ATTEMPTS TO OVERCOME THE BARRIER OF INTERSPECIFIC HYBRIDIZATION BETWEEN CUCUMIS MELO AND C. METULIFERUS

1995 ◽  
Vol 43 (2) ◽  
pp. 113-123 ◽  
Author(s):  
Alexander Beharav ◽  
Yigal Cohen
Keyword(s):  
Gamma Rays ◽  
Cucumis Melo ◽  
Fruit Set ◽  
Normal Development ◽  
Pollen Tubes ◽  
Radiation Doses ◽  
Cross Pollination ◽  
Mentor Pollen

The crossability ofCucumis meloandC. metuliferuswas studied in order to find ways to effect the cross between the two species. In cross-pollination withinC. melo, the pollen tubes entered the ovarian cavity within 24 h, and fertilization occurred within 48 h. Pollen germinated well after cross-pollination between the species, but pollen tubes grew slowly.C. metuliferuspollen tubes were arrested in the stigma or the upper style ofC. meloflowers.The influence of 100-, 150-, and 200-krad gamma radiation on in vitro germination, pollen tube growth ofC. meloandC. metuliferus, and on in vivo fertilization ofC. melowas studied. Pollen ofC. metuliferusappeared to be much less sensitive to gamma rays than that ofC. melo.Higher radiation doses were found to reduce fruit set ofC. melo.Irradiation of pollen ofC. meloalways resulted in “pseudo-fertilization”.We attempted to overcome the prefertilization crossing barrier betweenC. meloandC. metuliferusby using techniques of bud pollination, benzyladenine (BA) treatment, and irradiated mentor pollen. Ten lines ofC. meloand 6 accessions ofC. metuliferuswere used as female and male parents, respectively. The techniques of BA and bud pollination were ineffective. Numerous fruits with few embryos were obtained on some of theC. melolines after using the irradiated mentor pollen technique. Embryos, which were isolated at the age of 20–25 days and cultured on medium consisting of 1/3 Murashige and Skoog medium, were observed to provide normal development. All nine surviving plants were similar to the maternal parent and were not interspecific hybrids.

scholarly journals Foliar Application of Boron to Almond Trees Affects Pollen Quality

2000 ◽  
Vol 125 (2) ◽  
pp. 265-270 ◽  
Author(s):  
A.M.S. Nyomora ◽  
P.H. Brown ◽  
K. Pinney ◽  
V.S. Polito
Keyword(s):  
Pollen Germination ◽  
Foliar Application ◽  
Culture Media ◽  
Pollen Viability ◽  
Prunus Dulcis ◽  
Pollen Tubes ◽  
Tube Growth ◽  
Mature Trees

The effect of boron (B) on in vivo and in vitro development of almond [Prunus dulcis (Mill.) D.A. Webb (syn. P. amygdalus Batsch)] pollen and pollen tubes and the resultant effect on fruit set was studied in mature trees. The cultivars Mono (pistil donor) and Butte (pollinizer) in an orchard with low soil B in Fresno, California were sprayed with B at 0, 0.8, 1.7, or 2.5 kg·ha-1 during Fall 1993. Pollen viability as indicated by the fluorescein diacetate method (FDA) was >85% and was not affected by field-applied B, however, in vivo pollen germination and tube growth were enhanced by foliar-applied B. More effect of applied B on in vivo growth appeared as pollen tubes progressed toward the ovary. For in vitro germination, foliar-applied B reduced bursting of tubes, and addition of B to the culture media significantly increased pollen germination and pollen tube growth.

Differentiation of Human Embryonal Carcinomas In vitro and In vivo Reveals Expression Profiles Relevant to Normal Development

2005 ◽  
Vol 65 (13) ◽  
pp. 5588-5598 ◽  
Author(s):  
Rolf I. Skotheim ◽  
Guro E. Lind ◽  
Outi Monni ◽  
Jahn M. Nesland ◽  
Vera M. Abeler ◽  
...  
Keyword(s):  
Normal Development ◽  
Expression Profiles

scholarly journals Inhibition of β-Catenin Activity Abolishes LKB1 Loss-Driven Pancreatic Cystadenoma in Mice

2021 ◽  
Vol 22 (9) ◽  
pp. 4649
Author(s):  
Mei-Jen Hsieh ◽  
Ching-Chieh Weng ◽  
Yu-Chun Lin ◽  
Chia-Chen Wu ◽  
Li-Tzong Chen ◽  
...  
Keyword(s):  
Normal Development ◽  
Genetic Alterations ◽  
Epithelial Polarity ◽  
The Past ◽  
Upstream Kinase ◽  
Pancreatic Cystadenoma ◽  
Peutz Jeghers Syndrome ◽  
Functional Analyses

Pancreatic cancer (PC) is the seventh leading cause of cancer death worldwide, and remains one of our most recalcitrant and dismal diseases. In contrast to many other malignancies, there has not been a significant improvement in patient survival over the past decade. Despite advances in our understanding of the genetic alterations associated with this disease, an incomplete understanding of the underlying biology and lack of suitable animal models have hampered efforts to develop more effective therapies. LKB1 is a tumor suppressor that functions as a primary upstream kinase of adenine monophosphate-activated protein kinase (AMPK), which is an important mediator in the regulation of cell growth and epithelial polarity pathways. LKB1 is mutated in a significant number of Peutz–Jeghers syndrome (PJS) patients and in a small proportion of sporadic cancers, including PC; however, little is known about how LKB1 loss contributes to PC development. Here, we report that a reduction in Wnt/β-catenin activity is associated with LKB1 tumor-suppressive properties in PC. Remarkably, in vivo functional analyses of β-catenin in the Pdx-1-Cre LKB1L/L β-cateninL/L mouse model compared to LKB1 loss-driven cystadenoma demonstrate that the loss of β-catenin impairs cystadenoma development in the pancreas of Pdx-1Cre LKB1L/L mice and dramatically restores the normal development and functions of the pancreas. This study further determined the in vivo and in vitro therapeutic efficacy of the β-catenin inhibitor FH535 in suppressing LKB1 loss-driven cystadenoma and reducing PC progression that delineates the potential roles of Wnt/β-catenin signaling in PC harboring LKB1 deficiency.

scholarly journals Neurabin-I Is Phosphorylated by Cdk5: Implications for Neuronal Morphogenesis and Cortical Migration

2007 ◽  
Vol 18 (11) ◽  
pp. 4327-4342 ◽  
Author(s):  
Frédéric Causeret ◽  
Tom Jacobs ◽  
Mami Terao ◽  
Owen Heath ◽  
Mikio Hoshino ◽  
...  
Keyword(s):  
Hippocampal Neurons ◽  
Pyramidal Neurons ◽  
Normal Development ◽  
Phosphorylation Site ◽  
Neuronal Morphology ◽  
Actin Binding ◽  
Neuronal Morphogenesis ◽  
And Migration

The correct morphology and migration of neurons, which is essential for the normal development of the nervous system, is enabled by the regulation of their cytoskeletal elements. We reveal that Neurabin-I, a neuronal-specific F-actin–binding protein, has an essential function in the developing forebrain. We show that gain and loss of Neurabin-I expression affect neuronal morphology, neurite outgrowth, and radial migration of differentiating cortical and hippocampal neurons, suggesting that tight regulation of Neurabin-I function is required for normal forebrain development. Importantly, loss of Neurabin-I prevents pyramidal neurons from migrating into the cerebral cortex, indicating its essential role during early stages of corticogenesis. We demonstrate that in neurons Rac1 activation is affected by the expression levels of Neurabin-I. Furthermore, the Cdk5 kinase, a key regulator of neuronal migration and morphology, directly phosphorylates Neurabin-I and controls its association with F-actin. Mutation of the Cdk5 phosphorylation site reduces the phenotypic consequences of Neurabin-I overexpression both in vitro and in vivo, suggesting that Neurabin-I function depends, at least in part, on its phosphorylation status. Together our findings provide new insight into the signaling pathways responsible for controlled changes of the F-actin cytoskeleton that are required for normal development of the forebrain.

scholarly journals Ehretia pubescens Benth. with differential germinability patterns due to climate change

2017 ◽  
Vol 6 (06) ◽  
pp. 1630
Author(s):  
Amalaurpava Mary Michael* ◽  
Gopal G.V.
Keyword(s):  
Climate Change ◽  
Fruit Set ◽  
Pollen Viability ◽  
Natural Habitat ◽  
Flowering Phenology ◽  
Flowering Pattern ◽  
Floral Phenology ◽  
The Impact

Climate change may influence the composition of plant communities by affecting the reproduction, growth, establishment and local extinction of plant species. Predicting the effect of climate change may provide insight into the impact and relationship between weather pattern and flowering phenology in long term studies. Pollen viability is one important factor of reproduction. Pollen viability is essential for a good fruit set. The study is undertaken to evaluate the influence of temperature and rainfall fluctuation pattern on floral phenology and pollen viability in the restricted distribution of the plant Ehretia pubescens Benth. Field observation on floral phenology has revealed changes occurring in the pollen viability with the change of temperature and rainfall. The plants show drought resistant; however, it is observed that it blooms immediately after the rainfall. Change in the rainfall pattern results in change in flowering pattern. On the natural habitat fruit set is a good indicating of good germinability of pollen grain in vivo. In vitro pollen germinability is less efficient for this species as supported by the data.

scholarly journals Isolation of living sperm cells and in vitro fusion of Torenia fournieri gametes

2006 ◽  
Vol 12 (4) ◽  
Author(s):  
P. Vági ◽  
K. Imre ◽  
Z. Kristóf
Keyword(s):  
Male Gametophyte ◽  
Embryo Sac ◽  
Pollen Tubes ◽  
Sperm Cells ◽  
Torenia Fournieri ◽  
Isolation Medium ◽  
Vitro Fertilization ◽  
Crucial Part

In contrast to most angiosperms, Torenia contains a naked embryo sac and therefore has been considered since many years as an exciting model plant to study the double fertilization process of flowering seed plants. It is thus not surprising that the isolation of protoplasts from the female gametophyte has been reported already 20 years ago by Mol, the isolation of megaspores and megagametophytes has been published by the authors of this manuscript in 1996 and in 1999. The isolation of the male gametophyte and of sperm cells was published by the authors in 2004. The isolation of viable Torenia sperm cells is a crucial part of the elaboration of an in vitro fertilization system. Torenia sperm cells were isolated from in vivo — in vitro cultured pollen tubes. In this system pollen tubes first grow inside a cut style then follow their elongation in a solid isolation medium. The medium contained agarose in order to detain pollen tube contents. Released sperm cells and enzymatically isolated egg cells were collected and handled using glass micropipettes and transmitted to an electrofusion apparatus or polyethylene glycol containing media for fusion probes.

scholarly journals Pollen Tube Growth in Carya and Temporal Influence of Pollen Deposition on Fertilization Success in Pecan

1992 ◽  
Vol 117 (2) ◽  
pp. 328-331 ◽  
Author(s):  
Robert D. Marquard
Keyword(s):  
Pollen Tube ◽  
Pollen Tube Growth ◽  
Pollen Tubes ◽  
Fertilization Success ◽  
Tube Growth ◽  
In Vivo Studies ◽  
Pollen Deposition ◽  
Cape Fear

In vivo pollen tube growth of pecan [Carya illinoinensis (Wangenh.) K. Koch] was estimated to be ≈ 150 μm·hour-1 from 3 to 8 hours postpollination. Pollen tubes averaged 47, 194, 405, and 946 μm after 2, 3, 4, and 8 hours postpollination, respectively. Pollen tube growth was strongly influenced by temperature, and in vitro studies demonstrated pollen germination and tube growth were optimal at 27C for `Cape Fear' pecan. In in vivo studies, tubes of cross-pollen did not grow significantly faster than tubes of self-pollen. Pollen tubes of water hickory [C. aquatica (Michx. f.) Nutt.] grew significantly faster than those of C. illinoinensis. Bitternut [C. cordiformis (Wangenh.) K. Koch] and mockernut hickory (C. tomentosa Nutt.) pollen tubes grew significantly slower on pecan stigmas than did pecan pollen. Pollen arriving first on the stigma has a decided advantage for fertilization success of pecan. The fertilization success rate of pecan pollen arriving 24 hours after first pollen arrival was <3%.

scholarly journals Investigations of suitable pollinator for 0900 Ziraat sweet cherry cv.: pollen performance tests, germination tests, germination procedures, in vitro and in vivo pollinations

2008 ◽  
Vol 34 (No. 2) ◽  
pp. 47-53 ◽  
Author(s):  
F. Tosun ◽  
F. Koyuncu
Keyword(s):  
Pollen Tube ◽  
Pollen Germination ◽  
Sweet Cherry ◽  
Fruit Set ◽  
Pollen Viability ◽  
Performance Tests ◽  
Pollen Performance ◽  
Growth Experiments

The objective of this study was to determine suitable cultivars to be used as pollinators for 0900 Ziraat. 0900 Ziraat was used as a female cultivar; Bigarreu Gaucher, Bing, Noble, Starks Gold, Stella, Van, and Vista were used for pollination in the experiments. Starks Gold had the highest values in terms of anther number, average number of pollens per anther, number of pollen per flower and the morphological homogeneity. The pollen viability rates showed significant differences according to stain tests. <i>In vitro</i> pollen germination in 0.5% agar + 15% sucrose + 5 ppm boric acid medium increased with increasing incubation period, and the highest germination was obtained after 48 hours for all cultivars. In orchard trials parallel to pollen tube growth experiments in the laboratory, 0900 Ziraat &times; Starks Gold combination gave the best fruit set results.

Boosting the Food Functionality (In Vivo and In Vitro) of Spirulina by Gamma Radiation: An Inspiring Approach

2015 ◽  
Vol 11 (4) ◽  
pp. 579-585 ◽  
Author(s):  
Jahid M. M. Islam ◽  
Md. Ismail ◽  
Md. Rakibul Islam ◽  
Md. Faruk Hossain ◽  
Hossain Uddin Shekhar
Keyword(s):  
Radiation Dose ◽  
Gamma Radiation ◽  
Binding Capacity ◽  
Chemical Properties ◽  
Maximum Level ◽  
Biologically Active ◽  
Optimum Dose ◽  
Radiation Doses

Abstract Foods (natural or processed) containing known biologically active compounds, which supplies clinically established and well-documented health benefits, are termed as functional food. Study objectives were to boost food functionality of spirulina, to optimize the required radiation dose, and to test functionality of spirulina both in vitro and in vivo. For this purpose fat binding capacity, sugar binding capacity, hydration property, antioxidative property, total polyphenol content were assessed at different radiation doses. A total of 30 rats were divided into three groups to carry out in vivo experiments to validate the outcomes of in vitro experiments. Targeted physico-chemical properties of spirulina were increased at their maximum level at 15 kGy radiation dose. In vivo experiments validated the outcomes of in vitro experiments. Though gamma radiation improves food functionality of spirulina at various radiation doses, but the optimum dose is recommended as 15 kGy.

polyhomeotic appears to be a target of engrailed regulation in Drosophila

Development ◽  
1995 ◽  
Vol 121 (6) ◽  
pp. 1691-1703 ◽  
Author(s):  
N. Serrano ◽  
H.W. Brock ◽  
C. Demeret ◽  
J.M. Dura ◽  
N.B. Randsholt ◽  
...  
Keyword(s):  
Binding Sites ◽  
Normal Development ◽  
Regulatory Protein ◽  
Polytene Chromosomes ◽  
Polycomb Group ◽  
Germ Band ◽  
High Affinity ◽  
Embryonic Segmentation

In Drosophila, Engrailed is a nuclear regulatory protein with essential roles in embryonic segmentation and in normal development of posterior compartments. One of its regulatory targets appears to be polyhomeotic (ph), a Polycomb group gene. We observed, by immunostaining, that Engrailed protein binds to the site of the polyhomeotic locus in region 2D of polytene chromosomes. The same analysis carried out on a transgenic line containing one copy of a P(ph-lacZ) construct shows an additional Engrailed-binding site at the location of the insert. In vivo, polyhomeotic depends on engrailed function in germ-band-elongated embryos, when engrailed and polyhomeotic genes are expressed in similar patterns. By in vitro immunoprecipitations and gel shift assays, we identified two classes of high affinity Engrailed-binding sites upstream of each of the two polyhomeotic transcription units. DNA fragments containing these sites were also immunoprecipitated from embryonic UV crosslinked chromatin in presence of anti-Engrailed antibody. These results suggest that polyhomeotic activation in germ-band-elongated embryos could be mediated by Engrailed-binding to these sites.

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