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  1 / 31 MEDLINE  
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PMID:27421907
Author:Tomei EJ; Wolniak SM
Address:Department of Cell Biology and Molecular Genetics, University of Maryland at College Park, College Park, MD, 20742, USA.
Title:Kinesin-2 and kinesin-9 have atypical functions during ciliogenesis in the male gametophyte of Marsilea vestita.
Source:BMC Cell Biol; 17(1):29, 2016 Jul 16.
ISSN:1471-2121
Country of publication:England
Language:eng
Abstract:BACKGROUND: Spermatogenesis in the semi-aquatic fern, Marsilea vestita, is a rapid, synchronous process that is initiated when dry microspores are placed in water. Development is post-transcriptionally driven and can be divided into two phases. The first phase consists of nine mitotic division cycles that produce 7 sterile cells and 32 spermatids. During the second phase, each spermatid differentiates into a corkscrew-shaped motile spermatozoid with ~140 cilia. RESULTS: Analysis of the transcriptome from the male gametophyte of Marsilea revealed that one kinesin-2 (MvKinesin-2) and two kinesin-9 s (MvKinesin-9A and MvKinesin-9B) are present during spermatid differentiation and ciliogenesis. RNAi knockdowns show that MvKinesin-2 is required for mitosis and cytokinesis in spermatogenous cells. Without MvKinesin-2, most spermatozoids contain two or more coiled microtubule ribbons with attached cilia and very large cell bodies. MvKinesin-9A is required for the correct placement of basal bodies along the organelle coil. Knockdowns of MvKinesin-9A have basal bodies and cilia that are irregularly positioned. Spermatozoid swimming behavior in MvKinesin-2 and -9A knockdowns is altered because of defects in axonemal placement or ciliogenesis. MvKinesin-2 knockdowns only quiver in place while MvKinesin-9A knockdowns swim erratically compared to controls. In contrast, spermatozoids produced after the silencing of MvKinesin-9B exhibit normal morphology and swimming behavior, though development is slower than normal for these gametes. CONCLUSIONS: Our results show that MvKinesin-2 and MvKinesin-9A are required for ciliogenesis and motility in the Marsilea male gametophyte; however, these kinesins display atypical roles during these processes. MvKinesin-2 is required for cytokinesis, a role not typically associated with this protein, as well as for ciliogenesis during rapid development and MvKinesin-9A is needed for the correct orientation of basal bodies. Our results are the first to investigate the kinesin-linked mechanisms that regulate ciliogenesis in a land plant.
Publication type:JOURNAL ARTICLE
Name of substance:0 (Plant Proteins); EC 3.6.4.4 (Kinesin)


  2 / 31 MEDLINE  
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PMID:26887361
Author:Tomei EJ; Wolniak SM
Address:Department of Cell Biology and Molecular Genetics, University of Maryland at College Park, College Park, Maryland.
Title:Transcriptome analysis reveals a diverse family of kinesins essential for spermatogenesis in the fern Marsilea.
Source:Cytoskeleton (Hoboken); 73(3):145-59, 2016 Mar.
ISSN:1949-3592
Country of publication:United States
Language:eng
Abstract:The male gametophyte of the semi-aquatic fern, Marsilea vestita, produces multiciliated spermatozoids in a rapid developmental sequence that is controlled post-transcriptionally when dry microspores are placed in water. Development can be divided into two phases, mitosis and differentiation. During the mitotic phase, a series of nine successive division cycles produce 7 sterile cells and 32 spermatids in 4.5-5 h. During the next 5-6 h, each spermatid differentiates into a corkscrew-shaped motile spermatozoid with ∼140 cilia. In order to study the mechanisms that regulate spermatogenesis, we used RNAseq to generate a reference transcriptome that allowed us to assess abundance of transcripts at different stages of development. Here, we characterize transcripts present in the kinesin motor family. Over 120 kinesin-like sequences were identified in our transcriptome that represent 56 unique kinesin transcripts. Members of the kinesin-2, -4, -5, -7, -8, -9, -12, -13, and -14 families, in addition to several plant specific and 'orphan' kinesins are present. Most (91%) of these kinesin transcripts change in abundance throughout gametophyte development, with 52% of kinesin mRNAs enriched during the mitotic phase and 39% enriched during differentiation. Functional analyses of six kinesins with different patterns of transcript abundance show that the temporal regulation of these transcripts during gametogenesis correlates directly with kinesin protein function.
Publication type:JOURNAL ARTICLE; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.
Name of substance:0 (Plant Proteins); EC 3.6.4.4 (Kinesin)


  3 / 31 MEDLINE  
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PMID:26222269
Author:Zhang Y; Tian HY; Tan YF; Wong YL; Wu HY; Jia JF; Wang GE; Gao JJ; Li YF; Kurihara H; Shaw PC; Jiang RW
Address:a College of Pharmacy, Jinan University , Guangzhou 510632 , P.R. China.
Title:Isolation and identification of polyphenols from Marsilea quadrifolia with antioxidant properties in vitro and in vivo.
Source:Nat Prod Res; 30(12):1404-10, 2016 Jun.
ISSN:1478-6427
Country of publication:England
Language:eng
Abstract:Marsilea quadrifolia is an edible aquatic medicinal plant used as a traditional health food in Asia. Four new polyphenols including kaempferol 3-O-(2″-O-E-caffeoyl)-ß-d-glucopyranoside (1), kaempferol 3-O-(3″-O-E-caffeoyl)-α-l-arabinopyranoside (3), 4-methy-3'-hydroxypsilotinin (4) and (±)-(E)-4b-methoxy-3b,5b-dihydroxyscirpusin A (18) together with 14 known ones (2, 5-17) were isolated from the ethanol extract of M. quadrifolia. Structures of the new compounds were elucidated by extensive spectroscopic analyses. In DPPH and oxygen radical absorbance capacity antioxidant assays, some compounds showed stronger antioxidant activities and quercetin (9) was the most potent antioxidant in both assays. In a restraint-induced oxidative stress model in mice, quercetin significantly attenuated the increase in plasma ALT and AST levels as well as liver MDA content of restrained mice. Liver SOD activity was also significantly increased by quercetin, indicating a significant in vivo antioxidant activity. As a rich source of polyphenols with strong antioxidant activities, M. quadrifolia may be developed to a product for relieving oxidative stress.
Publication type:JOURNAL ARTICLE
Name of substance:0 (Antioxidants); 0 (Plant Extracts); 0 (Polyphenols); 3K9958V90M (Ethanol); 4Y8F71G49Q (Malondialdehyde); 9IKM0I5T1E (Quercetin)


  4 / 31 MEDLINE  
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PMID:26132035
Author:Cassanego MB; Silveira T; Droste A
Address:Programa de Pós-Graduação em Qualidade Ambiental, Universidade Feevale, Novo Hamburgo, RS, Brazil.
Title:Lead tolerance and accumulation in initial sporophytes of Regnellidium diphyllum Lindm. (Marsileaceae).
Source:Braz J Biol; 75(2):477-83, 2015 May.
ISSN:1678-4375
Country of publication:Brazil
Language:eng
Abstract:Regnellidium diphyllum Lindm. is a heterosporous fern which grows in shallow waters and wetlands, and water pollution contributes to its vulnerability. Environmental lead contamination is mostly caused by industrial and agricultural residues as well as domestic sewage. Given its persistence in the environment, lead can cause important toxicity in living organisms. Megaspore germination and the initial growth of R. diphyllum sporophytes were assessed in Meyer's solution with lead nitrate (Pb(NO3)2) concentrations of 0 (control), 1, 5, 10 and 50 mg L(-1). The study was conducted in a growth chamber at 25 ± 1°C and a 12 hour photoperiod with a nominal irradiance of 100 µmol m(-2) s(-1), for 28 days. Lead concentration in sporophytes was assessed using atomic absorption spectrometry. In the absence of lead, 74% of spores germinated, while significantly lower germination percentages were observed in Pb(NO3)2 concentrations of 1, 10 and 50 mg L(-1). The presence of lead did not significantly influence root growth. At 28 days, primary leaf development was significantly lower in Pb(NO3)2 concentrations of 5 mg L(-1) and higher in relation to the control. The length of secondary leaves did not significantly differ between sporophytes exposed to different concentrations of lead and those of the control at 28 days. Sporophytes exposed to 10 and 50 mg L(-1) Pb(NO3)2 accumulated 1129 mg kg(-1) and 5145 mg kg(-1) of Pb, respectively. The presence of high levels of lead in R. diphyllum sporophytes did not prevent initial development. Future studies should investigate the ability of the species to accumulate and tolerate high levels of lead in advanced stages of its development and in environmental conditions.
Publication type:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
Name of substance:2P299V784P (Lead)


  5 / 31 MEDLINE  
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PMID:26117530
Author:Snehunsu A; Ghosal C; Kandwal M; Yadav PK; Nayak BS; Rao KR; Kamath SU; Sahoo P; Srinivasan KK; Naduvil Narayanan S; Kumar S; Joseph A
Address:Department of Physiology, Kasturba Medical College, Manipal University, Manipal, India.
Title:1-Triacontanol cerotate; isolated from Marsilea quadrifolia Linn. ameliorates reactive oxidative damage in the frontal cortex and hippocampus of chronic epileptic rats.
Source:J Ethnopharmacol; 172:80-4, 2015 Aug 22.
ISSN:1872-7573
Country of publication:Ireland
Language:eng
Abstract:ETHNOPHARMACOLOGICAL RELEVANCE: Marsilea quadrifolia Linn. (MQ) has been used for insomnia and epileptic disorders in traditional Indian medicine. The present study is to isolate the active component responsible for antiepileptic property of MQ by evaluating its ability to minimize the reactive oxidative damage in brain due to chronic epilepsy in rat. MATERIALS AND METHODS: 1-Triacontanol cerotate (1TAC) was isolated after chromatography on a silica gel from dried petroleum ether fraction of methanolic extract of MQ. Acute oral toxicity studies of 1TAC were carried out and efficacy of 1TAC on malondialdehyde (MDA) and reduced glutathione (GSH) production in different brain areas of chronic pentylenetetrazole (PTZ) induced epileptic rats were evaluated. RESULTS: Our results showed that PTZ-kindled chronic epileptic rats had an increase MDA and decreased GSH concentration in the frontal cortex as well as hippocampus, compared to the normal control. MDA and GSH concentrations in those brain areas were normalized after treatment with sodium valproate (SV) in 200 mg kg(-1)bw; as well as 1TAC in 40 and 80 mg kg(-1)bw doses. CONCLUSION: Production of reactive oxygen species (ROS) is known to worsen epileptogenesis. The isolated component 1TAC which reduced the reactive oxidative damage in hippocampus and frontal cortex of PTZ kindled rats could be responsible for antiepileptic property of MQ. Its action is found to be dose dependent, with 80 mg kg(-1)bw showing even better efficacy than 200 mg kg(-1)bw of SV.
Publication type:JOURNAL ARTICLE
Name of substance:0 (Fatty Alcohols); 4Y8F71G49Q (Malondialdehyde); 614OI1Z5WI (Valproic Acid); 767RD0E90B (1-triacontanol); GAN16C9B8O (Glutathione); WM5Z385K7T (Pentylenetetrazole)


  6 / 31 MEDLINE  
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PMID:25837402
Author:Wolniak SM; Boothby TC; van der Weele CM
Address:Department of Cell Biology and Molecular Genetics, University of Maryland, College Park MD 20742, USA.
Title:Posttranscriptional control over rapid development and ciliogenesis in Marsilea.
Source:Methods Cell Biol; 127:403-44, 2015.
ISSN:0091-679X
Country of publication:United States
Language:eng
Abstract:Marsilea vestita is a semiaquatic fern that produces its spores (meiotic products) as it undergoes a process of natural desiccation. During the period of desiccation, the spores mature, and produce large quantities of pre-mRNA, which is partially processed and stored in nuclear speckles and can remain stable during a period of extended quiescence in the dry spore. Rehydration of the spores initiates a highly coordinated developmental program, featuring nine successive mitotic division cycles that occur at precise times and in precise planes within the spore wall to produce 39 cells, 32 of which are spermatids. The spermatids then undergo de novo basal body formation, the assembly of a massive cytoskeleton, nuclear and cell elongation, and finally ciliogenesis, before being released from the spore wall. The entire developmental program requires only 11 h to reach completion, and is synchronous in a population of spores rehydrated at the same time. Rapid development in this endosporic gametophyte is controlled posttranscriptionally, where stored pre-mRNAs, many of which are intron-retaining transcripts, are unmasked, processed, and translated under tight spatial and temporal control. Here, we describe posttranscriptional mechanisms that exert temporal and spatial control over this developmental program, which culminates in the production of ∼140 ciliary axonemes in each spermatozoid.
Publication type:JOURNAL ARTICLE; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.
Name of substance:0 (Plant Proteins); 0 (RNA, Messenger); 0 (RNA, Plant); 0 (RNA, Small Interfering); U87FK77H25 (Spermidine)


  7 / 31 MEDLINE  
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PMID:25273473
Author:Wu HL; Sheng YJ; Tsao HK
Address:Department of Chemical Engineering, National Taiwan University, Taipei 106, Taiwan.
Title:Phase behaviors and membrane properties of model liposomes: temperature effect.
Source:J Chem Phys; 141(12):124906, 2014 Sep 28.
ISSN:1089-7690
Country of publication:United States
Language:eng
Abstract:The phase behaviors and membrane properties of small unilamellar vesicles have been explored at different temperatures by dissipative particle dynamics simulations. The vesicles spontaneously formed by model lipids exhibit pre-transition from gel to ripple phase and main transition from ripple to liquid phase. The vesicle shape exhibits the faceted feature at low temperature, becomes more sphere-like with increasing temperature, but loses its sphericity at high temperature. As the temperature rises, the vesicle size grows but the membrane thickness declines. The main transition (Tm) can be identified by the inflection point. The membrane structural characteristics are analyzed. The inner and outer leaflets are asymmetric. The length of the lipid tail and area density of the lipid head in both leaflets decrease with increasing temperature. However, the mean lipid volume grows at low temperature but declines at high temperature. The membrane mechanical properties are also investigated. The water permeability grows exponentially with increasing T but the membrane tension peaks at Tm. Both the bending and stretching moduli have their minima near Tm. Those results are consistent with the experimental observations, indicating that the main signatures associated with phase transition are clearly observed in small unilamellar vesicles.
Publication type:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
Name of substance:0 (Gels); 0 (Lipid Bilayers); 0 (Liposomes)


  8 / 31 MEDLINE  
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PMID:24215095
Author:Snehunsu A; Mukunda N; Satish Kumar MC; Sadhana N; Naduvil Narayanan S; Vijay Kapgal K; Avinash H; Chandrashekar BR; Raghavendra Rao K; Nayak BS
Address:Department of Physiology, Kasturba Medical College, Manipal University , Manipal , India .
Title:Evaluation of anti-epileptic property of Marsilea quadrifolia Linn. in maximal electroshock and pentylenetetrazole-induced rat models of epilepsy.
Source:Brain Inj; 27(13-14):1707-14, 2013.
ISSN:1362-301X
Country of publication:England
Language:eng
Abstract:OBJECTIVE: To study the anti-epileptic effects of methanolic extract of Marsilea quadrifolia Linn. (MQ) in maximal electroshock (MES) and pentylenetetrazole (PTZ) induced rat models of epilepsy. METHOD: A total of 84 adult male Wistar rats were used. An acute oral toxicity study was conducted on 36 rats and the remaining were used for other experiments. Each model had 24 rats which were allotted into four groups (n = 6). Group I (Control) received 1% carboxymethyl cellulose solution, Group II (Positive control) received phenytoin 300 mg kg(-1) b.w. in the MES model; sodium valproate 200 mg kg(-1) b.w. in the PTZ model, Group III (MQ) received 400 mg kg(-1) b.w. MQ extract and Group IV (MQ) received 600 mg kg(-1) b.w. MQ extract. Hind limb extension (HLE) time and recovery time were noted in the MES model. Latency for myoclonic jerk, seizures and EEG was recorded in the PTZ model. RESULTS: When compared to control, the phenytoin received group did not show HLE. In MQ pre-treated groups only 50% of rats showed HLE. Sodium valproate and various doses of MQ significantly increased the latency for onset of clonus and seizures. PTZ-induced EEG alterations were significantly attenuated by MQ administration and this was comparable to that of the sodium valproate effect. CONCLUSION: Marsilea quadrifolia Linn. showed significant anti-epileptic efficacy against various epilepsy models.
Publication type:JOURNAL ARTICLE
Name of substance:0 (Convulsants); 0 (Plant Preparations); 614OI1Z5WI (Valproic Acid); WM5Z385K7T (Pentylenetetrazole)


  9 / 31 MEDLINE  
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PMID:23857737
Author:Chau MM; Reyes WR; Ranker TA
Address:Department of Botany, University of Hawai'i at Manoa, Honolulu, Hawai'i 96822, USA. mmchau@hawaii.edu
Title:Ecological factors influencing growth of the endangered Hawaiian fern Marsilea villosa (Marsileaceae) and implications for conservation management.
Source:Am J Bot; 100(8):1532-43, 2013 Aug.
ISSN:1537-2197
Country of publication:United States
Language:eng
Abstract:PREMISE OF THE STUDY: Conserving endangered plants is a complex task, and practitioners must often use a "triage" approach, addressing only immediate needs. Ecologists can improve this process by conducting sound science upon which to base management. Marsilea villosa is an endangered, endemic Hawaiian fern with seven remaining populations in ephemerally flooding drylands. Among its uncommon traits are long-lived sporocarps, requiring flood and drought to complete its sexual life cycle, and extensive vegetative growth. METHODS: We conducted a 3-yr ecological field study, measuring percent cover of M. villosa and associated species, flooding depth, and canopy cover, to identify ecological factors with the greatest impact on M. villosa growth. KEY RESULTS: Maximum flooding depth and canopy cover had strong positive relationships with M. villosa growth, and all plots with >50% threshold of either variable reached 100% cover of M. villosa by the end of the study. Interaction effects explained nuances of these relationships, including synergy between the two variables. Percent cover of nonnative functional groups (graminoids and nongraminoids) each had negative relationships with M. villosa growth, but interactions showed that nongraminoid cover was driven by particular species, and that time since flooding had greater influence on M. villosa growth than graminoid cover. CONCLUSIONS: We recommend planting reintroduced populations in flood-prone areas with moderate shade, experimental outplanting of native plants with M. villosa, and management of graminoids as a functional group, while nongraminoid management should be species-specific. These practices will promote self-sustaining populations and reduce the need for labor-intensive management.
Publication type:JOURNAL ARTICLE; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.


  10 / 31 MEDLINE  
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PMID:23821521
Author:Gao L; Wang B; Wang ZW; Zhou Y; Su YJ; Wang T
Address:CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China.
Title:Plastome sequences of Lygodium japonicum and Marsilea crenata reveal the genome organization transformation from basal ferns to core leptosporangiates.
Source:Genome Biol Evol; 5(7):1403-7, 2013.
ISSN:1759-6653
Country of publication:England
Language:eng
Abstract:Previous studies have shown that core leptosporangiates, the most species-rich group of extant ferns (monilophytes), have a distinct plastid genome (plastome) organization pattern from basal fern lineages. However, the details of genome structure transformation from ancestral ferns to core leptosporangiates remain unclear because of limited plastome data available. Here, we have determined the complete chloroplast genome sequences of Lygodium japonicum (Lygodiaceae), a member of schizaeoid ferns (Schizaeales), and Marsilea crenata (Marsileaceae), a representative of heterosporous ferns (Salviniales). The two species represent the sister and the basal lineages of core leptosporangiates, respectively, for which the plastome sequences are currently unavailable. Comparative genomic analysis of all sequenced fern plastomes reveals that the gene order of L. japonicum plastome occupies an intermediate position between that of basal ferns and core leptosporangiates. The two exons of the fern ndhB gene have a unique pattern of intragenic copy number variances. Specifically, the substitution rate heterogeneity between the two exons is congruent with their copy number changes, confirming the constraint role that inverted repeats may play on the substitution rate of chloroplast gene sequences.
Publication type:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
Name of substance:0 (Plant Proteins)



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