title: Identification and analysis of YELLOW protein family genes in the silkworm, Bombyx mori.
abstract: BACKGROUND
  The major royal jelly proteins/yellow (MRJP/YELLOW) family possesses several physiological and chemical functions in the development of Apis mellifera and Drosophila melanogaster. Each protein of the family has a conserved domain named MRJP. However, there is no report of MRJP/YELLOW family proteins in the Lepidoptera.
  
  
  RESULTS
  Using the YELLOW protein sequence in Drosophila melanogaster to BLAST silkworm EST database, we found a gene family composed of seven members with a conserved MRJP domain each and named it YELLOW protein family of Bombyx mori. We completed the cDNA sequences with RACE method. The protein of each member possesses a MRJP domain and a putative cleavable signal peptide consisting of a hydrophobic sequence. In view of genetic evolution, the whole Bm YELLOW protein family composes a monophyletic group, which is distinctly separate from Drosophila melanogaster and Apis mellifera. We then showed the tissue expression profiles of Bm YELLOW protein family genes by RT-PCR.
  
  
  CONCLUSIONS
  A Bombyx mori YELLOW protein family is found to be composed of at least seven members. The low homogeneity and unique pattern of gene expression by each member among the family ensure us to prophesy that the members of Bm YELLOW protein family would play some important physiological functions in silkworm development.
authors.affiliation: The Sericultural Research Institute, Chinese Academy of Agricultural Sciences, Zhenjiang City, Jiangsu Province, 212018, China. tinyhuahua@163.com
authors.forename: Ai-Hua
authors.initials: AH
authors.lastname: Xia
authors.forename: Qing-Xiang
authors.initials: QX
authors.lastname: Zhou
authors.forename: Lin-Lin
authors.initials: LL
authors.lastname: Yu
authors.forename: Wei-Guo
authors.initials: WG
authors.lastname: Li
authors.forename: Yong-Zhu
authors.initials: YZ
authors.lastname: Yi
authors.forename: Yao-Zhou
authors.initials: YZ
authors.lastname: Zhang
authors.forename: Zhi-Fang
authors.initials: ZF
authors.lastname: Zhang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D012831:Bombyx / Q000235:genetics*; D029721:Drosophila Proteins / Q000235:genetics; D020224:Expressed Sequence Tags; D015723:Gene Library; D006023:Glycoproteins / Q000235:genetics; D019476:Insect Proteins / Q000235:genetics* / Q000302:isolation & purification; D008969:Molecular Sequence Data; D005810:Multigene Family; D021141:Nucleic Acid Amplification Techniques / Q000379:methods; D010802:Phylogeny; D016601:RNA-Binding Proteins; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D014018:Tissue Distribution
chemical_list: D029721:Drosophila Proteins; D006023:Glycoproteins; D019476:Insect Proteins; C109593:MRJP3 protein, Apis mellifera; D016601:RNA-Binding Proteins; C050680:y protein, Drosophila