Mangrove Genetics. IV. Postzygotic Mutations Fixed as Periclinal Chimeras

1996 ◽  
Vol 157 (4) ◽  
pp. 398-405 ◽  
Author(s):  
Edward J. Klekowski, ◽  
Robin Lowenfeld ◽  
Elizabeth H. Klekowski
Keyword(s):  
Periclinal Chimeras ◽  
Postzygotic Mutations

Non-cell-autonomous function of the Antirrhinum floral homeotic proteins DEFICIENS and GLOBOSA is exerted by their polar cell-to-cell trafficking

Development ◽  
1996 ◽  
Vol 122 (11) ◽  
pp. 3433-3441 ◽  
Author(s):  
M.C. Perbal ◽  
G. Haughn ◽  
H. Saedler ◽  
Z. Schwarz-Sommer
Keyword(s):  
Cell Layer ◽  
Epidermal Cells ◽  
Molecular Techniques ◽  
Cell Trafficking ◽  
Mads Box ◽  
Organ Identity ◽  
Cell Layers ◽  
Periclinal Chimeras ◽  
The Difference ◽  
Cell Autonomy

In Antirrhinum majus, petal and stamen organ identity is controlled by two MADS-box transcription factors, DEFICIENS and GLOBOSA. Mutations in either of these genes result in the replacement of petals by sepaloid organs and stamens by carpelloid organs. Somatically stable def and glo periclinal chimeras, generated by transposon excision events, were used to study the non-cell-autonomous functions of these two MADS-box proteins. Two morphologically distinct types of chimeras were analysed using genetic, morphological and molecular techniques. Restoration of DEF expression in the L1 cell layer results in the reestablishment of DEF and GLO functions in L1-derived cells only; inner layer cells retain their mutant sepaloid features. Nevertheless, this activity is sufficient to allow the expansion of petal lobes, highlighting the role of DEF in the stimulation of cell proliferation and/or cell shape and elongation when expressed in the L1 layer. Establishment of DEF or GLO expression in L2 and L3 cell layers is accompanied by the recovery of petaloid identity of the epidermal cells but it is insufficient to allow petal lobe expansion. We show by in situ immunolocalisation that the non-cell-autonomy is due to direct trafficking of DEF and GLO proteins from the inner layer to the epidermal cells. At least for DEF, this movement appears to be polar since DEF acts cell-autonomously when expressed in the L1 cell layer. Furthermore, the petaloid revertant sectors observed on second whorl mutant organs and the mutant margins of petals of L2L3 chimeras suggest that DEF and GLO intradermal movement is limited. This restriction may reflect the difference in the regulation of primary plasmodesmata connecting cells from the same layer and secondary plasmodesmata connecting cells from different layers. We propose that control of intradermal trafficking of DEF and GLO could play a role in maintaining of the boundaries of their expression domains.

Becker's Nevus Syndrome

2018 ◽  
Vol 16 (05) ◽  
pp. 352-361 ◽  
Author(s):  
Maria Cucuzza ◽  
Sara Paternò ◽  
Stefano Catanzaro ◽  
Agata Polizzi ◽  
Carmelo Schepis ◽  
...  
Keyword(s):  
Natural History ◽  
Soft Tissues ◽  
Cutaneous Lesion ◽  
Simultaneous Occurrence ◽  
Pectus Carinatum ◽  
Epidermal Nevus ◽  
Becker’S Nevus ◽  
History Of ◽  
Prepubertal Boys ◽  
Postzygotic Mutations

The simultaneous occurrence of a patch of light or dark brown hyperpigmentation with hypertrichosis (Becker's nevus) together with (usually ipsilateral) soft tissues hypoplasia (especially breast, in women) and underlying skeletal anomalies (i.e., vertebral hypoplasia, scoliosis, pectus carinatum or excavatum) represents the Becker's nevus syndrome (BNS) phenotype. It was first described (as a single cutaneous lesion) by Becker in 1949 and then associated with the surrounding musculoskeletal disorders. The syndrome has also been reported as pigmentary hairy epidermal nevus syndrome. Less than 100 cases have been reported in the literature, with a slightly higher incidence in females and only few familiar cases: paradominant postzygotic mutations and/or an androgen-dependent hyperactivation have been reported as the causes of the diseases.The extracutaneous lesions are congenital and nonprogressive, and the natural history of the Becker's nevus is the same as that of isolated nevi: in prepubertal boys, the pigmentation may be less intense and the hairiness may be absent or mild, as occurs in women, whereas in men, there is an increase of hairiness after puberty. The treatment is essentially cosmetic, and potential therapeutic options include electrolysis, waxing, makeup, or laser.

Cutis Tricolor

2018 ◽  
Vol 16 (05) ◽  
pp. 276-281
Author(s):  
Martino Ruggieri ◽  
Agata Polizzi ◽  
Selene Mantegna ◽  
Chiara Battaglini ◽  
Concetta Pirrone ◽  
...  
Keyword(s):  
Normal Skin ◽  
Distinct Type ◽  
Skin Lesions ◽  
Nasal Bridge ◽  
Phacomatosis Pigmentovascularis ◽  
Skeletal Defects ◽  
Skin Abnormalities ◽  
Vertebral Defects ◽  
Postzygotic Mutations ◽  
Over Time

AbstractCutis tricolor is a skin abnormality consisting in a combination of congenital hyper- and hypopigmented skin lesions (in the form of paired macules, patches, or streaks) in close proximity to each other in a background of normal skin. It is currently regarded as a twin-spotting (mosaic) phenomenon. This phenomenon has been reported so far as a purely cutaneous trait, as a part of a complex malformation phenotype (Ruggieri–Happle syndrome), which includes distinct facial features, cataract, skull and vertebral defects, long bones dysplasia, corpus callosum, cerebellar and white matter anomalies, cavum vergae and holoprosencephaly, and other systemic abnormalities. Cutis tricolor has been also reported as a distinct type with multiple, disseminated smaller skin macules (cutis tricolor parvimaculata) or in association with other skin disturbances (e.g., phacomatosis achromico-melano-marmorata) or in the context of other neurocutaneous phenotypes (e.g., ataxia-telangiectasia and phacomatosis pigmentovascularis) or as a sign of complex malformation phenotypes (e.g., microcephaly and dwarfism). More than 20 studies reporting 40 cases are present in the literature with pure cutaneous or syndromic cutis tricolor phenomena and are analyzed in the present study, confirming and expanding the overall phenotype of cutis tricolor. In particular, (1) the skin abnormalities of the cutis tricolor do not evolve over time; (2) there is a typical facial phenotype with long, elongated face, thick and brushy eyebrows, hypertelorism, deep nasal bridge with large bulbous nose, and anteverted nostrils; (3) the skeletal defects are mild-to-moderate and do not progress or cause relevant orthopedic complications; (4) the neurological/behavioral phenotype does not progress and the paroxysmal events (if present) tend to decrease over time; (5) only three patients developed early onset (treatable) cataracts. Different pathologic hypotheses have been postulated, including, early or late postzygotic mutations involving the same gene loci (in the context of the so-called dydymotic theory): such mechanisms can explain the overall skin, bone, lens, and nervous system phenomena of migration of different streaks of clones in the different tissues.

Stereological Analysis of the Dermal System of Fruit of the Grape Vitis vinifera L.

1981 ◽  
Vol 29 (4) ◽  
pp. 463 ◽  
Author(s):  
JA Considine
Keyword(s):  
Vitis Vinifera ◽  
Cellular Structure ◽  
Fruit Size ◽  
Cell Number ◽  
Fruit Shape ◽  
Vitis Vinifera L ◽  
Single Function ◽  
Periclinal Chimeras ◽  
Fruit Size And Shape ◽  
Fruit Surface

Changes in cell vdume and shape in different layers of the dermal system of the grape Vitis vinifera have been analysed in relation to position along the radius of the fruit and fruit shape. Fruit surface area was found to be a function of changes in both cell area and cell number, though cell number effects were predominant. Cell volume generally increased exponentially from the epidermis inwards, though no single function adequately described the pattern for all cultivars. Deviations from a continuous pattern of change of volume were compatible with the possible occurrence of polyploid periclinal chimeras or endoploids. These results suggest that differences in cellular structure were determined by mechanisms that were independent of potential stresses associated with differences in fruit size and shape.

Mosaicism due to postzygotic mutations in women with focal dermal hypoplasia

2018 ◽  
Vol 180 (3) ◽  
pp. 657-661 ◽  
Author(s):  
L. Heinz ◽  
E. Bourrat ◽  
P. Vabres ◽  
J. Thevenon ◽  
A. Hotz ◽  
...  
Keyword(s):  
Focal Dermal Hypoplasia ◽  
Postzygotic Mutations

PIK3CA-Related Overgrowth Spectrum

2019 ◽  
pp. 217-240
Author(s):  
Kim M. Keppler-Noreuil
Keyword(s):  
Cell Growth ◽  
Clinical Features ◽  
Tissue Specificity ◽  
Phenotypic Variability ◽  
Akt Pathway ◽  
Gain Of Function ◽  
Clinical Phenotypes ◽  
Segmental Overgrowth ◽  
Postzygotic Mutations ◽  
Cell Growth And Proliferation

Postzygotic mutations of the PIK3CA gene are associated with a series of clinical phenotypes characterized by segmental overgrowth and recently grouped under the term PIK3CA-related overgrowth spectrum (PROS). This chapter provides an overview of the clinical features shared by the phenotypes in PROS, including both the conditions with isolated features and the ones with syndromal presentation. The somatic overgrowth in cases with PROS is asymmetric, progressive, and “ballooning” in appearance and tends to involve predominantly the limbs, including fingers and toes, although the trunk and face are often affected as well. The tissues affected in the overgrowth can include all or some of these types: fibrous, adipose, vascular, nervous, and skeletal. Somatic gain-of-function mutations of PIK3CA cause activation of the PI3K-AKT pathway, leading to excessive cell growth and proliferation. Timing of PIK3CA mutations, tissue specificity, and type of mutation may play a role in the phenotypic variability of PROS.

FLOWER STRUCTURE IN PERICLINAL CHIMERAS OF APPLE

1950 ◽  
Vol 37 (4) ◽  
pp. 297-304 ◽  
Author(s):  
H. Weston Blaser ◽  
John Einset
Keyword(s):  
Flower Structure ◽  
Periclinal Chimeras

scholarly journals Color Intensity of the Red-Fleshed Berry Phenotype of Vitis vinifera Teinturier Grapes Varies Due to a 408 bp Duplication in the Promoter of VvmybA1

Genes ◽  
2020 ◽  
Vol 11 (8) ◽  
pp. 891
Author(s):  
Franco Röckel ◽  
Carina Moock ◽  
Ulrike Braun ◽  
Florian Schwander ◽  
Peter Cousins ◽  
...  
Keyword(s):  
Vitis Vinifera ◽  
Hplc Analysis ◽  
Economic Importance ◽  
Anthocyanin Content ◽  
Red Wines ◽  
Quantitative Real Time Pcr ◽  
Color Intensity ◽  
Repeat Number ◽  
Long Time ◽  
Periclinal Chimeras

Grapevine (Vitis vinifera) teinturier cultivars are characterized by their typical reddish leaves and red-fleshed berries due to ectopic anthocyanin formation. Wines of these varieties have economic importance as they can be used for blending to enhance the color of red wines. The unique and heritable mutation has been known for a long time but the underlying genetic mechanism still is not yet understood. Here we describe the association of the red-fleshed berry phenotype with a 408 bp repetitive DNA element in the promoter of the VvmybA1 gene (grapevine color enhancer, GCE). Three different clones of ‘Teinturier’ were discovered with two, three and five allelic GCE repeats (MybA1t2, MybA1t3 and MybA1t5). All three clones are periclinal chimeras; these clones share the same L1 layer, but have distinct L2 layers with different quantities of GCE repeats. Quantitative real time PCR and HPLC analysis of leaf and berry samples showed that the GCE repeat number strongly correlates with an increase of the expression of VvmybA1 itself and the VvUFGT gene regulated by it and the anthocyanin content. A model is proposed based on autoregulation of VvmybA1t to explain the red phenotype which is similar to that of red-fleshed apples. This study presents results about the generation and modes of action of three MybA1t alleles responsible for the red-fleshed berry phenotype of teinturier grapevines.

Genetic interaction between the tissues of carnation petals as periclinal chimeras

1974 ◽  
Vol 14 (2) ◽  
pp. 109-116 ◽  
Author(s):  
Pierre Pereau-Leroy
Keyword(s):  
Genetic Interaction ◽  
Periclinal Chimeras ◽  
Carnation Petals
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