Proteome Analysis of Male Accessory Gland Secretions in the Diamondback Moth, Plutella xylostella (Lepidoptera: Plutellidae)

Abstract

In insects, male accessory gland proteins (ACPs) are important reproductive proteins secreted by male accessory glands (MAGs) of the internal male reproductive system. During mating, ACPs are transferred along with sperms inside female bodies and have a significant impact on the post-mating physiology changes of the females. Under sexual selection pressures, the ACPs exhibit remarkably rapid and divergent evolution and vary from species to species. The diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), is a major insect pest of cruciferous vegetables worldwide. Mating has a profound impact on the females’ behavior and physiology in this species. It is still unclear what the ACPs are in this species. In this study, two different proteomic methods were used to identify ACPs in P. xylostella. The proteins of MAGs were compared immediately before and after mating by using a tandem mass tags (TMT) quantitative proteomic analysis. The proteomes of copulatory bursas (CB) in mated females shortly after mating were also analyzed by the shotgun LC-MS/MS technique. In total, we identified 123 putative secreted ACPs. Comparing P. xylostella with other four insect ACPs, trypsins were the only ACPs detected in all insect species. We also identified some new insect ACPs, including proteins with chitin binding Peritrophin-A domain, PMP-22/ EMP/ MP20/ Claudin tight junction domain-containing protein, netrin-1, type II inositol 1,4,5-trisphosphate 5-phosphatase, two spaetzles, allatostatin-CC, and cuticular protein. This is the first time that ACPs have been identified and analyzed in P. xylostella. Our results have provided an important list of putative secreted ACPs, and have set the stage for further exploration of the functions of these putative proteins in P. xylostella reproduction.

An Orphan Gene Enhances Male Reproductive Success in Plutella xylostella

“…To confirm this hypothesis, we separated the female and male adults 30 min after mating. Previous studies showed that 30 min was adequate for sperm transfer from males to females in P. xylostella ( Wu et al 2023 ). The number of eggs laid were then recorded.…”

“…It was found that the abundance of Lushu does not exhibit a significant decrease in the male accessory gland (MAG) after mating (NSAF = 0.00263 before mating vs. NSAF = 0.00256 after mating, Student's t -test, P = 0.11), although it showed high abundance in female bursa ( Table 1 ). Secondly, a previous study of P. xylostella identified seminal fluid proteins (SFPs) based on proteome analysis, but Lushu was not among these proteins identified ( Wu et al 2023 ). Thirdly, sperm samples used in immunofluorescence assays were collected from testes ( Fig.…”

SPSL1 is essential for spermatophore formation and sperm activation in Spodoptera frugiperda

“…Trypsin-type serine proteases are known as components transferred from males to females and are crucial for fertility in diverse species [ 24 – 26 , 38 ]. Despite our previous work found that the mutation of Ser1 causes male sterility in B .…”

“…SFPs in lepidopteran insects, including Bombyx mori , Spodoptera litura , Plutella xylostella , have been found to contain numerous trypsin-type serine proteases and play important roles in male reproduction [ 24 – 26 ]. In B .…”

“…SFPs in lepidopteran insects, including Bombyx mori, Spodoptera litura, Plutella xylostella, have been found to contain numerous trypsin-type serine proteases and play important roles in male reproduction [24][25][26]. In B. mori, a trypsin-type protease called Initiatorin, also known as Serine Protease 2 (Ser2), has been identified as a sperm activation factor through in vitro enzyme treatment experiments [27].…”