Search results for "haploid"
showing 10 items of 51 documents
STUDY ON ISOLATED MICROSPORE CULTURE IN CITRUS SINENSIS L. OSBECK CV. MORO, A BLOOD ORANGE CULTIVAR
2014
In vitro tissue culture represents a useful support for the advancement of Citrus breeding and propagation. Haploidy technology, that is the single-step development of complete homozygous genotypes from heterozygous parents through gametic embryogenesis, has already a huge impact on many relevant crops, representing an integral part in their breeding programmes (Germanà 2011a; 2011b). In order to increase the number of genotypes responding to gametic embryogenesis, in vitro isolated microspore culture of Citrus sinensis L. Osbeck cv. Moro, has been carried out, investigating the influence of the culture medium composition, and, particularly, of the plant growth regulator types and concentra…
A singular case of near-haploid stemline karyotype in a renal oncocytoma.
1996
Cytogenetic analysis of a human renal oncocytoma revealed a near-haploid chromosome number of 36 with the loss of chromosomes 1, 2, 3, 6, 8, 9, 15, 17, 21, and 22. Review of the literature disclosed that this cytogenetic configuration is extremely rare in solid human tumors and that no renal oncocytomas with near-haploid stemline karyotype have been described. These results are compared with the other published cases of oncocytoma.
DNA content in nine species of Nematocera with special reference to the sibling species of the Anopheles maculipennis group and the Culex pipiens gro…
1972
DNA values were determined for the nine species: Telmatoscopus meridionalis (family Psychodidae), Dixa obscura (family Dixidae), and Culiseta litorea, Culex pipiens, Aedes caspius, Anopheles labranchiae, Anopheles atroparvus, Anopheles stephensi, and Anopheles freeborni (family Culicidae). The DNA content indicated that the species could be divided into three categories: The Culex group with Culex pipiens, Culiseta litorea and Aedes caspius containing 1.02, 0.92 and 0.99 pg DNA in the haploid set, the Anopheles group including the four Anopheles species A. labranchiae, A. atroparvus, A. stephensi, A. freeborni and Telmatoscopus meridionalis with 0.23, 0.24, 0.24, 0.29 and 0.24 pg DNA and th…
PSCDGs of mouse multipotent adult germline stem cells can enter and progress through meiosis to form haploid male germ cells in vitro
2010
Spermatogonial stem cells (SSCs) provide the basis for spermatogenesis throughout adult life by undergoing self-renewal and differentiation into sperm. SSC-derived cell lines called multipotent adult germline stem cells (maGSCs) were recently shown to be pluripotent and to have the same potential as embryonic stem cells (ESCs). In a differentiation protocol using retinoic acid (RA) and based on a double selection strategy, we have shown that ESCs are able to undergo meiosis and produce haploid male germ cells in vitro. Using this differentiation protocol we have now succeeded to generate haploid male germ cells from maGSCs in vitro. maGSCs derived from a Stra8-EGFP transgenic mouse line wer…
Does haplodiploidy purge inbreeding depression in rotifer populations?
2009
Background Inbreeding depression is an important evolutionary factor, particularly when new habitats are colonized by few individuals. Then, inbreeding depression by drift could favour the establishment of later immigrants because their hybrid offspring would enjoy higher fitness. Rotifers are the only major zooplanktonic group where information on inbreeding depression is still critically scarce, despite the fact that in cyclical parthenogenetic rotifers males are haploid and could purge deleterious recessive alleles, thereby decreasing inbreeding depression. Methodology/Principal Findings We studied the effects of inbreeding in two populations of the cyclical parthenogenetic rotifer Brach…
Unmatedness promotes the evolution of helping more in diplodiploids than in haplodiploids
2014
The predominance of haplodiploidy (where males develop from unfertilized haploid eggs and females from fertilized diploid eggs) among eusocial species has inspired a body of research that focuses on the possible role of relatedness asymmetries in the evolution of helping and eusociality. Previous theory has shown that in order for relatedness asymmetries to favor the evolution of helping, there needs to be variation in sex ratios among nests in the population (i.e., split sex ratios). In haplodiploid species, unmated females can produce a brood of all males, and this is considered the most likely mechanism for split sex ratios at the origin of helping. In contrast, in diploidiploids unmated…
Human somatic cells subjected to genetic induction with six germ line-related factors display meiotic germ cell-like features
2016
AbstractThe in vitro derivation of human germ cells has attracted interest in the last years, but their direct conversion from human somatic cells has not yet been reported. Here we tested the ability of human male somatic cells to directly convert into a meiotic germ cell-like phenotype by inducing them with a combination of selected key germ cell developmental factors. We started with a pool of 12 candidates that were reduced to 6, demonstrating that ectopic expression of the germ line-related genes PRDM1, PRDM14, LIN28A, DAZL, VASA and SYCP3 induced direct conversion of somatic cells (hFSK (46, XY) and hMSC (46, XY)) into a germ cell-like phenotype in vitro. Induced germ cell-like cells …
Tracking paternal genes with DALP markers in a pseudoarrhenotokous reproductive system: biparental transmission but haplodiploid-like inheritance in …
2000
International audience; The complexity of some sexual reproductive systems in arthropods still leaves both their genetic and epigenetic determinism and their evolutionary significance poorly understood. Pseudoarrhenotoky is characterized by obligate fertilization and differential inactivation and/or elimination of paternal chromosomes in embryos that develop into males. Here, we investigate how the paternal genome is transmitted in a pseudoarrhenotokous mite, Neoseiulus californicus, using codominant genetic markers detected by DALP (direct amplification of length polymorphism). Transmission patterns of parental alleles through one and two generations are reported at four or five loci corre…
Haploinsufficiency of ATP1A2 encoding the Na+/K+ pump alpha2 subunit associated with familial hemiplegic migraine type 2.
2003
Headache attacks and autonomic dysfunctions characterize migraine, a very common, disabling disorder with a prevalence of 12% in the general population of Western countries(1,2). About 20% of individuals affected with migraine experience aura, a visual or sensory-motor neurological dysfunction that usually precedes or accompanies the headache(3). Although the mode of transmission is controversial(4), population-based and twin studies have implicated genetic factors, especially in migraine with aura(5,6). Familial hemiplegic migraine is a hereditary form of migraine characterized by aura and some hemiparesis. Here we show that mutations in the gene ATP1A2 that encodes the alpha2 subunit of t…
FIRST STAGES OF MICROSPORE REPROGRAMMING TO EMBRYOGENESIS THROUGH ISOLATED MICROSPORE CULTURE IN LOQUAT
2011
The current experiments were undertaken to develop a method for regenerating doubled haploid (DH) plants of Eriobotrya japonica (Thunb.), Rosaceae, subfamily Maloideae through isolated microspore culture of nine loquat cultivars. Protocols were developed for isolation and culture of loquat microspores. Isolated microspores in vitro cultured started dividing and developing multicellular, globular and irregular structures. After 4 weeks of culture, the responding microspores produced yellowish/white callus. The embryogenic response of microspores was highly dependent on the cultivar and on the medium composition.