Characterization and expression of the Hex 110 gene encoding a glutamine‐rich hexamerin in the honey bee, Apis mellifera

Abstract

An N-terminal amino acid sequence of a previously reported honey bee hexamerin, HEX 110 [Danty et al., Insect Biochem Mol Biol 28:387-397 (1998)], was used as reference to identify the predicted genomic sequence in a public GenBank database. In silico analysis revealed an ORF of 3,033 nucleotides that encompasses eight exons. The conceptual translation product is a glutamine-rich polypeptide with a predicted molecular mass of 112.2 kDa and pI of 6.43, which contains the conserved M and C hemocyanin domains. Semiquantitative and quantitative RT-PCR with specific primers allowed for an analysis of mRNA levels during worker bee development and under different physiological conditions. Concomitantly, the abundance of the respective polypeptide in the hemolymph was examined by SDS-PAGE. Hex 110 transcripts were found in high levels during the larval stages, then decreased gradually during the pupal stage, and increased again in adults. HEX 110 subunits were highly abundant in larval hemolymph, decreased at the spinning-stage, and remained at low levels in pupae and adults. In 5th instar larvae, neither starvation nor supplementation of larval food with royal jelly changed the Hex 110 transcript levels or the amounts of HEX 110 subunit in hemolymph. In adult workers, high levels of Hex 110 mRNA, but not of the respective subunit, were related to ovary activation, and also to the consumption of a pollen-rich diet.

Characterization of a novel member of genus Iflavirus in Helicoverpa armigera

“…And, some members of Iflavirus are known to be harmful to their hosts by lead to developmental problems and host mortality (van Oers, 2010). For example, sacbrood virus (SBV) is mainly found in larval fat body cells of the honeybee, which may impact metabolic function of these cells, resulting in failure to pupate and ultimately causing death (Bitondi et al, 2006;Park et al, 2016). Interestingly, HaIV was also mainly distributed in the fat body both in larvae and adults while with much lower titers in both the ovary and testis, suggesting a similar function with other members of genus Iflavirus.…”

Validation of reference genes for gene expression studies in the honey bee,Apis mellifera, by quantitative real-time RT-PCR

“…As far as we know, this is the first systematic study comparing different candidate reference genes for qRT-PCR in honey bees. In previous qRT-PCR studies on this species, reference genes have been selected based on consensus and experience in other organisms, such as ribosomal protein S5-rpS5 (Evans, 2004;Zou et al, 2006), ef1-alpha (Yamazaki et al, 2006), rp49 (Grozinger et al, 2003;Corona et al, 2007), and actin (Lourenço et al, 2005;Bitondi et al, 2006). In a systematic approach to find the best-suited reference genes for qRT-PCR in honey bees, we analyzed the behavior of four candidate reference genes (act, rp49, ef1-alpha and tbp-af) by statistical analyses of variation in different biological conditions and entered these data into three established software programs for reference gene selection, geNorm, BestKeeper and NormFinder.…”

Detailed proteome mapping of newly emerged honeybee worker hemolymph and comparison with the red-eye pupal stage

“…Hexamerins 70b and 70c exhibit a similar developmental profile because they disappear from the hemolymph with worker emergence, while hexamerin 110 disappears earlier than 70b and 70c (Danty et al 1998). Bitondi et al (2006) found that hexamerin 110 subunits are highly abundant in larval hemolymph, but are decreased at the larval spinning stage, and remain at low levels in pupae and adults (Bitondi et al 2006).…”