title: A genomewide survey of homeobox genes and identification of novel structure of the Hox cluster in the silkworm, Bombyx mori.
abstract: Homeobox genes encode transcriptional factors that play crucial roles in a variety of developmental pathways from unicellular to multicellular eukaryotes. We have identified 102 homeobox genes in the typical insect of Lepidoptera, Bombyx mori, based on the newly assembled genome sequence with 9X coverage. These identified homeobox genes were categorized into nine classes including at least 74 families. The available ESTs and microarray data at present confirmed that more than half of them were expressed during silkworm developmental processes. Orthologs of pb, zen and ftz were newly identified in the Bombyx Hox cluster on chromosome 6. Interestingly, a special group of 12 tandemly duplicated homeobox genes was found located between Bmpb and Bmzen in the Bombyx Hox cluster, suggesting that Hox cluster might have experienced a lineage-specific expansion in the silkworm. A detailed analysis on genome data reveals that a split exists between Bmlab and Bmpb. Our data provide valuable information for future research on the development and evolution of silkworm.
authors.affiliation: The Key Sericultural Laboratory of Agricultural Ministry, College of Biotechnology, Institute of Sericulture and Systems Biology, Southwest University, Chongqing, China
authors.forename: Chun-Li
authors.initials: CL
authors.lastname: Chai
authors.forename: Ze
authors.initials: Z
authors.lastname: Zhang
authors.forename: Fei-Fei
authors.initials: FF
authors.lastname: Huang
authors.forename: Xian-Yan
authors.initials: XY
authors.lastname: Wang
authors.forename: Quan-You
authors.initials: QY
authors.lastname: Yu
authors.forename: Bin-Bin
authors.initials: BB
authors.lastname: Liu
authors.forename: Tian
authors.initials: T
authors.lastname: Tian
authors.forename: Qing-You
authors.initials: QY
authors.lastname: Xia
authors.forename: Cheng
authors.initials: C
authors.lastname: Lu
authors.forename: Zhong-Huai
authors.initials: ZH
authors.lastname: Xiang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D012831:Bombyx / Q000235:genetics*; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation / Q000502:physiology; D005801:Genes, Homeobox; D017344:Genes, Insect; D049750:Genome, Insect; D019476:Insect Proteins / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D005810:Multigene Family; D010802:Phylogeny
chemical_list: D019476:Insect Proteins