Expression analysis of putative vitellogenin and lipophorin receptors in honey bee (Apis mellifera L.) queens and workers

J Insect Physiol. 2008 Jul;54(7):1138-47. doi: 10.1016/j.jinsphys.2008.04.021. Epub 2008 Jun 19.

Abstract

Two members of the low density lipoprotein receptor (LDLR) family were identified as putative orthologs for a vitellogenin receptor (Amvgr) and a lipophorin receptor (Amlpr) in the Apis mellifera genome. Both receptor sequences have the structural motifs characteristic of LDLR family members and show a high degree of similarity with sequences of other insects. RT-PCR analysis of Amvgr and Amlpr expression detected the presence of both transcripts in different tissues of adult female (ovary, fat body, midgut, head and specifically hypopharyngeal gland), as well as in embryos. In the head RNA samples we found two variant forms of AmLpR: a full length one and a shorter one lacking 29 amino acids in the O-linked sugar domain. In ovaries the expression levels of the two honey bee LDLR members showed opposing trends: whereas Amvgr expression was upregulated as the ovaries became activated, Amlpr transcript levels gradually declined. In situ hybridization analysis performed on ovaries detected Amvgr mRNA exclusively in germ line cells and corroborated the qPCR results showing an increase in Amvgr gene expression concomitant with follicle growth.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Bees / chemistry
  • Bees / classification
  • Bees / genetics*
  • Bees / metabolism
  • Egg Proteins / chemistry
  • Egg Proteins / genetics*
  • Egg Proteins / metabolism
  • Female
  • Gene Expression Regulation*
  • Insect Proteins / chemistry
  • Insect Proteins / genetics*
  • Insect Proteins / metabolism
  • Male
  • Molecular Sequence Data
  • Phylogeny
  • Polymerase Chain Reaction
  • Protein Structure, Tertiary
  • Receptors, Cell Surface / chemistry
  • Receptors, Cell Surface / genetics*
  • Receptors, Cell Surface / metabolism
  • Receptors, Cytoplasmic and Nuclear / chemistry
  • Receptors, Cytoplasmic and Nuclear / genetics*
  • Receptors, Cytoplasmic and Nuclear / metabolism
  • Species Specificity

Substances

  • Egg Proteins
  • Insect Proteins
  • Receptors, Cell Surface
  • Receptors, Cytoplasmic and Nuclear
  • lipophorin receptor
  • vitellogenin receptor