Open AccessNostoc Talks Back: Temporal Patterns of Differential Gene Expression During Establishment of Anthoceros-Nostoc Symbiosis
Author(s) -
Poulami Chatterjee,
Peter Schafran,
FayWei Li,
John C. Meeks
Publication year - 2022
Publication title -
molecular plant-microbe interactions
Language(s) - English
Resource type - Journals
eISSN - 1943-7706
pISSN - 0894-0282
DOI - 10.1094/mpmi-05-22-0101-r
Subject(s) - biology , gene , gene expression , symbiosis , cyanobacteria , transcription (linguistics) , promoter , nostoc , photosynthesis , downregulation and upregulation , botany , microbiology and biotechnology , genetics , bacteria , linguistics , philosophy
Endosymbiotic associations between hornworts and nitrogen-fixing cyanobacteria form when the plant is limited for combined nitrogen (N). We generated RNA-seq data to examine temporal gene expression patterns during the culturing of N-starved Anthoceros punctatus in the absence and the presence of symbiotic cyanobacterium Nostoc punctiforme . In symbiont-free A . punctatus gametophytes, N starvation caused downregulation of chlorophyll content and chlorophyll fluorescence characteristics as well as transcription of photosynthesis-related genes. This downregulation was reversed in A . punctatus cocultured with N . punctiforme , corresponding to the provision by the symbiont of N 2 -derived NH 4 + , which commenced within 5 days of coculture and reached a maximum by 14 days. We also observed transient increases in transcription of ammonium and nitrate transporters in a N . punctiforme -dependent manner as well as that of a SWEET transporter that was initially independent of N 2 -derived NH 4 + . The temporal patterns of differential gene expression indicated that N . punctiforme transmits signals that impact gene expression to A . punctatus both prior to and after its provision of fixed N. This study is the first illustrating the temporal patterns of gene expression during establishment of an endosymbiotic nitrogen-fixing association in this monophyletic evolutionary lineage of land plants. [Formula: see text] Copyright © 2022 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.