Transcriptomic comparison of the royal jelly proteins coded in the hypopharyngeal glands of Apis mellifera and Geotrigona acapulconis

Abstract

Abstract Apis mellifera and Geotrigona acapulconis are two members of Apidae family with large morphological differences; that is G. acapulconis is stingless, smaller in size, lack of yellow pigmentation, different nest building and hive structure, among other differences. We also suggest that there are biochemical differences between A. mellifera and G. acapulconis related to the composition of their Royal Jelly proteins (RJPs) and Yellow family proteins (YFPs). For instances, it has been reported that RJPs are involved in larval development of A. mellifera, and the YFPs play an important role in pigmentation in these arthropods. In this work, the protein composition of RJPs and YFPs were investigated indirectly by performing transcriptome analysis of the hypopharyngeal glands (HG), which are the RJP and YFPs producers. The results showed the presence of transcripts coding for RJPs in both bees. These proteins belonging to the Major Royal Jelly proteins (MRJPs) only recorded in A. mellifera and YFPs, which were identified here in both bees, but in different proportions. Additionally, MRJPs were only found in A. mellifera. Yet, coding sequences of these type proteins were found as Royal Jelly protein-like (RJPL) in G. acalpuconis, which are evolved from the MRJP. Furthermore, the differences found between yellow proteins (YPs) could be directly associated to the color of such bees, and the lack of MRJPs in G. acapulconis, that are important for larval nutrition and development, could be a consequence of a poor development of the larvae. On the other hand, some of the differences could be the result of their different behavior. Some MRJPs are required for defense of the larvae against pathogens, which are related to the differences in their biological cycle. Unfortunately, other functions of RJPs are not yet fully characterized; so, it is imperative to continue the research of the functions of RJPs in bees for a better understanding of their biological role.