A Persisting Cellulosic Wall of Microspore Mother Cells during Microsporogenesis in Allium tuberosum Rottl. and Cyclamen persicum Mill

Nine-week-old plants of Cyclamen persicum `Miracle Salmon' were transplanted into 10-cm pots and placed in growth chambers at 8, 12, 16, 20, or 24 °C. The irradiance was 10 mol/day per m2 during a 16-h day length. After 8 weeks, the temperature was changed to 16 °C for all plants. Expanded leaves (1 cm or larger) were counted at weekly intervals for each plant. The rate of leaf unfolding increased with temperature to 20 °C. The fastest rate at 20 °C was 0.34 ± 0.05 leaf/day. Flower buds were visible 55 ± 7 days from start of temperature treatments (118 days from seeding) for the plants grown at 12, 16, or 20 °C. Flower buds appeared 60 ± 6.9 days from initiation of treatments for plants grown at 24 °C and 93 ± 8.9 days for cyclamens grown at 8 °C. Although there was no significant difference in rate of flower bud appearance for cyclamens grown at 12, 16, or 20 °C, the number of leaves, flowers, and flower buds varied significantly among all temperature treatments. Leaf number at flowering increased from 38 ± 4.7 for plants at 12 °C to 77 ± 8.3 at 24 °C. Flowers and flower buds increased from 18 ± 2.9 to 52 ± 11.0 as temperature increased from 12 to 24 °C. Plants grown at 8 °C had on average 6 ± 2 visible flower buds, but no open flowers at termination of the study (128 days from start of treatments).

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Chromosome Behavior During Meiosis in the Pollen Mother Cells of Certain Oenotheras

The American Naturalist ◽

10.1086/280059 ◽

1925 ◽

Vol 59 (664) ◽

pp. 475-479 ◽

Cited By ~ 17

Author(s):

Ralph E. Cleland

Keyword(s):

Chromosome Behavior ◽

Pollen Mother Cells ◽

Mother Cells

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C-banding and fluorescence in situ hybridization studies of the wheat–alien hybrid 'Agrotana'

Genome ◽

10.1139/g94-066 ◽

1994 ◽

Vol 37 (3) ◽

pp. 477-481 ◽

Cited By ~ 13

Author(s):

Jie Xu ◽

R. L. Conner ◽

A. Laroche

Keyword(s):

In Situ Hybridization ◽

Fluorescence In Situ Hybridization ◽

Genomic Dna ◽

Chromosome Engineering ◽

C Banding ◽

Chinese Spring Wheat ◽

Mother Cells ◽

Alien Chromatin ◽

Chromosome Segments

'Agrotana', a wheat-alien hybrid (2n = 56), is a potential source of resistance to common root rot, stem rust, wheat streak mosaic virus, and the wheat curl mite. However, the origin of 'Agrotana', reported to be durum wheat × Agropyron trichophorum (pubescent wheatgrass), is uncertain. The objective of this investigation was to determine the chromosome constitution of 'Agrotana' using C-banding and fluorescence in situ hybridization techniques. The F1 hybrid of 'Agrotana' × 'Chinese Spring' wheat showed 7 I + 21 II in 14.9% of the pollen mother cells, evidence of the presence of the A, B, and D genomes in 'Agrotana'. The hybrid had 16 heavily C-banded chromosomes, namely 4A, and 1-7B of wheat, and a translocation that probably involved wheat chromosomes 2A and 2D. In situ hybridization using biotinylated genomic DNA of Ag. trichophorum cv. Greenleaf blocked with CS DNA failed to identify the alien chromosomes in 'Agrotana', indicating that the alien chromosomes were not likely derived from pubescent wheatgrass. In situ hybridization using labelled wheat genomic DNA blocked with 'Agrotana' DNA revealed that 'Agrotana' had 40 wheat, 14 alien, and 2 (a pair) wheat–alien translocated chromosomes. There was no homology between wheat and the alien chromosomes or chromosome segments involved in the wheat–alien recombinant. Two of the seven pairs of alien chromosomes were homoeologous to each other. The ability to identify alien chromatin in wheat using labelled wheat DNA instead of labelled alien DNA will be particularly useful in chromosome engineering of wheat germplasms having alien chromatin of unknown origin.Key words: wheat–alien hybrid, C-banding, fluorescence in situ hybridization, labelled wheat DNA as probe.

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Male meiosis and pollen morphology in diploid Indonesian wild bananas and cultivars

The Nucleus ◽

10.1007/s13237-021-00350-7 ◽

2021 ◽

Author(s):

Fajarudin Ahmad ◽

Yuyu S. Poerba ◽

Gert H. J. Kema ◽

Hans de Jong

Keyword(s):

Hybrid Sterility ◽

Pollen Grains ◽

Chromosome Analysis ◽

Male Meiosis ◽

Enzyme Treatment ◽

Unreduced Gamete ◽

Ploidy Levels ◽

Scientific Disciplines ◽

Sterile Pollen ◽

Mother Cells

AbstractBreeding of banana is hampered by its genetic complexity, structural chromosome rearrangements and different ploidy levels. Various scientific disciplines, including cytogenetics, linkage mapping, and bioinformatics, are helpful tools in characterising cultivars and wild relatives used in crossing programs. Chromosome analysis still plays a pivotal role in studying hybrid sterility and structural and numerical variants. In this study, we describe the optimisation of the chromosome spreading protocol of pollen mother cells focusing on the effects of standard fixation methods, duration of the pectolytic enzyme treatment and advantages of fluorescence microscopy of DAPI stained cell spreads. We demonstrate the benefits of this protocol on meiotic features of five wild diploid Musa acuminata bananas and a diploid (AA) cultivar banana “Rejang”, with particular attention on pairing configurations and chromosome transmission that may be indicative for translocations and inversions. Pollen slides demonstrate regular-shaped spores except “Rejang”, which shows fertile pollen grains of different size and sterile pollen grains, suggesting partial sterility and unreduced gamete formation that likely resulted from restitutional meiotic divisions.

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Effect of Chinese chives (Allium tuberosum) addition to carboxymethyl cellulose based food packaging films

Carbohydrate Polymers ◽

10.1016/j.carbpol.2020.115944 ◽

2020 ◽

Vol 235 ◽

pp. 115944 ◽

Cited By ~ 1

Author(s):

Asad Riaz ◽

Camel Lagnika ◽

Hao Luo ◽

Meimei Nie ◽

Zhuqing Dai ◽

...

Keyword(s):

Carboxymethyl Cellulose ◽

Food Packaging ◽

Packaging Films ◽

Allium Tuberosum ◽

Food Packaging Films ◽

Chinese Chives

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A Role for the Actin Cytoskeleton of Saccharomyces cerevisiae in Bipolar Bud-Site Selection

The Journal of Cell Biology ◽

10.1083/jcb.136.1.111 ◽

1997 ◽

Vol 136 (1) ◽

pp. 111-123 ◽

Cited By ~ 58

Author(s):

Shirley Yang ◽

Kathryn R. Ayscough ◽

David G. Drubin

Keyword(s):

Saccharomyces Cerevisiae ◽

Actin Cytoskeleton ◽

Site Selection ◽

Mitotic Checkpoint ◽

Cell Cortex ◽

Spatial Cues ◽

Genes Encoding ◽

Mother And Daughter ◽

Mother Cells ◽

Bud Site

Saccharomyces cerevisiae cells select bud sites according to one of two predetermined patterns. MATa and MATα cells bud in an axial pattern, and MATa/α cells bud in a bipolar pattern. These budding patterns are thought to depend on the placement of spatial cues at specific sites in the cell cortex. Because cytoskeletal elements play a role in organizing the cytoplasm and establishing distinct plasma membrane domains, they are well suited for positioning bud-site selection cues. Indeed, the septin-containing neck filaments are crucial for establishing the axial budding pattern characteristic of MATa and MATα cells. In this study, we determined the budding patterns of cells carrying mutations in the actin gene or in genes encoding actin-associated proteins: MATa/α cells were defective in the bipolar budding pattern, but MATa and MATα cells still exhibit a normal axial budding pattern. We also observed that MATa/α actin cytoskeleton mutant daughter cells correctly position their first bud at the distal pole of the cell, but mother cells position their buds randomly. The actin cytoskeleton therefore functions in generation of the bipolar budding pattern and is required specifically for proper selection of bud sites in mother MATa/α cells. These observations and the results of double mutant studies support the conclusion that different rules govern bud-site selection in mother and daughter MATa/α cells. A defective bipolar budding pattern did not preclude an sla2-6 mutant from undergoing pseudohyphal growth, highlighting the central role of daughter cell bud-site selection cues in the formation of pseudohyphae. Finally, by examining the budding patterns of mad2-1 mitotic checkpoint mutants treated with benomyl to depolymerize their microtubules, we confirmed and extended previous evidence indicating that microtubules do not function in axial or bipolar bud-site selection.

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Early Adhesion of Candida albicans onto Dental Acrylic Surfaces

Journal of Dental Research ◽

10.1177/0022034517706354 ◽

2017 ◽

Vol 96 (8) ◽

pp. 917-923 ◽

Cited By ~ 12

Author(s):

S. Aguayo ◽

H. Marshall ◽

J. Pratten ◽

D. Bradshaw ◽

J.S. Brown ◽

...

Keyword(s):

Candida Albicans ◽

Clinical Isolate ◽

Force Spectroscopy ◽

Laboratory Strain ◽

Culture Conditions ◽

The Body ◽

Yeast Cells ◽

Adhesion Forces ◽

Reliable Technique ◽

Mother Cells

Denture-associated stomatitis is a common candidal infection that may give rise to painful oral symptoms, as well as be a reservoir for infection at other sites of the body. As poly (methyl methacrylate) (PMMA) remains the main material employed in the fabrication of dentures, the aim of this research was to evaluate the adhesion of Candida albicans cells onto PMMA surfaces by employing an atomic force microscopy (AFM) single-cell force spectroscopy (SCFS) technique. For experiments, tipless AFM cantilevers were functionalized with PMMA microspheres and probed against C. albicans cells immobilized onto biopolymer-coated substrates. Both a laboratory strain and a clinical isolate of C. albicans were used for SCFS experiments. Scanning electron microscopy (SEM) and AFM imaging of C. albicans confirmed the polymorphic behavior of both strains, which was dependent on growth culture conditions. AFM force-spectroscopy results showed that the adhesion of C. albicans to PMMA is morphology dependent, as hyphal tubes had increased adhesion compared with yeast cells ( P < 0.05). C. albicans budding mother cells were found to be nonadherent, which contrasts with the increased adhesion observed in the tube region. Comparison between strains demonstrated increased adhesion forces for a clinical isolate compared with the lab strain. The clinical isolate also had increased survival in blood and reduced sensitivity to complement opsonization, providing additional evidence of strain-dependent differences in Candida-host interactions that may affect virulence. In conclusion, PMMA-modified AFM probes have shown to be a reliable technique to characterize the adhesion of C. albicans to acrylic surfaces.

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