Identification of major royal jelly proteins in the brain of the honeybee Apis mellifera

Abstract

The consumption of royal jelly (RJ) determines the differences between castes and behavioral development in the honeybee Apis mellifera. However, it is not known whether the proteins of RJ are related to these differences, or which proteins are responsible for the changes. To understand the functions of RJ proteins that are present in other tissues of the bee, in addition to hypopharyngeal gland, we used a polyclonal antibody anti-MRJP1 to investigate the presence of this protein in nervous system of honeybee. This study showed the presence of three polypeptides (p57, p70 and p128) in specific tissues of bee brain. Mushroom body, optic lobe and antennal lobe neuropils all contained proteins recognized by anti-MRJP1. Proteomic analysis showed that the three polypeptides are correlated with proteins of the MRJP family. p57 is correlated with MRJP1, p70 with MRJP3, while p128 may be an oligomeric form or a new polypeptide. Immunostaining of the brain and hypopharyngeal gland revealed differential expression of MRJPs in various brain regions and in different honeybee castes and subcastes. The identification and localization of these MRJPs contribute to the elucidation of the biological roles of this protein family.

Determination of royal jelly freshness by ELISA with a highly specific anti-apalbumin 1, major royal jelly protein 1 antibody

“…In this investigation, the anti-MRJP1 antibody was generated with natural MRJPs as antigen, then separated by SDS-PAGE, and excised and electrotransferred on to an NC. Bioinformatics analyses on the analogous antigenic regions among MRJPs showed that MRJP1, MRJP2, and MRJP3 have more than 44% identity, and MRJP1-5 proteins share seven antigenic conserved regions corresponding to the epitopes for the anti-MRJP1 antibody (Peixoto et al, 2009). The identities among MRJP sequences were suggested by hybridization assay and sequence alignment (Schmitzová et al, 1998;Albert et al, 1999;Drapeau et al, 2006;Peixoto et al, 2009).…”

“…This antibody recognizes MRJP family members in the denatured protein. In addition, sequence analysis of all of the MRJP family members contains an N-terminal hydrophobic sequence that would function as a cleavable signal peptide as well as a putative N-linked glycosylation site (Drapeau et al, 2006;Peixoto et al, 2009;Klaudiny et al, 2010). Yamaguchi et al (2013) were the first to determine MRJP1 levels in RJ samples from different companies with specific MRJP1 antibody.…”

“…MRJP1, in the form of an oligomeric complex, has more biological functions than its nutritional role in the larval development of honeybees. It is expressed in the brain mushroom bodies and nervous system of the adult (Peixoto et al, 2009). Previously designated as royalactin, it was recently found to induce the differentiation of honeybee larvae into queens through an epidermal growth factor receptor (EGFR)-mediated signaling pathway.…”

Calcium effect and pH-dependence on self-association and structural stability of the Apis mellifera major royal jelly protein 1

“…MRJPs are similar to yellow proteins from Drosophila melanogaster and other insects as well as to putative proteins from bacteria (Albert and Klaudiny 2004;Drapeau et al 2006). Little is known about biological functions of such a class of proteins, but some suggestions have been proposed like sex-specific reproductive maturation (Drapeau et al 2006) and developmental processes in bee nervous system (Peixoto et al 2009). They are linked to queen development by still unclear mechanisms (Albert and Klaudiny 2004;Consortium, 2006).…”

Diet and endocrine effects on behavioral maturation-related gene expression in the pars intercerebralis of the honey bee brain

“…A total of four 'HPG genes' were filtered from nurse-forager gene list (FDR<0.1), 22 'HPG genes' were filtered from JHA (FDR<0.1), whilst none was filtered from the diet gene list (FDR<0.1). Expression of a few major royal jelly protein genes have been found in the mushroom bodies of the bee brain (Peixoto et al, 2009), so it is possible that some of these genes were expressed in the brain, but without further validation we cannot determine if these genes were expressed in the PI or the HPG. Because the number of genes is relatively small compared with the 13,774 total analyzed here, we chose this conservative approach.…”