacea JH.The Methyltransf_FA domain with a length of about 110 amino acids is found in FAMeT of Crustacea.It is reported that there are Methyltransf_FA containing domains in the insect,and the CPAMD8 of human hormone binding proteins also contains Methyltransf_FA domain structure.At present,there are great differences in the reports about Methyltransf_FA function.The purpose of this study is to explore the evolution and origin of the Methyltransf_FA domain-containing gene family by taking the Methyltransf_FA domain as a breakthrough point.In addition,I also identified the FAMeT-like gene in the silkworm genome and made an evolutionary and functional exploration of it.The main conclusions obtained are as follows:The first part is about the evolution of proteins containing the Methyltransf_FA domain.We identified 160 members of the gene family with the Methyltransf_FA domain.The results showed that the Methyltransf_FA domain-containing gene is widespread in the whole biological world.From the most primitive bacteria to the higher vertebrates,there are traces of Methyltransf_FA domain.The Methyltransf_FA domain-containing genes of the species can be divided into nine subfamilies.The bacteria are located at the root of phylogenetic tree,indicating that the gene family probably originated from bacteria.The structure of Methyltransf_FA domain-containing protein is diversified and the Methyltransf_FA domain-containing gene replicates in a few specific species.The detection of positive selective pressure shows that the Methyltransf_FA domain-containing is more conservative and has experienced a strong purifying selection effect.We also identified 9 conserved motif in the Methyltransf_FA domain.It is speculated that these motifs may play an important role in the functional differentiation of the domain.For the first time,we propose a domain fusion model to predict the occurrence of Methyltransf_FA domain proteins.The second part explores the function of FAMeT-like gene in silkworm,Bombyx mori.Since the FAMeT genes in the identified insects contained the Methyltransf_FA domain and the DUF3421 domain,in order to investigate the functions of the Methyltransf_FA domain and the DUF3421 domain protein,I systematically identified 11 Methyltransf_FA domain-containing or DUF3421 domain-containing genes in silkworm,Bombyx mori.And it is called the FAMeT-like gene.The phylogenetic analysis of the insect FAMeT-like gene showed that the insect FAMeT-like can be divided into three branches.At the same time,we observe that specific gene replication occurs in many species in the same branch.Gene structure analysis showed that the structure of the genes is quite different.We identified a 27-amino acid conserved motif.Analysis of tissue-specific expression patterns showed that the expression of FAMeT-like genes in silkworms of Bombyx mori was quite different,and the expression levels of BGIBMGA002605 and BGIBMGA006306 genes were low in each tissue,while the expression levels of BGIBMGA002604 and BGIBMGA006344 were significantly higher in each tissue.In addition,the BGIBMGA006513 gene was expressed in a low amount in the malpighian tube and the BGIBMGA014005 gene was expressed in the ovary,head and blood cells,especially in blood cells.BGIBMGA002314,BGIBMGA006513,and BGIBMGA006318 are only highly expressed in the midgut,suggesting that they play a role in food digestion and nutrient absorption in the midgut.In addition to the high expression of BGIBMGA006319 gene in the midgut,the expression levels were high in the anterior,middle,posterior silk glands and malpighian tubes,presumably related to excretion and silk formation.In addition,comparisons of expression in the corpora allata and other tissues show FAMeT-like gene plays little,if any,role in JH related pathway.