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Distinctive characters of Nostoc genomes in cyanolichens.

ABSTRACT: BACKGROUND:Cyanobacteria of the genus Nostoc are capable of forming symbioses with a wide range of organism, including a diverse assemblage of cyanolichens. Only certain lineages of Nostoc appear to be able to form a close, stable symbiosis, raising the question whether symbiotic competence is determined by specific sets of genes and functionalities. RESULTS:We present the complete genome sequencing, annotation and analysis of two lichen Nostoc strains. Comparison with other Nostoc genomes allowed identification of genes potentially involved in symbioses with a broad range of partners including lichen mycobionts. The presence of additional genes necessary for symbiotic competence is likely reflected in larger genome sizes of symbiotic Nostoc strains. Some of the identified genes are presumably involved in the initial recognition and establishment of the symbiotic association, while others may confer advantage to cyanobionts during cohabitation with a mycobiont in the lichen symbiosis. CONCLUSIONS:Our study presents the first genome sequencing and genome-scale analysis of lichen-associated Nostoc strains. These data provide insight into the molecular nature of the cyanolichen symbiosis and pinpoint candidate genes for further studies aimed at deciphering the genetic mechanisms behind the symbiotic competence of Nostoc. Since many phylogenetic studies have shown that Nostoc is a polyphyletic group that includes several lineages, this work also provides an improved molecular basis for demarcation of a Nostoc clade with symbiotic competence.

SUBMITTER: Gagunashvili AN

PROVIDER: S-EPMC5987646 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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Distinctive characters of Nostoc genomes in cyanolichens.

Gagunashvili Andrey N AN Andrésson Ólafur S ÓS

BMC genomics 20180605 1

<h4>Background</h4>Cyanobacteria of the genus Nostoc are capable of forming symbioses with a wide range of organism, including a diverse assemblage of cyanolichens. Only certain lineages of Nostoc appear to be able to form a close, stable symbiosis, raising the question whether symbiotic competence is determined by specific sets of genes and functionalities.<h4>Results</h4>We present the complete genome sequencing, annotation and analysis of two lichen Nostoc strains. Comparison with other Nosto ...[more]

PMID: 29866043

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Dataset Information

Distinctive characters of Nostoc genomes in cyanolichens.

Publications

Distinctive characters of Nostoc genomes in cyanolichens.

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