Evolutionary Proteomics Reveals Distinct Patterns of Complexity and Divergence between Lepidopteran Sperm Morphs

View/ Open
Issue Date
2019-04-20Author
Whittington, Emma
Karr, Timothy L.
Mongue, Andrew J.
Dorus, Steve
Walters, James R.
Publisher
Oxford University Press (OUP)
Type
Article
Article Version
Scholarly/refereed, publisher version
Rights
Copyright The Author(s) 2019. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution..
Metadata
Show full item recordAbstract
Spermatozoa are one of the most strikingly diverse animal cell types. One poorly understood example of this diversity is sperm heteromorphism, where males produce multiple distinct morphs of sperm in a single ejaculate. Typically, only one morph is capable of fertilization and the function of the nonfertilizing morph, called parasperm, remains to be elucidated. Sperm heteromorphism has multiple independent origins, including Lepidoptera (moths and butterflies), where males produce a fertilizing eupyrene sperm and an apyrene parasperm, which lacks a nucleus and nuclear DNA. Here we report a comparative proteomic analysis of eupyrene and apyrene sperm between two distantly related lepidopteran species, the monarch butterfly (Danaus plexippus) and Carolina sphinx moth (Manduca sexta). In both species, we identified ∼700 sperm proteins, with half present in both morphs and the majority of the remainder observed only in eupyrene sperm. Apyrene sperm thus have a distinctly less complex proteome. Gene ontology (GO) analysis revealed proteins shared between morphs tend to be associated with canonical sperm cell structures (e.g., flagellum) and metabolism (e.g., ATP production). GO terms for morph-specific proteins broadly reflect known structural differences, but also suggest a role for apyrene sperm in modulating female neurobiology. Comparative analysis indicates that proteins shared between morphs are most conserved between species as components of sperm, whereas morph-specific proteins turn over more quickly, especially in apyrene sperm. The rapid divergence of apyrene sperm content is consistent with a relaxation of selective constraints associated with fertilization and karyogamy. On the other hand, parasperm generally exhibit greater evolutionary lability, and our observations may therefore reflect adaptive responses to shifting regimes of sexual selection.
Description
This article has been accepted for publication in Genome Biology and Evolution Published by Oxford University Press.
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
Collections
Citation
Emma Whittington, Timothy L Karr, Andrew J Mongue, Steve Dorus, James R Walters, Evolutionary Proteomics Reveals Distinct Patterns of Complexity and Divergence between Lepidopteran Sperm Morphs, Genome Biology and Evolution, Volume 11, Issue 7, July 2019, Pages 1838–1846, https://doi.org/10.1093/gbe/evz080
Items in KU ScholarWorks are protected by copyright, with all rights reserved, unless otherwise indicated.
We want to hear from you! Please share your stories about how Open Access to this item benefits YOU.