Microorganisms in the reproductive tissues of arthropods

Abstract

Microorganisms that reside within or transmit through arthropod reproductive tissues have profound impacts on host reproduction, health and evolution. In this Review, we discuss select principles of the biology of microorganisms in arthropod reproductive tissues, including bacteria, viruses, protists and fungi. We review models of specific symbionts, routes of transmission, and the physiological and evolutionary outcomes for both hosts and microorganisms. We also identify areas in need of continuing research, to answer the fundamental questions that remain in fields within and beyond arthropod–microorganism associations. New opportunities for research in this area will drive a broader understanding of major concepts as well as the biodiversity, mechanisms and translational applications of microorganisms that interact with host reproductive tissues.

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Fig. 1: Example microorganisms associated with arthropod reproductive tissues.
Fig. 2: Transmission routes of microorganisms in the reproductive tract in arthropods.
Fig. 3: Effects on the genomes and transcriptomes of hosts and microorganisms.

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Acknowledgements

The authors thank M. I. Hood-Pishchany, K. Ngo, B. Leigh and the journal editorial team for constructive comments. Work in the authors’ laboratory was supported by awards from the National Institutes of Health (NIH; R21 AI133522) and the Vanderbilt Microbiome Initiative to S.R.B, as well as by NIH grant F31 AI143152 to J.I.P.

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S.R.B. and J.I.P. wrote the article, reviewed and edited the manuscript before submission. J.I.P initially drafted the article and researched data for the article.

Correspondence to Jessamyn I. Perlmutter or Seth R. Bordenstein.

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Glossary

Bacteriocytes

Or mycetocytes. Specialized fat cells found in some insects that contain endosymbiotic organisms, especially bacteria (or fungi), that provide essential nutrients or functions for their hosts. Bacteriocytes or mycetocytes together form bacteriomes or mycetomes, which are specialized organs in some insects that house the symbionts.

Blastulae

Hollow spheres of cells surrounding a cavity of fluid, comprising the early stages in the development of embryos.

Ovipositor

The tube-like organ at the bottom of the abdomen that female arthropods use to lay eggs.

Spermathecae

An organ in the female reproductive tract in insects that is used to store sperm post-mating.

Matriline

The exclusively female line of descent from a female ancestor to a female descendant.

Hologenome

The genome of a holobiont, which is the host and all its microbial symbionts. The hologenome includes the genomes of the host and its microorganisms.

Vas deferens

A muscular tube in the human male reproductive tract that carries sperm to the ejaculatory duct.

Coronal sulcus

The indented groove at the base of the human penis head.

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Perlmutter, J.I., Bordenstein, S.R. Microorganisms in the reproductive tissues of arthropods. Nat Rev Microbiol 18, 97–111 (2020). https://doi.org/10.1038/s41579-019-0309-z

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