Search results for "ploidy"

Microspore Embryogenesis in Citrus

2021

This chapter deals with microspore embryogenesis in Citrus. Microspore embryogenesis allows to induce immature gametes (microspores) and to deviate them, in this case, the male one, from the normal gametophytic developmental route in the direction of the sporophytic one, yielding homozygous organisms (embryos and plants).

First stages of microsporere programming to embryogenesis through anther culture in Prunus armeniaca L.

2011

6 páginas, 3 figuras, 2 tablas -- PAGS nros. 152-157

Early induction of genetic instability and apoptosis by arsenic in cultured Chinese hamster cells

2002

In order to assess at what time from the beginning of exposure inorganic arsenic can give rise to genetic instability and trigger apoptosis, V79-C13 Chinese hamster cells were treated with 10 microM sodium arsenite for 24 h. Under these conditions, cell survival was >70% and cells showed neither an increase in chromosome aberration frequency nor a delay in cell cycle progression. Investigations, which were carried out every 6 h during the treatment, revealed an early appearance of genetically unstable cells, namely micronucleated, multinucleated and mononucleated 'giant' cells, as well as apoptotic cells. Indirect immunostaining using anti-beta-tubulin antibody showed severe alterations in …

Reciprocal hybridization at different times between Senecio flavus and Senecio glaucus gave rise to two polyploid species in north Africa and south‐w…

2006

Summary • The analysis of hybrid plant taxa using molecular methods has considerably extended understanding of possible pathways of hybrid evolution. • Here, we investigated the origin of the tetraploid Senecio mohavensis ssp. breviflorus and the hexaploid Senecio hoggariensis by sequencing of nuclear and chloroplast DNA, and by analysis of the distribution of taxon-specific amplified fragment length polymorphism (AFLP) fragments. • Both taxa originated from hybridization between the diploid Senecio flavus and Senecio glaucus. Whereas S. glaucus was the female parent in the origin of S. mohavensis ssp. breviflorus, S. flavus was the female parent in the origin of S. hoggariensis. • The dist…

The marbled crayfish as a paradigm for saltational speciation by autopolyploidy and parthenogenesis in animals

2015

ABSTRACT The parthenogenetic all-female marbled crayfish is a novel research model and potent invader of freshwater ecosystems. It is a triploid descendant of the sexually reproducing slough crayfish, Procambarus fallax, but its taxonomic status has remained unsettled. By cross-breeding experiments and parentage analysis we show here that marbled crayfish and P. fallax are reproductively separated. Both crayfish copulate readily, suggesting that the reproductive barrier is set at the cytogenetic rather than the behavioural level. Analysis of complete mitochondrial genomes of marbled crayfish from laboratory lineages and wild populations demonstrates genetic identity and indicates a single o…

Chromosome numbers in plant taxa endemic to the Balearic Islands

2005

Mitotic chromosome numbers are reported from 20 vascular plant taxa that are endemic to the Balearic Islands and poorly known cytogenetically. The chromosome numbers of Arenaria grandiflora L. ssp. glabrescens (Willk.) G. Lopez & Nieto Feliner (2n = 44), Dianthus rupicola Viv. ssp. bocchoriana L. Llorens & Gradaille (2n = 30), Solenopsis minuta (L.) C. Presl. ssp. balearica (E. Wimm.) Meikle (2n = 28), Romulea asumptionis Font Quer & Garcias Font (2n = 56), Scutellaria balearica Barcelo (2n = 22) and Galium balearicum Briq. (2n = 22) have been determined for the first time. A new chromosome number was found in two populations of Helictotrichon crassifolium (Font Quer) Holub (2n = c. 98) sug…

Pathogenic correlation between mosaic variegated aneuploidy 1 (MVA1) and a novel BUB1B variant: a reappraisal of a severe syndrome.

2022

Funder: Università degli Studi di Catania

Typification of Dactylis ibizensis (Poaceae) and inference of the ploidy level of the type specimen

2021

Transcriptomic Changes Following Partial Depletion of CENP-E in Normal Human Fibroblasts

2021

The centromere is a fundamental chromosome structure in which the macro-molecular kinetochore assembles and is bound by spindle microtubules, allowing the segregation of sister chromatids during mitosis. Any alterations in kinetochore assembly or functioning or kinetochore–microtubule attachments jeopardize chromosome stability, leading to aneuploidy, a common feature of cancer cells. The spindle assembly checkpoint (SAC) supervises this process, ensuring a faithful segregation of chromosomes. CENP-E is both a protein of the kinetochore and a crucial component of the SAC required for kinetochore–microtubule capture and stable attachment, as well as congression of chromosomes to the metaphas…

MYCN gain and MYCN amplification in a stage 4S neuroblastoma.

2003

Abstract Stage 4S neuroblastoma is a disease associated with spontaneous regression and good survival. We present a patient whose evolution has shown the variety and complexity of this disease in infants. Biologic factors, such as ploidy, MYCN copy number, loss of 1p36, and other chromosomal gains and losses were determined. A complex pattern of genetic abnormalities, such as near-diploidy, MYCN gain (2–4 copies per haploid genome) and imbalance/deletion of 1p36 was seen in the diagnostic sample. An extensive disseminated disease after a latent period of 26 months was associated with a special genetic evolution, such as tetraploidy, MYCN amplification (2:100–500 copies), 1p36 deletion, and …