Preprint Article Version 1 This version is not peer-reviewed

A Symbiont’s Guide to the Germline

Version 1 : Received: 14 January 2019 / Approved: 15 January 2019 / Online: 15 January 2019 (09:55:25 CET)

How to cite: Russell, S.; Chappell, L.; Sullivan, W.. A Symbiont’s Guide to the Germline. Preprints 2019, 2019010149 (doi: 10.20944/preprints201901.0149.v1). Russell, S.; Chappell, L.; Sullivan, W.. A Symbiont’s Guide to the Germline. Preprints 2019, 2019010149 (doi: 10.20944/preprints201901.0149.v1).

Abstract

Microbial symbioses exhibit astounding adaptations, yet all symbionts face the problem of how to reliably associate with host offspring every generation. A common strategy is vertical transmission, in which symbionts are directly transmitted from the female to her offspring. The diversity of symbionts and vertical transmission mechanisms is as expansive as the diversity of eukaryotic host taxa that house them. However, there are several common themes among these mechanisms based on the degree to which symbionts associate with the host germline during transmission. In this review, we detail three distinct vertical transmission strategies, starting with associations that are transmitted from host somatic cells to offspring somatic cells, either due to lacking a germline or avoiding it. A second strategy involves somatically-localized symbionts that migrate into the germline during host development. The third strategy we discuss is one in which the symbiont maintains continuous association with the germline throughout development. Unexpectedly, the vast majority of documented vertically inherited symbionts rely on the second strategy: soma-to-germline migration. Given that not all eukaryotes contain a sequestered germline and instead produce offspring from somatic stem cell lineages, this soma-to-germline migration is discussed in the context of multicellular evolution. Lastly, as recent genomics data have revealed an abundance of horizontal gene transfer events from symbiotic and non-symbiotic bacteria to host genomes, we discuss their impact on eukaryotic host evolution.

Subject Areas

endosymbiosis, germline, vertical transmission, cell-to-cell transfer

Comments (0)

We encourage comments and feedback from a broad range of readers. See criteria for comments and our diversity statement.

Leave a public comment
Send a private comment to the author(s)
Views 0
Downloads 0
Comments 0
Metrics 0


×
Alerts
Notify me about updates to this article or when a peer-reviewed version is published.