The seminal fluid proteome of the honeybee Apis mellifera

authored by
Boris Baer, Joshua L. Heazlewood, Nicolas L. Taylor, Holger Eubel, A. Harvey Millar
Abstract

Ejaculates contain sperm but also seminal fluid, which is increasingly recognized to be of central importance for reproductive success. However, a detailed biochemical composition and physiological understanding of seminal fluid is still elusive. We have used MS to identify the 57 most abundant proteins within the ejaculated seminal fluid of the honeybee Apis mellifera. Their amino acid sequences revealed the presence of diverse functional categories of enzymes, regulators and structural proteins. A number have known or predicted roles in maintaining sperm viability, protecting sperm from microbial infections or interacting with the physiology of the female. A range of putative glycoproteins or glycosylation enzymes were detected among the 57, subsequent fluorescent staining of glycolysation revealed several prominant glycoproteins in seminal fluid, while no glycoproteins were detected in sperm samples. Many of the abundant proteins that accumulate in the seminal fluid did not contain predictable tags for secretion for the cell. Comparison of the honeybee seminal fluid proteins with Drosophila seminal fluid proteins (including secreted accessory gland proteins known as ACPs), and with the human seminal fluid proteome revealed the bee protein set contains a range of newly identified seminal fluid proteins and we noted more similarity of the bee protein set with the current human seminal fluid protein set than with the known Drosophila seminal fluid proteins. The honeybee seminal fluid proteome thus represents an important addition to available data for comparative studies of seminal fluid proteomes in insects.

External Organisation(s)
University of Western Australia
Type
Article
Journal
PROTEOMICS
Volume
9
Pages
2085-2097
No. of pages
13
ISSN
1615-9853
Publication date
04.2009
Publication status
Published
Peer reviewed
Yes
ASJC Scopus subject areas
Biochemistry, Molecular Biology
Electronic version(s)
https://doi.org/10.1002/pmic.200800708 (Access: Unknown)