Search results for "Organogenesis"
showing 10 items of 48 documents
Micropropagation of Citrus spp. by Organogenesis and Somatic Embryogenesis.
2013
Citrus spp., the largest fruit crops produced worldwide, are usually asexually propagated by cuttings or grafting onto seedling rootstocks. Most of Citrus genotypes are characterized by polyembryony due to the occurrence of adventive nucellar embryos, which lead to the production of true-to-type plants by seed germination. Tissue culture and micropropagation, in particular, are valuable alternatives to traditional propagation to obtain a high number of uniform and healthy plants in a short time and in a small space. Moreover, in vitro propagation provides a rapid system to multiply the progeny obtained by breeding programs, allows the use of monoembryonic and seedless genotypes as rootstock…
Flowers and inflorescences of the seagrassPosidonia(Posidoniaceae, Alismatales)
2012
Premise of the study: The predominantly aquatic order Alismatales displays a highly variable fl ower groundplan associated with a diverse range of developmental patterns. We present the fi rst detailed description of fl ower anatomy and development in Posidonia , the sole genus of the seagrass family Posidoniaceae. Existing accounts provide confl icting interpretations of fl oral and infl orescence structure, so this investigation is important in clarifying morphological evolution within this early-divergent monocot order. • Methods: We investigated two species of Posidonia using light microscopy and scanning electron microscopy. Our observations are interpreted in the framework of a recent…
Evidence for pleural epithelial-mesenchymal transition in murine compensatory lung growth
2017
In many mammals, including rodents and humans, removal of one lung results in the compensatory growth of the remaining lung; however, the mechanism of compensatory lung growth is unknown. Here, we investigated the changes in morphology and phenotype of pleural cells after pneumonectomy. Between days 1 and 3 after pneumonectomy, cells expressing α-smooth muscle actin (SMA), a cytoplasmic marker of myofibroblasts, were significantly increased in the pleura compared to surgical controls (p < .01). Scanning electron microscopy of the pleural surface 3 days post-pneumonectomy demonstrated regions of the pleura with morphologic features consistent with epithelial-mesenchymal transition (EMT); nam…
Perlecan controls neurogenesis in the developing telencephalon.
2006
This article is available from: http://www.biomedcentral.com/1471-213X/7/29
UNC-52/perlecan affects gonadal leader cell migrations in C. elegans hermaphrodites through alterations in growth factor signaling.
2003
0012-1606 doi: DOI: 10.1016/S0012-1606(03)00014-9; The unc-52 gene of Claenorhabditis elegans encodes a homologue of the basement membrane heparan sulfate proteoglycan perlecan. Viable alleles reduce the abundance of UNC-52 in late larval stages and increase the frequency of distal tip cell (DTC) migration defects caused by mutations disrupting the UNC-6/netrin guidance system. These unc-52 alleles do not cause circumferential DTC migration defects in an otherwise wild-type genetic background. The effects of unc-52 mutations on DTC migrations are distinct from effects on myofilament organization and can be partially suppressed by mutations in several genes encoding growth factor-like molecu…
Serpent and a hibris reporter are co-expressed in migrating cells during Drosophila hematopoiesis and Malpighian tubule formation
2006
Motile mesodermal cells contribute several cell types to developing embryos. In Drosophila, blood cell precursors or prohemocytes, are first detected in the procephalic mesoderm by the expression of the GATA transcription factor Serpent. Once specified, a subset of prohemocytes migrate posteriorly to populate most of the embryo and further differentiate as plasmatocytes. Similarly, Drosophila nephrogenesis involves integration of posterior mesodermal cells into the Malpighian tubule primordia where these cells differentiate as stellate cells. Here we investigated the possibility that the immunoglobulin-domain protein Hibris and the GATA factor Serpent were co-expressed in motile mesodermal …
Intraflagellar transport proteins in ciliogenesis of photoreceptor cells
2011
Background information. The assembly and maintenance of cilia depend on IFT (intraflagellar transport) mediated by molecular motors and their interplay with IFT proteins. Here, we have analysed the involvement of IFT proteins in the ciliogenesis of mammalian photoreceptor cilia. Results. Electron microscopy revealed that ciliogenesis in mouse photoreceptor cells follows an intracellular ciliogenesis pathway, divided into six distinct stages. The first stages are characterized by electron-dense centriolar satellites and a ciliary vesicle, whereas the formations of the ciliary shaft and the light-sensitive outer segment discs are features of the later stages. IFT proteins were associated with…
Human brain organoids assemble functionally integrated bilateral optic vesicles
2021
During embryogenesis, optic vesicles develop from the diencephalon via a multistep process of organogenesis. Using induced pluripotent stem cell (iPSC)-derived human brain organoids, we attempted to simplify the complexities and demonstrate formation of forebrain-associated bilateral optic vesicles, cellular diversity, and functionality. Around day 30, brain organoids attempt to assemble optic vesicles, which develop progressively as visible structures within 60 days. These optic vesicle-containing brain organoids (OVB-organoids) constitute a developing optic vesicle's cellular components, including primitive corneal epithelial and lens-like cells, retinal pigment epithelia, retinal progeni…
Morpholino knockdown of the ubiquitously expressed transmembrane serine protease TMPRSS4a in zebrafish embryos exhibits severe defects in organogenes…
2011
AbstractOver the past years the members of the type II transmembrane serine protease (TTSP) family have emerged as new players in mammalian biology. TMPRSS4 (transmembraneprotease/serine) is overexpressed in several human cancer tissues, promoting invasion, migration, and metastasis. However, the physiological function has not yet been elucidated. Here, we present morpholino knockdown studies targeting TMPRSS4a, a homolog of human TMPRSS4 in zebrafish embryos. By RT-PCR, we could demonstrate an expression of this protease already 5 h post-fertilization, suggesting important functions in the early stages of embryonic development. Indeed,in vivogene silencing caused severe defects in tissue d…
Citrus biotechnology
2020
Agricultural crops that can better withstand the changing climatic and pathogen landscape have been produced through natural selection throughout the millennia and, in recent years, through the process of human-assisted plant breeding and selection. However, a lack of genetic diversity in many commercially cultivated crops (due to monoculture) has made them more vulnerable to biotic and abiotic stresses (Esquinas-Alcazar, 2005; Keneni et al., 2012). Citrus, belonging to the Rutaceae family, is one of the most important commercial woody fruit crops in the tropical and subtropical areas of the world. The origin of citrus is traced back to parts of tropical and subtropical Southeast Asia (Wu e…