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Dos Santos WL, Medina-Ramos A, Greenwood J, Pôrto KC, Pinheiro F, Stark LR. Understanding desiccation tolerance and sex-specific responses in Bryum argenteum: insights from phenological phases and physiological analyses. ANNALS OF BOTANY 2024; 134:351-364. [PMID: 38702965 PMCID: PMC11232512 DOI: 10.1093/aob/mcae071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Accepted: 05/01/2024] [Indexed: 05/06/2024]
Abstract
BACKGROUND AND AIMS Desiccation tolerance (DT) is crucial for survival in arid environments, where organisms develop strategies in reproduction, maintenance and defence to cope with water scarcity. Therefore, investigating the relationship between reproduction and DT is essential to understand the ecology and adaptive strategies of species. This study explores the connection between the development of male and female gametangia in the moss Bryum argenteum and the decrease in DT during the progression of phenological phases in gametangia and protonema. METHODS Samples collected from a dry tropical forest in Brazil were cultivated, cloned and subjected to desiccation. Subsequently, the physiological parameters of shoots and protonemata were analysed. Shoot and protonema regeneration were monitored for 28 d after the physiological analyses. Both phases were subjected to control and desiccation treatments. KEY RESULTS Significant effects of desiccation and sex on the physiological parameters and regeneration capacity of shoots and protonemata were found. Male shoots generally exhibited lower values of Fv/Fm (quantum efficiency of photosystem II) and ϕPSII (effective quantum yield of photosystem II), while females demonstrated higher values and better recovery after desiccation. Protonemata also showed variation in Fv/Fm over time and with sex, with no significant differences in ϕPSII between them. Desiccated male shoots had higher mortality rates and produced fewer new shoots. For females, the regeneration patterns varied between the desiccation-exposed groups and the control, with decreased shoot production, and some protonemata growing into filaments without forming shoots. CONCLUSION These findings improve our understanding of the ecological responses of bryophytes to desiccation stress and provide insights into their adaptive strategies in challenging environments, such as the possible rarity of males in dioicous moss populations.
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Affiliation(s)
- Wagner Luiz Dos Santos
- Graduate Program in Ecology, Biology Institute, Department of Plant Biology, Universidade Estadual de Campinas, Monteiro Lobato 255, Campinas, SP 13083-862, Brazil
| | - Andrea Medina-Ramos
- School of Life Sciences, University of Nevada, 4505 Maryland Parkway, Las Vegas, NV 89154-4004, USA
| | - Joshua Greenwood
- School of Life Sciences, University of Nevada, 4505 Maryland Parkway, Las Vegas, NV 89154-4004, USA
| | - Kátia Cavalcanti Pôrto
- Biosciences Center, Department of Botany, Universidade Federal de Pernambuco, Moraes Rego Av., s/n, Recife, PE 50670-901, Brazil
| | - Fábio Pinheiro
- Graduate Program in Ecology, Biology Institute, Department of Plant Biology, Universidade Estadual de Campinas, Monteiro Lobato 255, Campinas, SP 13083-862, Brazil
| | - Lloyd R Stark
- School of Life Sciences, University of Nevada, 4505 Maryland Parkway, Las Vegas, NV 89154-4004, USA
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Coe K, Carter B, Slate M, Stanton D. Moss functional trait ecology: Trends, gaps, and biases in the current literature. AMERICAN JOURNAL OF BOTANY 2024; 111:e16288. [PMID: 38366744 DOI: 10.1002/ajb2.16288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 12/20/2023] [Accepted: 12/21/2023] [Indexed: 02/18/2024]
Abstract
Functional traits are critical tools in plant ecology for capturing organism-environment interactions based on trade-offs and making links between organismal and ecosystem processes. While broad frameworks for functional traits have been developed for vascular plants, we lack the same for bryophytes, despite an escalation in the number of studies on bryophyte functional trait in the last 45 years and an increased recognition of the ecological roles bryophytes play across ecosystems. In this review, we compiled data from 282 published articles (10,005 records) that focused on functional traits measured in mosses and sought to examine trends in types of traits measured, capture taxonomic and geographic breadth of trait coverage, reveal biases in coverage in the current literature, and develop a bryophyte-function index (BFI) to describe the completeness of current trait coverage and identify global gaps to focus research efforts. The most commonly measured response traits (those related to growth/reproduction in individual organisms) and effect traits (those that directly affect community/ecosystem scale processes) fell into the categories of morphology (e.g., leaf area, shoot height) and nutrient storage/cycling, and our BFI revealed that these data were most commonly collected from temperate and boreal regions of Europe, North America, and East Asia. However, fewer than 10% of known moss species have available functional trait information. Our synthesis revealed a need for research on traits related to ontogeny, sex, and intraspecific plasticity and on co-measurement of traits related to water relations and bryophyte-mediated soil processes.
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Affiliation(s)
- Kirsten Coe
- Department of Biology, Middlebury, VT, 05753, USA
| | - Benjamin Carter
- Department of Biological Sciences, San Jose State University, San Jose, CA, 95192, USA
| | - Mandy Slate
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO, 80309, USA
- Present address: Department of Evolution, Ecology, and Organismal Biology, The Ohio State University, Columbus, OH, 43210, USA
| | - Daniel Stanton
- Department of Ecology Evolution and Behavior, University of Minnesota, Saint Paul, MN, 55108, USA
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Li T, Zhu S, Li Y, Yao J, Wang C, Fang S, Pan J, Chen W, Zhang Y. Characteristic of GEX1 genes reveals the essential roles for reproduction in cotton. Int J Biol Macromol 2023; 253:127645. [PMID: 37879575 DOI: 10.1016/j.ijbiomac.2023.127645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Revised: 09/30/2023] [Accepted: 10/22/2023] [Indexed: 10/27/2023]
Abstract
GEX1 (gamete expressed 1) proteins are critical membrane proteins conserved among flowering plants that are involved in the nuclear fusion and embryonic development. Herein, we identified the 32 GEX1 proteins from representative land plants. In cotton, GEX1 genes expressed in various tissues across all stages of the life cycle, especially in pollen. Subcellular localization indicated the position of GhGEX1 protein was localized in the endoplasmic reticulum. Experimental research has demonstrated that GhGEX1 has the potential to improve the partial abortion phenotype in Arabidopsis. CRISPR/Cas9-mediated knockout of GhGEX1 exhibited the seed abortion. Paraffin section of the ovule revealed that the polar nuclear fusion of ghgex1 plants remains at a standstill when the wild type has developed into a normal embryo. Comparative transcriptome analysis showed that the DEGs of reproductive-related processes and membrane-related processes were repressed in the pollen of knockout lines. The predicted protein interactions showed that GhGEX1 probably functioned through interactions with proteins related to reproduction and membrane. From all these investigations, it was possible to conclude that the GEX1 proteins are evolutionarily conserved in flowering plants and elucidated the pivotal roles during fertilization and early embryonic development in cotton.
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Affiliation(s)
- Tengyu Li
- National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, Institute of Cotton Research, Chinese Academy of Agricultural Science, Anyang 455000, China; National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
| | - Shouhong Zhu
- National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, Institute of Cotton Research, Chinese Academy of Agricultural Science, Anyang 455000, China
| | - Yan Li
- National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, Institute of Cotton Research, Chinese Academy of Agricultural Science, Anyang 455000, China
| | - Jinbo Yao
- National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, Institute of Cotton Research, Chinese Academy of Agricultural Science, Anyang 455000, China
| | - Chenlei Wang
- National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, Institute of Cotton Research, Chinese Academy of Agricultural Science, Anyang 455000, China
| | - Shengtao Fang
- National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, Institute of Cotton Research, Chinese Academy of Agricultural Science, Anyang 455000, China
| | - Jingwen Pan
- National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, Institute of Cotton Research, Chinese Academy of Agricultural Science, Anyang 455000, China
| | - Wei Chen
- National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, Institute of Cotton Research, Chinese Academy of Agricultural Science, Anyang 455000, China.
| | - Yongshan Zhang
- National Key Laboratory of Cotton Bio-breeding and Integrated Utilization, Institute of Cotton Research, Chinese Academy of Agricultural Science, Anyang 455000, China.
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Shortlidge EE, Carey SB, Payton AC, McDaniel SF, Rosenstiel TN, Eppley SM. Microarthropod contributions to fitness variation in the common moss Ceratodon purpureus. Proc Biol Sci 2021; 288:20210119. [PMID: 33784868 PMCID: PMC8059975 DOI: 10.1098/rspb.2021.0119] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
The evolution of sustained plant–animal interactions depends critically upon genetic variation in the fitness benefits from the interaction. Genetic analyses of such interactions are limited to a few model systems, in part because genetic variation may be absent or the interacting species may be experimentally intractable. Here, we examine the role of sperm-dispersing microarthropods in shaping reproduction and genetic variation in mosses. We established experimental mesocosms with known moss genotypes and inferred the parents of progeny from mesocosms with and without microarthropods, using a pooled sequencing approach. Moss reproductive rates increased fivefold in the presence of microarthropods, relative to control mesocosms. Furthermore, the presence of microarthropods increased the total number of reproducing moss genotypes, and changed the rank-order of fitness of male and female moss genotypes. Interestingly, the genotypes that reproduced most frequently did not produce sporophytes with the most spores, highlighting the challenge of defining fitness in mosses. These results demonstrate that microarthropods provide a fitness benefit for mosses, and highlight the potential for biotic dispersal agents to alter fitness among moss genotypes.
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Affiliation(s)
- Erin E Shortlidge
- Department of Biology, Portland State University, PO Box 751, Portland, OR 97202-0751, USA
| | - Sarah B Carey
- Department of Biology, University of Florida, PO Box 118525, Gainesville, FL 32611-8525, USA
| | - Adam C Payton
- Department of Biology, University of Florida, PO Box 118525, Gainesville, FL 32611-8525, USA
| | - Stuart F McDaniel
- Department of Biology, University of Florida, PO Box 118525, Gainesville, FL 32611-8525, USA
| | - Todd N Rosenstiel
- Department of Biology, Portland State University, PO Box 751, Portland, OR 97202-0751, USA
| | - Sarah M Eppley
- Department of Biology, Portland State University, PO Box 751, Portland, OR 97202-0751, USA
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Alonso-García M, Villarreal A. JC, McFarland K, Goffinet B. Population Genomics and Phylogeography of a Clonal Bryophyte With Spatially Separated Sexes and Extreme Sex Ratios. FRONTIERS IN PLANT SCIENCE 2020; 11:495. [PMID: 32457772 PMCID: PMC7226906 DOI: 10.3389/fpls.2020.00495] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Accepted: 04/01/2020] [Indexed: 06/11/2023]
Abstract
The southern Appalachian (SA) is one of the most biodiversity-rich areas in North America and has been considered a refugium for many disjunct plant species, from the last glacial period to the present. Our study focuses on the SA clonal hornwort, Nothoceros aenigmaticus J. C. Villarreal & K. D. McFarland. This hornwort was described from North Carolina and is widespread in the SA, growing on rocks near or submerged in streams in six and one watersheds of the Tennessee (TR) and Alabama (AR) Rivers, respectively. Males and female populations occur in different watersheds, except in the Little Tennessee (TN) River where an isolated male population exists ca. 48 km upstream from the female populations. The sex ratio of 1:0 seems extreme in each population. In this study, we use nuclear and organellar microsatellites from 250 individuals from six watersheds (seven populations) in the SA region and two populations from Mexico (23 individuals). We, then, selected 86 individuals from seven populations and used genotyping by sequencing to sample over 600 bi-allelic markers. Our results suggest that the SA N. aenigmaticus and Mexican plants are a nested within a clade of sexual tropical populations. In the US populations, we confirm an extreme sex ratio and only contiguous US watersheds share genotypes. The phylogenetic analysis of SNP data resolves four clusters: Mexican populations, male plants (Little Pigeon and Pigeon river watersheds) and two clusters of female plants; one from the Little Tennessee and Hiwassee Rivers (TR) and the other from the Ocoee (TR) and Coosa (AR) Rivers. All clusters are highly differentiated (Fst values over 0.9). In addition, our individual assignment analyses and PCAs reflect the phylogenetic results grouping the SA samples in three clades and recovering males and female plants with high genetic differentiation (Fst values between 0.5 and 0.9 using microsatellites and bi-allelic markers). Our results point to Pleistocene events shaping the biogeographical pattern seen in US populations. The extreme sex ratio reflects isolation and highlights the high vulnerability of the populations in the SA.
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Affiliation(s)
| | - Juan Carlos Villarreal A.
- Département de Biologie, Université Laval, Quebec City, QC, Canada
- Smithsonian Tropical Research Institute, Ancón, Panama
| | - Kenneth McFarland
- Department of Ecology and Evolutionary Biology, The University of Tennessee, Knoxville, TN, United States
| | - Bernard Goffinet
- Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT, United States
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Warren SD, Clair LL, Stark LR, Lewis LA, Pombubpa N, Kurbessoian T, Stajich JE, Aanderud ZT. Reproduction and Dispersal of Biological Soil Crust Organisms. Front Ecol Evol 2019. [DOI: 10.3389/fevo.2019.00344] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
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Slate ML, Rosenstiel TN, Eppley SM. Sex-specific morphological and physiological differences in the moss Ceratodon purpureus (Dicranales). ANNALS OF BOTANY 2017; 120:845-854. [PMID: 28981564 PMCID: PMC5714240 DOI: 10.1093/aob/mcx071] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Accepted: 05/15/2017] [Indexed: 05/07/2023]
Abstract
BACKGROUND AND AIMS Dioecy and sexual dimorphism occur in many terrestrial plant species but are especially widespread among the bryophytes. Despite the prevalence of dioecy in non-vascular plants, surprisingly little is known about how fine-scale sex-specific cell and leaf morphological traits are correlated with sex-specific physiology and population sex ratios. Such data are critical to understanding the inter-relationship between sex-specific morphological and physiological characters and how their relationship influences population structure. In this study, these data types were assessed to determine how they vary across three populations within one moss species and whether fine-scale morphological traits scale up to physiological and sex ratio characteristics. METHODS Twenty cell-, leaf- and canopy-level traits and two photochemical measurements were compared between sexes and populations of the dioecious moss Ceratodon purpureus . Field population-expressed sex ratios were obtained for the same populations. KEY RESULTS Male and female plants differed in cell, leaf and photochemical measures. These sexual dimorphisms were female biased, with females having larger and thicker leaves and greater values for chlorophyll fluorescence-based, leaf photochemistry measurements than males. Female traits were also more variable than male traits. Interestingly, field population sex ratios were significantly male biased in two study populations and female biased in the third study population. CONCLUSIONS The results demonstrate that the larger morphology and the greater physiological output of female C. purpureus gametophytes compared with males occurs across populations and is likely to have significant effects on resource allocation and biotic interactions. However, this high level of dimorphism does not explain population sex ratio variation in the three study populations tested. This research lays the groundwork for future studies on how differential sex-specific variation in cell and leaf traits influences bryophyte plant fitness.
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Affiliation(s)
- Mandy L Slate
- Portland State University, Center for Life in Extreme Environments and Department of Biology, PO Box 751, Portland, OR 97202-0751, USA
| | - Todd N Rosenstiel
- Portland State University, Center for Life in Extreme Environments and Department of Biology, PO Box 751, Portland, OR 97202-0751, USA
| | - Sarah M Eppley
- Portland State University, Center for Life in Extreme Environments and Department of Biology, PO Box 751, Portland, OR 97202-0751, USA
- For correspondence. E-mail
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8
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Shortlidge EE, Eppley SM, Kohler H, Rosenstiel TN, Zúñiga GE, Casanova-Katny A. Passive warming reduces stress and shifts reproductive effort in the Antarctic moss, Polytrichastrum alpinum. ANNALS OF BOTANY 2017; 119:27-38. [PMID: 27794516 PMCID: PMC5218369 DOI: 10.1093/aob/mcw201] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Revised: 06/15/2016] [Accepted: 08/05/2016] [Indexed: 05/25/2023]
Abstract
BACKGROUND AND AIMS The Western Antarctic Peninsula is one of the most rapidly warming regions on Earth, and many biotic communities inhabiting this dynamic region are responding to these well-documented climatic shifts. Yet some of the most prevalent organisms of terrestrial Antarctica, the mosses, and their responses to warming have been relatively overlooked and understudied. In this research, the impacts of 6 years of passive warming were investigated using open top chambers (OTCs), on moss communities of Fildes Peninsula, King George Island, Antarctica. METHODS The effects of experimental passive warming on the morphology, sexual reproductive effort and stress physiology of a common dioicous Antarctic moss, Polytrichastrum alpinum ,: were tested, gaining the first species-specific mechanistic insight into moss responses to warming in the Antarctic. Additionally community analyses were conducted examining the impact of warming on overall moss percentage cover and sporophyte production in intact Antarctic moss communities. KEY RESULTS Our results show a generally greater percentage moss cover under warming conditions as well as increased gametangia production in P. alpinum Distinct morphological and physiological shifts in P. alpinum were found under passive warming compared with those without warming: warmed mosses reduced investment in cellular stress defences, but invested more towards primary productivity and gametangia development. CONCLUSIONS Taken together, results from this study of mosses under passive warming imply that in ice-free moss-dominated regions, continued climate warming will probably have profound impacts on moss biology and colonization along the Western Antarctic Peninsula. Such findings highlight the fundamental role that mosses will play in influencing the terrestrialization of a warming Antarctica.
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Affiliation(s)
- Erin E Shortlidge
- Department of Biology, Portland State University, Portland, OR 97201, USA
| | - Sarah M Eppley
- Department of Biology and the Center for Life in Extreme Environments, Portland State University, Portland, OR 97207, USA
| | - Hans Kohler
- Department of Chemistry and Biology, University of Santiago, Alameda 3363 Santiago, Chile
| | - Todd N Rosenstiel
- Department of Biology and the Center for Life in Extreme Environments, Portland State University, Portland, OR 97207, USA
| | - Gustavo E Zúñiga
- Department of Chemistry and Biology, University of Santiago, Alameda 3363 Santiago, Chile
| | - Angélica Casanova-Katny
- Department of Chemistry and Biology, University of Santiago, Alameda 3363 Santiago, Chile
- Program in Environmental Studies (NEA), School of Environmental Science, Natural Resources Faculty, Catholic University of Temuco, Rudecindo Ortega 02950, Temuco, Chile
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Horst NA, Reski R. Microscopy of Physcomitrella patens sperm cells. PLANT METHODS 2017; 13:33. [PMID: 28491120 PMCID: PMC5424408 DOI: 10.1186/s13007-017-0186-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Accepted: 05/02/2017] [Indexed: 05/03/2023]
Abstract
BACKGROUND Archegoniates (bryophytes, ferns and gymnosperms), such as the moss Physcomitrella patens, possess freely motile sperm cells (spermatozoids) which reach the egg cell via surface water. Although these motile flagellated sperm cells are a traditional botanical subject, they have not been thoroughly analysed in the flagship non-seed plant model species P. patens. Protocols are required to determine the behaviour of wild type sperms as a prerequisite for future research such as the characterization of mutants or factors that influence sperm number, morphology, viability and motility. RESULTS Here, we present protocols for the observation of fixed, as well as live sperms utilizing a standard microscope at intermediate magnifications. Fixed samples can be used for the fast assessment of sperm number and morphology. To determine functionality, the observation of live sperms is required. Protocols for determining both sperm motility and viability are provided, allowing both parameters to be distinguished. CONCLUSIONS These step-by-step protocols are particularly useful for researchers so far not familiar with the analysis of motile gametes and are meant to aid the establishment and improvement of these analyses in order to stimulate research on spermatogenesis in the moss model species P. patens.
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Affiliation(s)
- Nelly A. Horst
- Plant Biotechnology, Faculty of Biology, University of Freiburg, Schaenzlestr. 1, 79104 Freiburg, Germany
| | - Ralf Reski
- Plant Biotechnology, Faculty of Biology, University of Freiburg, Schaenzlestr. 1, 79104 Freiburg, Germany
- BIOSS – Centre for Biological Signalling Studies, University of Freiburg, Schaenzlestr. 18, 79104 Freiburg, Germany
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Stark LR, McLetchie DN, Greenwood JL, Eppley SM. Moss antheridia are desiccation tolerant: Rehydration dynamics influence sperm release in Bryum argenteum. AMERICAN JOURNAL OF BOTANY 2016; 103:856-64. [PMID: 27208354 DOI: 10.3732/ajb.1600026] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Accepted: 04/08/2016] [Indexed: 05/10/2023]
Abstract
PREMISE OF THE STUDY Free-living sperm of mosses are known to be partially desiccation tolerant. We hypothesized that mature moss antheridia should also tolerate desiccation and that rehydration to partial turgor (prehydration) or rehydration to full turgor (rehydration) before immersion in water is required for full recovery from any damaging effects of prior desiccation. METHODS Bryum argenteum (silvery-thread moss) was grown in continuous culture for several months, produced mature perigonia (clusters of antheridia), and these were subjected to a slow rate of drying (∼36 h from full turgor to desiccation) and equilibration with 50% relative humidity. Perigonia were prehydrated (exposed to a saturated atmosphere) or rehydrated (planted upright in saturated media) for 0, 45, 90, 135, 180, and 1440 min, then immersed in sterile water. Time to first sperm mass release, number of antheridia releasing sperm masses, and the integrity of the first sperm mass released were assessed. KEY RESULTS Rehydration of dried antheridia for at least 3 h before immersion in water resulted in antheridia functioning similar to control undried antheridia. Compared with rehydration, prehydration was not effective in the recovery of antheridia from desiccation. CONCLUSIONS For the first time, moss antheridia are shown to be fully desiccation tolerant at a functional level, capable of releasing fully functional sperm following a slow drying event provided the antheridia are allowed to rehydrate at least 3 h before immersion in water.
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Affiliation(s)
- Lloyd R Stark
- School of Life Sciences, University of Nevada, 4505 Maryland Parkway, Las Vegas, Nevada 89154-4004 USA
| | - D Nicholas McLetchie
- Department of Biology, 101 Morgan Building, University of Kentucky, Lexington, Kentucky 40506-0225 USA
| | - Joshua L Greenwood
- School of Life Sciences, University of Nevada, 4505 Maryland Parkway, Las Vegas, Nevada 89154-4004 USA
| | - Sarah M Eppley
- Department of Biology, Portland State University, P.O. Box 751, Portland, Oregon 97207 USA
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Laenen B, Machac A, Gradstein SR, Shaw B, Patiño J, Désamoré A, Goffinet B, Cox CJ, Shaw AJ, Vanderpoorten A. Increased diversification rates follow shifts to bisexuality in liverworts. THE NEW PHYTOLOGIST 2016; 210:1121-1129. [PMID: 27074401 DOI: 10.1111/nph.13835] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Accepted: 12/01/2015] [Indexed: 06/05/2023]
Abstract
Shifts in sexual systems are one of the key drivers of species diversification. In contrast to angiosperms, unisexuality prevails in bryophytes. Here, we test the hypotheses that bisexuality evolved from an ancestral unisexual condition and is a key innovation in liverworts. We investigate whether shifts in sexual systems influence diversification using hidden state speciation and extinction analysis (HiSSE). This new method compares the effects of the variable of interest to the best-fitting latent variable, yielding robust and conservative tests. We find that the transitions in sexual systems are significantly biased toward unisexuality, even though bisexuality is coupled with increased diversification. Sexual systems are strongly conserved deep within the liverwort tree but become much more labile toward the present. Bisexuality appears to be a key innovation in liverworts. Its effects on diversification are presumably mediated by the interplay of high fertilization rates, massive spore production and long-distance dispersal, which may separately or together have facilitated liverwort speciation, suppressed their extinction, or both. Importantly, shifts in liverwort sexual systems have the opposite effect when compared to angiosperms, leading to contrasting diversification patterns between the two groups. The high prevalence of unisexuality among liverworts suggests, however, a strong selection for sexual dimorphism.
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Affiliation(s)
- Benjamin Laenen
- Department of Ecology, Environment and Plant Sciences, Science for Life Laboratory, Stockholm University, Stockholm, 10691, Sweden
- Department of Conservation Biology and Evolution, Institute of Botany, University of Liège, Liège, 4000, Belgium
| | - Antonin Machac
- Center for Macroecology, Evolution, and Climate, Natural History Museum of Denmark, Universitetsparken 15, DK 2100, Copenhagen, Denmark
- Department of Ecology, Charles University, Vinicna 7, Prague 2, 12844, Czech Republic
- Center for Theoretical Study, Charles University and Academy of Sciences of the Czech Republic, Jilska 1, Prague 1, 11000, Czech Republic
| | - S Robbert Gradstein
- Département Systématique et Evolution, Muséum National d'Histoire Naturelle, Paris, 75005, France
| | - Blanka Shaw
- Department of Biology, Duke University, Durham, NC, 27708, USA
| | - Jairo Patiño
- Department of Conservation Biology and Evolution, Institute of Botany, University of Liège, Liège, 4000, Belgium
| | - Aurélie Désamoré
- Department of Conservation Biology and Evolution, Institute of Botany, University of Liège, Liège, 4000, Belgium
- Department of Zoology, Naturhistoriska Riksmuseet, Stockholm, 10405, Sweden
| | - Bernard Goffinet
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT, 06269, USA
| | - Cymon J Cox
- Centro de Ciências do Mar (CCMAR), Universidade do Algarve, Campus de Gambelas, Faro, 8005-139, Portugal
| | - A Jonathan Shaw
- Department of Biology, Duke University, Durham, NC, 27708, USA
| | - Alain Vanderpoorten
- Department of Conservation Biology and Evolution, Institute of Botany, University of Liège, Liège, 4000, Belgium
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12
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Zúñiga-González P, Zúñiga GE, Pizarro M, Casanova-Katny A. Soluble carbohydrate content variation in Sanionia uncinata and Polytrichastrum alpinum, two Antarctic mosses with contrasting desiccation capacities. Biol Res 2016; 49:6. [PMID: 26823072 PMCID: PMC4731983 DOI: 10.1186/s40659-015-0058-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Accepted: 11/27/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Cryptogamic vegetation dominates the ice-free areas along the Antarctic Peninsula. The two mosses Sanionia uncinata and Polytrichastrum alpinum inhabit soils with contrasting water availability. Sanionia uncinata grows in soil with continuous water supply, while P. alpinum grows in sandy, non-flooded soils. Desiccation and rehydration experiments were carried out to test for differences in the rate of water loss and uptake, with non-structural carbohydrates analysed to test their role in these processes. RESULTS Individual plants of S. uncinata lost water 60 % faster than P. alpinum; however, clumps of S. uncinata took longer to dry than those of P. alpinum (11 vs. 5 h, respectively). In contrast, rehydration took less than 10 min for both mosses. Total non-structural carbohydrate content was higher in P. alpinum than in S. uncinata, but sugar levels changed more in P. alpinum during desiccation and rehydration (60-50 %) when compared to S. uncinata. We report the presence of galactinol (a precursor of the raffinose family) for the first time in P. alpinum. Galactinol was present at higher amounts than all other non-structural sugars. CONCLUSIONS Individual plants of S. uncinata were not able to retain water for long periods but by growing and forming carpets, this species can retain water the longest. In contrast individual P. alpinum plants required more time to lose water than S. uncinata, but as moss cushions they suffered desiccation faster than the later. On the other hand, both species rehydrated very quickly. We found that when both mosses lost 50 % of their water, carbohydrates content remained stable and the plants did not accumulate non-structural carbohydrates during the desiccation prosses as usually occurs in vascular plants. The raffinose family oligosaccarides decreased during desiccation, and increased during rehydration, suggesting they function as osmoprotectors.
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Affiliation(s)
- Paz Zúñiga-González
- Laboratorio de Micología y Micorrizas, Facultad de Ciencias Naturales y Oceanográficas and Laboratorio de Investigación en Agentes Antibacterianos, Facultad de Ciencias Biológicas, Universidad de Concepción, Barrio Universitario s/n, Concepción, Chile.
| | - Gustavo E Zúñiga
- Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago, Alameda, 3363, Santiago, Chile.
| | - Marisol Pizarro
- Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago, Alameda, 3363, Santiago, Chile.
| | - Angélica Casanova-Katny
- Núcleo de Estudios Ambientales, Universidad Católica de Temuco, Casilla 15-D, Temuco, Chile.
- Facultad de Química y Biología, Universidad de Santiago, Alameda, 3363, Santiago, Chile.
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Mori T, Kawai-Toyooka H, Igawa T, Nozaki H. Gamete Dialogs in Green Lineages. MOLECULAR PLANT 2015; 8:1442-54. [PMID: 26145252 DOI: 10.1016/j.molp.2015.06.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Revised: 06/15/2015] [Accepted: 06/28/2015] [Indexed: 05/20/2023]
Abstract
Gamete fusion is a core process of sexual reproduction and, in both plants and animals, different sex gametes fuse within species. Although most of the molecular factors involved in gamete interaction are still unknown in various sex-possessing eukaryotes, reports of such factors in algae and land plants have been increasing in the past decade. In particular, knowledge of gamete interaction in flowering plants and green algae has increased since the identification of the conserved gamete fusion factor generative cell specific 1/hapless 2 (GCS1/HAP2). GCS1 was first identified as a pollen generative cell-specific transmembrane protein in the lily (Lilium longiflorum), and was then shown to function not only in flowering plant gamete fusion but also in various eukaryotes, including unicellular protists and metazoans. In addition, although initially restricted to Chlamydomonas, knowledge of gamete attachment in flowering plants was also acquired. This review focuses on recent progress in the study of gamete interaction in volvocine green algae and flowering plants and discusses conserved mechanisms of gamete recognition, attachment, and fusion leading to zygote formation.
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Affiliation(s)
- Toshiyuki Mori
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
| | - Hiroko Kawai-Toyooka
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Tomoko Igawa
- Graduate School of Horticulture, Chiba University, 648 Matsudo, Matsudo, Chiba 271-8510, Japan
| | - Hisayoshi Nozaki
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
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14
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Johnson MG, Shaw AJ. Genetic diversity, sexual condition, and microhabitat preference determine mating patterns inSphagnum(Sphagnaceae) peat-mosses. Biol J Linn Soc Lond 2015. [DOI: 10.1111/bij.12497] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Matthew G. Johnson
- Biology Department; Duke University; 130 Science Drive Box 90338 Durham NC 27708 USA
| | - A. Jonathan Shaw
- Biology Department; Duke University; 130 Science Drive Box 90338 Durham NC 27708 USA
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15
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Stark LR, Greenwood JL, Brinda JC, Oliver MJ. The desert moss Pterygoneurum lamellatum (Pottiaceae) exhibits an inducible ecological strategy of desiccation tolerance: effects of rate of drying on shoot damage and regeneration. AMERICAN JOURNAL OF BOTANY 2013; 100:1522-31. [PMID: 23876454 DOI: 10.3732/ajb.1200648] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
PREMISE OF THE STUDY Bryophytes include clades that incorporate constitutive desiccation tolerance, especially terrestrial species. Here we test the hypothesis that the opposing ecological strategy of desiccation tolerance, inducibility, is present in a desert moss, and address this hypothesis by varying rates of drying in a laboratory study. Desiccation tolerance is arguably the most important evolutionary innovation relevant to the colonization of land by plants; increased understanding of the ecological drivers of this trait will eventually illuminate the responsible mechanisms and ultimately open doors to the potential for the application of this trait in cultivated plants. METHODS Plants were cloned, grown in continuous culture (dehardened) for several months, and subjected to rates of drying (drying times) ranging from 30 min to 53 h, rehydrated and tested for recovery using chlorophyll fluorescence, leaf damage, and regeneration of protonema and shoots. KEY RESULTS Rate of drying significantly affected all recovery responses, with very rapid drying rates severely damaging the entire shoot except the shoot apex and resulting in slower growth rates, fewer regenerative shoots produced, and a compromised photosynthetic system as inferred from fluorescence parameters. CONCLUSIONS For the first time, a desert moss is shown to exhibit an ecological strategy of desiccation tolerance that is inducible, challenging the assumption that arid-land bryophytes rely exclusively on constitutive protection. Results indicate that previous considerations defining a slow-dry event in bryophytes need reevaluation, and that the ecological strategy of inducible desiccation tolerance is probably more common than currently understood among terrestrial bryophytes.
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Affiliation(s)
- Lloyd R Stark
- School of Life Sciences, University of Nevada, 4505 Maryland Parkway, Las Vegas, Nevada 89154-4004, USA.
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Rosenstiel TN, Shortlidge EE, Melnychenko AN, Pankow JF, Eppley SM. Sex-specific volatile compounds influence microarthropod-mediated fertilization of moss. Nature 2012; 489:431-3. [PMID: 22810584 DOI: 10.1038/nature11330] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2012] [Accepted: 06/15/2012] [Indexed: 11/09/2022]
Abstract
Sexual reproduction in non-vascular plants requires unicellular free-motile sperm to travel from male to female reproductive structures across the terrestrial landscape. Recent data suggest that microarthropods can disperse sperm in mosses. However, little is known about the chemical communication, if any, that is involved in this interaction or the relative importance of microarthropod dispersal compared to abiotic dispersal agents in mosses. Here we show that tissues of the cosmopolitan moss Ceratodon purpureus emit complex volatile scents, similar in chemical diversity to those described in pollination mutualisms between flowering plants and insects, that the chemical composition of C. purpureus volatiles are sex-specific, and that moss-dwelling microarthropods are differentially attracted to these sex-specific moss volatile cues. Furthermore, using experimental microcosms, we show that microarthropods significantly increase moss fertilization rates, even in the presence of water spray, highlighting the important role of microarthropod dispersal in contributing to moss mating success. Taken together, our results indicate the presence of a scent-based 'plant-pollinator-like' relationship that has evolved between two of Earth's most ancient terrestrial lineages, mosses and microarthropods.
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Affiliation(s)
- Todd N Rosenstiel
- Department of Biology and Center for Life in Extreme Environments, Portland State University, 1719 SW 10th Avenue, Portland, Oregon 97201, USA
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