by Goodfellow J., Eamus D., Duff G. (1997)
John Goodfellow, Derek Eamus, G. Duff
School of Biological Sciences, Northern Territory University, Darwin, NT 0909, Australia
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in Tree Physiology 17: 291-299 –
by Ghannoum O., Conroy J. P. Driscoll S. P., Paul M. J., Foyer C. H., Lawlor D. W. (2003)
in New Phytologist 159: 599–608 – https://doi.org/10.1046/j.1469-8137.2003.00835.x –
https://nph.onlinelibrary.wiley.com/doi/full/10.1046/j.1469-8137.2003.00835.x
Summary
by Gautier H., Vavasseur A., Gans P,. Lasceve G. (1991)
Hélène Gautier, Alain Vavasseur, Pierre Gans, Gérard Lascève,
Département de Physiologie Végétale et Ecosystèmes, Centre d’Etudes Nucléaires de Cadarache, F-13108 Saint-Paul-lez-Durance, Cedex, France.
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in Plant Physiol. 95: 636–641 – PMID: 16668030 – PMCID: PMC1077579 –
https://www.ncbi.nlm.nih.gov/pubmed/16668030
Abstract
A mass spectrometric method combining (16)O/(18)O and (12)C/(13)C isotopes was used to quantify the unidirectional fluxes of O(2) and CO(2) during a dark to light transition for guard cell protoplasts and mesophyll cell protoplasts of Commelina communis L.
In darkness, O(2) uptake and CO(2) evolution were similar on a protein basis. Under light, guard cell protoplasts evolved O(2) (61 micromoles of O(2) per milligram of chlorophyll per hour) almost at the same rate as mesophyll cell protoplasts (73 micromoles of O(2) per milligram of chlorophyll per hour). However, carbon assimilation was totally different. In contrast with mesophyll cell protoplasts, guard cell protoplasts were able to fix CO(2) in darkness at a rate of 27 micromoles of CO(2) per milligram of chlorophyll per hour, which was increased by 50% in light.
At the onset of light, a delay observed for guard cell protoplasts between O(2) evolution and CO(2) fixation and a time lag before the rate of saturation suggested a carbon metabolism based on phosphoenolpyruvate carboxylase activity.
Under light, CO(2) evolution by guard cell protoplasts was sharply decreased (37%), while O(2) uptake was slowly inhibited (14%). A control of mitochondrial activity by guard cell chloroplasts under light via redox equivalents and ATP transfer in the cytosol is discussed.
From this study on protoplasts, we conclude that the energy produced at the chloroplast level under light is not totally used for CO(2) assimilation and may be dissipated for other purposes such as ion uptake.
by Galbiati M., Matus J. T., Francia P., Rusconi F., Cañón P., Medina C., Conti L., Cominelli E., Tonelli C., Arce-Johnson P. (2011)
Dipartimento di Scienze Biomolecolari e Biotecnologie, Università degli Studi di Milano, Via Celoria 26, 20133 Milano, Italy.
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in BMC Plant Biology 11:142 – https://doi.org/10.1186/1471-2229-11-142 –
https://bmcplantbiol.biomedcentral.com/articles/10.1186/1471-2229-11-142
Abstract
Background
Under drought, plants accumulate the signaling hormone abscisic acid (ABA), which induces the rapid closure of stomatal pores to prevent water loss. This event is trigged by a series of signals produced inside guard cells which finally reduce their turgor. Many of these events are tightly regulated at the transcriptional level, including the control exerted by MYB proteins. In a previous study, while identifying the grapevine R2R3 MYB family, two closely related genes, VvMYB30 and VvMYB60 were found with high similarity to AtMYB60, an Arabidopsis guard cell-related drought responsive gene.
Results
Promoter-GUS transcriptional fusion assays showed that expression of VvMYB60 was restricted to stomatal guard cells and was attenuated in response to ABA. Unlike VvMYB30, VvMYB60 was able to complement the loss-of-function atmyb60-1 mutant, indicating that VvMYB60 is the only true ortholog of AtMYB60 in the grape genome. In addition, VvMYB60 was differentially regulated during development of grape organs and in response to ABA and drought-related stress conditions.
Conclusions
These results show that VvMYB60 modulates physiological responses in guard cells, leading to the possibility of engineering stomatal conductance in grapevine, reducing water loss and helping this species to tolerate drought under extreme climatic conditions.
by Galatis B., Apostolakos P., Katsaros C. (1983)
Institute of General Botany, University of Athens, Athens, Greece
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in Protoplasma 117: 24–39 – https://doi.org/10.1007/BF01281781 –
https://link.springer.com/article/10.1007%2FBF01281781
Summary
In the primary leaves of three Triticum species examined, two successive guard cell mother cells (GMCs) are often laterally flanked by one epidermal cell which is induced twice by them and forms two subsidiary cells (SCs). In the case of simultaneous induction of the common subsidiary cell mother cell (SMC) by the GMCs, its nucleus does not migrate towards either of the GMCs, but occupies a position between them.
Unexpectedly, in a number of the above “double-polarized” SMCs, two preprophase microtubule bands (PMBs) are organized at the same time, apposed on the GMCs at the expected positions. In some of those cells the daughter wall exhibits aberrant dispositions and either a small lens-shaped cell adjacent to the intervening cell between the GMCs or a large SC alongside both the GMCs and the intervening cell, or an SC flanking one GMC and a part of the intervening cell between the GMCs are separated.
Obviously, the sites of fusion of the cell plate with the parent walls do not coincide completely with those of either of the PMB cortical zones. These cell plates appear to intersect those parental walls which are common with the intervening cells at PMB cortical sites belonging to two PMBs. Besides, the one end of the cell plate may pass from the cortical zone of the one PMB to another of the other PMB.
by Fukuda M., Hasezawa S., Nakajima N., Kondo N. (2000)
Megumi Fukuda1 , Seiichiro Hasezawa1 , Nobuyoshi Nakajima3 and Noriaki Kondo 1
1 Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Bunkyo-ku, Tokyo, 113 Japan
2 Department of Biology, The University of Tsukuba, Tsukuba, Ibaraki, 305 Japan
3 Biotechnology Research Team, Division of Regional Environment, National Institute for Environmental Studies, Onogawa 16-2, Tsukuba, 305 Japan
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in Plant Cell Physiology 41: 600–607 –
https://www.ncbi.nlm.nih.gov/pubmed/10929943
We previously reported that the organization of microtubules (MTs) in guard cells of Vicia faba L. shows dynamic diurnal changes [Fukuda et al. (1998) Plant Cell Physiol. 39: 80].
Here, we report a method to directly extract total proteins from guard cells to investigate the biochemical changes in guard cells of Vicia faba L. during the diurnal cycle.
Electrophoretic profiles of total proteins of guard cells showed distinct patterns with the time of extraction. Immunoblot analysis also demonstrated changes in alpha-tubulin and beta-tubulin contents with the diurnal cycle. Both tubulins were abundant at 6:00 h and 12:00 h but were almost undetectable at 24:00 h. Although treatment with either actinomycin D or cycloheximide at 18:00 h inhibited neither radial organization of cortical MTs nor stomatal opening, that at 6:00 h inhibited both.
These results suggest that the dynamic diurnal changes in the organization of MTs in guard cells and stomatal movement of Vicia faba L. may be, at least partly, regulated by de novo synthesis and decomposition of tubulin molecules in guard cells.
Fig. 1 MTs in guard cells of Viciafaba L. at various times of the day, at two focal planes. A-D; cell cortex. E-H; midplane. A, E; guard cells fixed at 12:00 h, termed Radial state. B, F; fixed at 18:00 h, termed Transitional I state. C, G; fixed at 0:00 h, termed Fragmental state. D, H; fixed at 06:00 h, termed Transitional II state. Bar indicates \0/im.
by Fukuda M., Hasezawa S., Asai N., Nakajima N., Kondo N. (1998)
Megumi Fukuda1 , Seiichiro Hasezawa1 , Naoko Asai2 , Nobuyoshi Nakajima3 and Noriaki Kondo 1
1 Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Bunkyo-ku, Tokyo, 113 Japan
2 Department of Biology, The University of Tsukuba, Tsukuba, Ibaraki, 305 Japan
3 Biotechnology Research Team, Division of Regional Environment, National Institute for Environmental Studies, Onogawa 16-2, Tsukuba, 305 Japan
===
in Plant Cell Physiology 39: 80–86 –
https://www.ncbi.nlm.nih.gov/pubmed/9517004
Abstract
Stomatal movement is regulated by changes in the volume of guard cells, thought to be mainly controlled by an osmo-regulatory system.
In the present study, we examined the additional involvement of cytoskeletal events in the regulation of stomatal movement. Microtubules (MTs) in guard cells of Vicia faba L., grown under sunlight, were observed during the day and night by immunofluorescence microscopy. Cortical MTs began to be organized in a radial array at dawn and increased in numbers in the morning following the increase in the stomatal aperture size. Thereafter, MTs became localized near the nucleus and began to be destroyed from the evening to midnight, following the decrease in stomatal aperture size.
These diurnal changes in MT organization were observed even two days after transfer from natural light condition to total darkness, and were accompanied by corresponding changes in stomatal aperture.
The increase in stomatal aperture size in the early morning was inhibited by 50 microM propyzamide, which destroys cortical MTs in guard cells, whereas the decrease in aperture size in the evening was suppressed by 10 microM taxol, which stabilizes cortical MTs.
These results suggest that radially-organized cortical MTs of guard cells may control diurnal stomatal movement.
by Fricker M. D., Willmer C. M. (1990)
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in J. Exp. Bot. 41(2): 193-198 – https://doi.org/10.1093/jxb/41.2.193 –
https://academic.oup.com/jxb/article-abstract/41/2/193/498816?redirectedFrom=fulltext
Abstract
A low level of azide-sensitive ATPase activity was detected with a pH optimum of 6.8. This activity was stimulated by 0.01% (v/v) Triton X-100, and the pH optimum shifted to pH 7.4.
Nitrate-sensitive ATPase activity was measured in the presence of azide and showed a pH optimum around pH 8.0. Proton pumping activity in a mixed population of vesicles from GCP was monitored using fluorescence quenching of quinacrine. Mg-ATP dependent proton pumping was observed at pH 8.0, but not at pH 6.6.
The activity at pH 8.0 was inhibited by nitrate and DCCD but not vanadate.
These data indicate that activity of the tonoplast proton pump was being measured. There was, however, no evidence for a tonoplast cation (K+)/proton antiporter under these assay conditions as potassium did not reduce the initial rate of pH gradient formation or increase the rate of collapse of a pre-formed gradient after inhibition of the pump.
by Wang W., Zhao N.-X. (2002)
| WANG Wei, ZHAO Nan-Xian, |
| South China Institute of Botany, The Chinese Academy of Sciences, Guangzhou 510650, China |
===
in Plant Sci J. 20: 343-349 –
http://www.whzwxyj.cn/EN/abstract/abstract1623.shtml
Abstract
The leaf epidermal structures of 27 species from 18 genera of Araceae and 1 species from Acoraceae were examined under light microscope,14 of which were observed with scanning electron microscope.
The stomatal apparatus types of Araceae vary from anomocytic, actinocytic to paracytic, cyclocytic and transitionary type between paracytic and cyclocytic; the numbers of subsidiary cells from zero to twelve.
Epidermal cells are nearly isodiametric in outline with straight, arched and undulate anticlinal walls.
Striate ornamentation occurs on periclinal walls of epidermal cells in some species. Although the stomatal apparatus types in Araceae are of little taxonomical significance at infra-family level of Araceae, the combined characters of stomatal apparatuses, the shape of anticlinal wall and ornamentation of cuticules in guard cells may be useful for species identification.
The separation of Acorus from Araceae is supported by leaf epidermal structures.
by Mantovani A., Pereira T. E. (2005)
André Mantovani, Instituto de Pesquisas Jardim Botânico do Rio de Janeiro, Programa Zona Costeira, Rua Pacheco Leão 915, CEP 22460-030, Jardim Botânico, Rio de Janeiro, Brasil,
Thaís Estefani Pereira, Bolsista Iniciação Científica PIBIC/CNPq.
===
in Rodriguésia 56 (88): 145-160 –
https://rodriguesia.jbrj.gov.br/FASCICULOS/rodrig56_88/10_Mantovani.pdf
ABSTRACT
Leaf and spathe anatomy of seven species and two varieties of the genus Anthurium (section Urospadix; subsection Flavescentiviridia) were analyzed. Plant material was collected from different locations in Brazil and cultivated under identical glasshouse conditions in the Rio de Janeiro Botanical Garden. Our attempt is to evaluate the diagnostic potential of leaf and spathe anatomy for taxonomic purposes. Leaves presented smooth cuticle, polygonal epidermal cells randomly disposed in paradermal view, periclinal divisions of epidermal cells in transversal view, non-raised stomata, collenchyma, sclerenchymatic bundle sheaths and raphides in the mesophyll. The spathe presented cuticularstriations; rectangular and elongated cellsin parallel rows; raised stomata; absence of collenchyma, raphides and sclerenchymatic bundle sheaths and presence of sclerenchyma as fibre caps under phloem. Clustering analysis based on leaf and spathe anatomical characters, revealed that the spathe can give a better resolution for segregation of species groups.
RESUMO
São apresentados dados relativos à anatomia da lâmina foliar e espata de sete espécies e duas variedades do gênero Anthurium pertencentes à seção Urospadix; subseção Flavescentiviridia. Os indivíduos foram coletados nos estados do Rio de Janeiro, São Paulo e Minas Gerais, e aclimatados no Instituto de Pesquisas Jardim Botânico do Rio de Janeiro. O objetivo deste estudo é comparar anatomicamente lâmina foliar e espata, visando detectar qual das duas estruturas é mais útil à diagnose taxonômica das espécies estudadas. Observa-se nas folhas a presença de cutícula lisa e células epidérmicas dispostas ao acaso, estômatos nivelados com a epiderme, divisões periclinais em células epidérmicas, além de ráfides no mesofilo e bainha esclerenquimática nos feixes vasculares. Já quanto à espata observa-se cutícula estriada, células alongadas e ordenadas de forma paralela, estômatos por vezes elevados, ausência de ráfides e presença de calota de fibras apenas junto ao floema, quando não ausentes. A análise de agrupamento para folha e espata revelou maior poder de resolução com base em caracteres anatômicos da espata; além dos grupos formados com base nos caracteres anatômicos da folha não serem consistentes taxonomicamente. Sugere-se portanto que a espata apresenta maior valor diagnóstico ao nível anatômico para subsidiar estudos taxonômicos do gênero Anthurium.
PLANT STOMATA ENCYCLOPEDIA 
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