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Worthy FR, Schaefer DA, Wanasinghe D, Xu JC, Wang LS, Wang XY. Acquisition of green algal photobionts enables both chlorolichens and chloro-cyanolichens to activate photosynthesis at low humidity without liquid water. AOB PLANTS 2024; 16:plae025. [PMID: 38770101 PMCID: PMC11102867 DOI: 10.1093/aobpla/plae025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2024] [Accepted: 04/23/2024] [Indexed: 05/22/2024]
Abstract
Cyanobacteria require liquid water for photosynthesis, whereas green algae can photosynthesise with water vapour alone. We discovered that several Lobaria spp. which normally have cyanobacteria as the sole photobiont, in some regions of the trans-Himalayas also harboured green algae. We tested whether green algal acquisition was: limited to high elevations; obtained from neighbouring chloro-Lobaria species; enabled photosynthesis at low humidity. Lobaria spp. were collected from 2000 to 4000 m elevation. Spectrophotometry quantified green algal abundance by measuring chlorophyll b (absent in cyanobacteria). Thalli cross-sections visually confirmed green algal presence. We sequenced gene regions: Lobaria (ITS-EF-1α-RPB2), green algae (18S-RBC-L) and Nostoc (16S). Phylogenetic analysis determined myco-photobiont associations. We used a custom closed-circuit gas exchange system with an infrared gas analyser to measure CO2 exchange rates for desiccated specimens at 33%, 76%, 86% and 98% humidity. Cross-sections revealed that the photobiont layers in putative cyano-Lobaria contained both cyanobacteria and green algae, indicating that they should be considered chloro-cyanolichens. Chloro-Lobaria had no visible cephalodia nor cyanobacteria in the photobiont layer. Chloro-Lobaria and chloro-cyano-Lobaria had comparable levels of chlorophyll b. Chloro-Lobaria usually contained Symbiochloris. Chloro-cyano-Lobaria mainly associated with Parachloroidium and Nostoc; infrequently with Symbiochloris, Apatococcus, Chloroidium, Pseudochlorella, Trebouxia. Sequences from two green algal genera were obtained from within some thalli. Desiccated specimens of every Lobaria species could attain net photosynthesis with light exposure and 33% humidity. CO2 exchange dynamics over a five-day period differed between species. At all elevations, chloro-cyano-Lobaria spp. had abundant green algae in the photobiont layer, but green algal strains mostly differed to those of chloro-Lobaria spp. Both chloro-Lobaria and chloro-cyano-Lobaria were capable of conducting photosynthesis without liquid water. The data strongly suggest that they attained positive net photosynthesis.
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Affiliation(s)
- Fiona Ruth Worthy
- Yunnan Key Laboratory for Fungal Diversity and Green Development, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Kunming, Yunnan 650201, China
- Honghe Centre for Mountain Futures, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Kunming, Yunnan 650201, China
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Kunming, Yunnan 650201, China
| | - Douglas Allen Schaefer
- Honghe Centre for Mountain Futures, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Kunming, Yunnan 650201, China
| | - Dhanushka Wanasinghe
- Honghe Centre for Mountain Futures, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Kunming, Yunnan 650201, China
- Department of Soil Science, College of Food and Agriculture Sciences, King Saud University, Riyadh 11362, Saudi Arabia
| | - Jian Chu Xu
- Honghe Centre for Mountain Futures, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Kunming, Yunnan 650201, China
| | - Li Song Wang
- Yunnan Key Laboratory for Fungal Diversity and Green Development, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Kunming, Yunnan 650201, China
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Kunming, Yunnan 650201, China
| | - Xin Yu Wang
- Yunnan Key Laboratory for Fungal Diversity and Green Development, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Kunming, Yunnan 650201, China
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Kunming, Yunnan 650201, China
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Valim HF, Grande FD, Wong ELY, Schmitt I. Circadian clock- and temperature-associated genes contribute to overall genomic differentiation along elevation in lichenized fungi. Mol Ecol 2024; 33:e17252. [PMID: 38146927 DOI: 10.1111/mec.17252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 11/24/2023] [Accepted: 12/11/2023] [Indexed: 12/27/2023]
Abstract
Circadian regulation is linked to local environmental adaptation, and many species with broad climatic niches display variation in circadian genes. Here, we hypothesize that lichenizing fungi occupying different climate zones tune their metabolism to local environmental conditions with the help of their circadian systems. We study two species of the genus Umbilicaria occupying similar climatic niches (Mediterranean and the cold temperate) in different continents. Using homology to Neurospora crassa genes, we identify gene sets associated with circadian rhythms (11 core, 39 peripheral genes) as well as temperature response (37 genes). Nucleotide diversity of these genes is significantly correlated with mean annual temperature, minimum temperature of the coldest month and mean temperature of the coldest quarter. Furthermore, we identify altitudinal clines in allele frequencies in several non-synonymous substitutions in core clock components, for example, white collar-like, frh-like and various ccg-like genes. A dN/dS approach revealed a few significant peripheral clock- and temperature-associated genes (e.g. ras-1-like, gna-1-like) that may play a role in fine-tuning the circadian clock and temperature-response machinery. An analysis of allele frequency changes demonstrated the strongest evidence for differentiation above the genomic background in the clock-associated genes in U. pustulata. These results highlight the likely relevance of the circadian clock in environmental adaptation, particularly frost tolerance, of lichens. Whether or not the fungal clock modulates the symbiotic interaction within the lichen consortium remains to be investigated. We corroborate the finding of genetic variation in clock components along altitude-not only latitude-as has been reported in other species.
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Affiliation(s)
- Henrique F Valim
- Senckenberg Biodiversity and Climate Research Centre, Frankfurt am Main, Germany
- LOEWE Centre for Translational Biodiversity Genomics (LOEWE-TBG), Frankfurt am Main, Germany
| | - Francesco Dal Grande
- Senckenberg Biodiversity and Climate Research Centre, Frankfurt am Main, Germany
- LOEWE Centre for Translational Biodiversity Genomics (LOEWE-TBG), Frankfurt am Main, Germany
- Department of Biology, University of Padova, Padua, Italy
| | - Edgar L Y Wong
- Senckenberg Biodiversity and Climate Research Centre, Frankfurt am Main, Germany
- LOEWE Centre for Translational Biodiversity Genomics (LOEWE-TBG), Frankfurt am Main, Germany
| | - Imke Schmitt
- Senckenberg Biodiversity and Climate Research Centre, Frankfurt am Main, Germany
- LOEWE Centre for Translational Biodiversity Genomics (LOEWE-TBG), Frankfurt am Main, Germany
- Institute of Ecology, Evolution and Diversity, Goethe University Frankfurt, Frankfurt am Main, Germany
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Pino-Bodas R, Blázquez M, de los Ríos A, Pérez-Ortega S. Myrmecia, Not Asterochloris, Is the Main Photobiont of Cladonia subturgida ( Cladoniaceae, Lecanoromycetes). J Fungi (Basel) 2023; 9:1160. [PMID: 38132761 PMCID: PMC10744234 DOI: 10.3390/jof9121160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Revised: 11/24/2023] [Accepted: 11/29/2023] [Indexed: 12/23/2023] Open
Abstract
This study explores the diversity of photobionts associated with the Mediterranean lichen-forming fungus Cladonia subturgida. For this purpose, we sequenced the whole ITS rDNA region by Sanger using a metabarcoding method for ITS2. A total of 41 specimens from Greece, Italy, France, Portugal, and Spain were studied. Additionally, two specimens from Spain were used to generate four cultures. Our molecular studies showed that the genus Myrmecia is the main photobiont of C. subturgida throughout its geographic distribution. This result contrasts with previous studies, which indicated that the main photobiont for most Cladonia species is Asterochloris. The identity of Myrmecia was also confirmed by ultrastructural studies of photobionts within the lichen thalli and cultures. Photobiont cells showed a parietal chloroplast lacking a pyrenoid, which characterizes the species in this genus. Phylogenetic analyses indicate hidden diversity within this genus. The results of amplicon sequencing showed the presence of multiple ASVs in 58.3% of the specimens studied.
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Affiliation(s)
- Raquel Pino-Bodas
- Biodiversity and Conservation Area, Department of Biology and Geology, Physics and Inorganic Chemistry, Rey Juan Carlos University, C/Tulipán s/n, 28933 Móstoles, Spain
- Royal Botanic Gardens, Kew, Richmond, London TW9 3DS, UK
| | - Miguel Blázquez
- Department of Mycology, Real Jardín Botánico (CSIC), 28014 Madrid, Spain; (M.B.); (S.P.-O.)
| | | | - Sergio Pérez-Ortega
- Department of Mycology, Real Jardín Botánico (CSIC), 28014 Madrid, Spain; (M.B.); (S.P.-O.)
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Steinová J, Holien H, Košuthová A, Škaloud P. An Exception to the Rule? Could Photobiont Identity Be a Better Predictor of Lichen Phenotype than Mycobiont Identity? J Fungi (Basel) 2022; 8:jof8030275. [PMID: 35330277 PMCID: PMC8953480 DOI: 10.3390/jof8030275] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 03/02/2022] [Accepted: 03/07/2022] [Indexed: 11/16/2022] Open
Abstract
With rare exceptions, the shape and appearance of lichen thalli are determined by the fungal partner; thus, mycobiont identity is normally used for lichen identification. However, it has repeatedly been shown in recent decades that phenotypic data often does not correspond with fungal gene evolution. Here, we report such a case in a three-species complex of red-fruited Cladonia lichens, two of which clearly differ morphologically, chemically, ecologically and in distribution range. We analysed 64 specimens of C. bellidiflora, C. polydactyla and C. umbricola, mainly collected in Europe, using five variable mycobiont-specific and two photobiont-specific molecular markers. All mycobiont markers exhibited very low variability and failed to separate the species. In comparison, photobiont identity corresponded better with lichen phenotype and separated esorediate C. bellidiflora from the two sorediate taxa. These results can be interpreted either as an unusual case of lichen photomorphs or as an example of recent speciation, in which phenotypic differentiation precedes the separation of the molecular markers. We hypothesise that association with different photobionts, which is probably related to habitat differentiation, may have triggered speciation in the mycobiont species.
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Affiliation(s)
- Jana Steinová
- Department of Botany, Faculty of Science, Charles University in Prague, Benátská 2, 128 01 Prague, Czech Republic;
- Correspondence:
| | - Håkon Holien
- Faculty of Biosciences and Aquaculture, Nord University, Pb 2501, NO-7729 Steinkjer, Norway;
| | - Alica Košuthová
- Department of Botany, Swedish Museum of Natural History, P.O. Box 50007, SE-104 05 Stockholm, Sweden;
| | - Pavel Škaloud
- Department of Botany, Faculty of Science, Charles University in Prague, Benátská 2, 128 01 Prague, Czech Republic;
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