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

• Published in: Journal of insect physiology Vol. 54; no. 7; pp. 1138 - 1147
• Main Authors: Guidugli-Lazzarini, Karina Rosa, do Nascimento, Adriana Mendes, Tanaka, Érica Donato, Piulachs, Maria Dolors, Hartfelder, Klaus, Bitondi, Márcia Gentile, Simões, Zilá Luz Paulino
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01-07-2008
• Subjects: Amino Acid Sequence; Animals; Apis mellifera; Bees - chemistry; Bees - classification; Bees - genetics; Bees - metabolism; Egg Proteins - chemistry; Egg Proteins - genetics; Egg Proteins - metabolism; Female; gene expression; Gene Expression Regulation; Honeybee; Insect Proteins - chemistry; Insect Proteins - genetics; Insect Proteins - metabolism; LDLR; lipophorin; Lipophorin receptor; Male; messenger RNA; Molecular Sequence Data; ovarian development; Ovary; Phylogeny; Polymerase Chain Reaction; protein isoforms; Protein Structure, Tertiary; queen honey bees; receptors; 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; sequence analysis; Species Specificity; tissue distribution; vitellogenin; Vitellogenin receptor; vitellogenin receptors; worker honey bees; Ovary; Honeybee; Vitellogenin receptor; LDLR; Lipophorin receptor
• ISSN: 0022-1910; 1879-1611
• DOI: 10.1016/j.jinsphys.2008.04.021

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.