Limits...
Horizontal gene transfer in silkworm, Bombyx mori.

Zhu B, Lou MM, Xie GL, Zhang GQ, Zhou XP, Li B, Jin GL - BMC Genomics (2011)

Bottom Line: The domesticated silkworm, Bombyx mori, is the model insect for the order Lepidoptera, has economically important values, and has gained some representative behavioral characteristics compared to its wild ancestor.Results from this study clearly demonstrated that HGTs play an important role in the evolution of B. mori although the number of HGT events in B. mori is in general smaller than those of microbes and other insects.In particular, interdomain HGTs in B. mori may give rise to functional, persistent, and possibly evolutionarily significant new genes.

View Article: PubMed Central - HTML - PubMed

Affiliation: State Key Laboratory of Rice Biology and Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Ministry of Agriculture, Institute of Biotechnology, Zhejiang University, Hangzhou 310029, China.

ABSTRACT

Background: The domesticated silkworm, Bombyx mori, is the model insect for the order Lepidoptera, has economically important values, and has gained some representative behavioral characteristics compared to its wild ancestor. The genome of B. mori has been fully sequenced while function analysis of BmChi-h and BmSuc1 genes revealed that horizontal gene transfer (HGT) maybe bestow a clear selective advantage to B. mori. However, the role of HGT in the evolutionary history of B. mori is largely unexplored. In this study, we compare the whole genome of B. mori with those of 382 prokaryotic and eukaryotic species to investigate the potential HGTs.

Results: Ten candidate HGT events were defined in B. mori by comprehensive sequence analysis using Maximum Likelihood and Bayesian method combining with EST checking. Phylogenetic analysis of the candidate HGT genes suggested that one HGT was plant-to- B. mori transfer while nine were bacteria-to- B. mori transfer. Furthermore, functional analysis based on expression, coexpression and related literature searching revealed that several HGT candidate genes have added important characters, such as resistance to pathogen, to B. mori.

Conclusions: Results from this study clearly demonstrated that HGTs play an important role in the evolution of B. mori although the number of HGT events in B. mori is in general smaller than those of microbes and other insects. In particular, interdomain HGTs in B. mori may give rise to functional, persistent, and possibly evolutionarily significant new genes.

Show MeSH
Flowchart of the methodology used to search for HGT genes in Bombyx mori and of the results of each step.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC3116507&req=5

Figure 1: Flowchart of the methodology used to search for HGT genes in Bombyx mori and of the results of each step.

Mentions: Each candidate sequence in B. mori was compared against sequences in the local database using BLASTp [14] and the highest similarity sequences from each species were extracted for further analysis (E-value cutoff 10-20). We used the local database first to exclude insect unique genes and the genes that, when compared against all the genomes showed a higher BLASTp similarity score to Arthropoda than to any other species (Figure 1). All sequences that had a high sequence similarity to the transposon were also excluded from further analysis as we aimed to study the effect of HGT on the putative functional genes (Figure 1). After detecting the putative transferred genes, expression sequence tags (EST) information was used to remove out the unexpressed genes. The detailed procedure was showed in Figure 1.


Horizontal gene transfer in silkworm, Bombyx mori.

Zhu B, Lou MM, Xie GL, Zhang GQ, Zhou XP, Li B, Jin GL - BMC Genomics (2011)

Flowchart of the methodology used to search for HGT genes in Bombyx mori and of the results of each step.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3116507&req=5

Figure 1: Flowchart of the methodology used to search for HGT genes in Bombyx mori and of the results of each step.
Mentions: Each candidate sequence in B. mori was compared against sequences in the local database using BLASTp [14] and the highest similarity sequences from each species were extracted for further analysis (E-value cutoff 10-20). We used the local database first to exclude insect unique genes and the genes that, when compared against all the genomes showed a higher BLASTp similarity score to Arthropoda than to any other species (Figure 1). All sequences that had a high sequence similarity to the transposon were also excluded from further analysis as we aimed to study the effect of HGT on the putative functional genes (Figure 1). After detecting the putative transferred genes, expression sequence tags (EST) information was used to remove out the unexpressed genes. The detailed procedure was showed in Figure 1.

Bottom Line: The domesticated silkworm, Bombyx mori, is the model insect for the order Lepidoptera, has economically important values, and has gained some representative behavioral characteristics compared to its wild ancestor.Results from this study clearly demonstrated that HGTs play an important role in the evolution of B. mori although the number of HGT events in B. mori is in general smaller than those of microbes and other insects.In particular, interdomain HGTs in B. mori may give rise to functional, persistent, and possibly evolutionarily significant new genes.

View Article: PubMed Central - HTML - PubMed

Affiliation: State Key Laboratory of Rice Biology and Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Ministry of Agriculture, Institute of Biotechnology, Zhejiang University, Hangzhou 310029, China.

ABSTRACT

Background: The domesticated silkworm, Bombyx mori, is the model insect for the order Lepidoptera, has economically important values, and has gained some representative behavioral characteristics compared to its wild ancestor. The genome of B. mori has been fully sequenced while function analysis of BmChi-h and BmSuc1 genes revealed that horizontal gene transfer (HGT) maybe bestow a clear selective advantage to B. mori. However, the role of HGT in the evolutionary history of B. mori is largely unexplored. In this study, we compare the whole genome of B. mori with those of 382 prokaryotic and eukaryotic species to investigate the potential HGTs.

Results: Ten candidate HGT events were defined in B. mori by comprehensive sequence analysis using Maximum Likelihood and Bayesian method combining with EST checking. Phylogenetic analysis of the candidate HGT genes suggested that one HGT was plant-to- B. mori transfer while nine were bacteria-to- B. mori transfer. Furthermore, functional analysis based on expression, coexpression and related literature searching revealed that several HGT candidate genes have added important characters, such as resistance to pathogen, to B. mori.

Conclusions: Results from this study clearly demonstrated that HGTs play an important role in the evolution of B. mori although the number of HGT events in B. mori is in general smaller than those of microbes and other insects. In particular, interdomain HGTs in B. mori may give rise to functional, persistent, and possibly evolutionarily significant new genes.

Show MeSH