Blackberry

Apomixis

Coprosma robusta

Asteraceae

Flowering plant

Botany

Blackberry

Apomixis9

• In sporophytic apomixis, the embryo forms directly from the somatic diploid ovule tissue (nucellus or integument). (frontiersin.org)
• Many higher plants of economic and biological importance undergo apomixis in which the maternal tissue of the ovule forms a seed, without experiencing meiosis and fertilization. (eurekamag.com)
• Observed changes in small RNA targets and biogenesis pathways within sexual and apomictic ovaries will underlie future functional research into apomixis initiation in Hieracium . (biomedcentral.com)
• As apomixis is not evident in major seed crops, isolation of genes from apomictic model species with the intention to transfer them to crops has been a major focus of research. (biomedcentral.com)
• Apomictic loci are often found to be associated with highly repetitive chromosomal regions where recombination is suppressed, and additional loci also appear to influence the penetrance of the apomixis phenotype [ 1 , 3 , 4 ]. (biomedcentral.com)
• To date, genes within apomictic loci which are capable of conferring apomixis phenotypes are largely unknown, with the exception of a recently identified gene from apomictic Pennisetum that stimulates fertilization-independent embryogenesis [ 5 ]. (biomedcentral.com)
• Apomixis genes have been transferred to the crop successfully through interspeci﫿c hybridization, and apomictic clones arising from these hybrids are now being grown at the Universidade de Brasília. (bvsalud.org)
• The living of apomixis in order Vistide an normally diploid sexual may provide the genomic building blocks for creating highly penetrant apomictic diploids and cross relatives. (og-l002.com)
• Naumova screen a relatively homogeneous setting of obligate apomictic seed development (Aliyu are uncommon and are seen as a both apomictic and intimate duplication TLN1 (Li plants display highly variable settings of seed development, from obligate sexuality, through adjustable relative degrees of intimate and apomictic seed development in specific taxa, plants and populations, to obligate apomixis. (og-l002.com)

Diploid3

• We have compared the transcriptomic profiles of microdissected live ovules at four developmental stages between a diploid sexual and diploid apomictic Boechera. (uni-konstanz.de)
• Daurelio LD, Espinoza F, Quarin CL, Pessino SC (2004) Genetic diversity in sexual diploid and apomictic tetraploid populations of Paspalum notatum situated in sympatry or allopatry. (springer.com)
• It showed a frequency of multiembryonic sacs of 29% in the ovules examined, whereas sacs were absent in the diploid type. (bvsalud.org)

Embryo7

• However, in asexually reproducing apomictic plants, the egg cell develops parthenogenetically without fertilization to produce the embryo. (plantcell.org)
• In immature ovules at the premeiotic stage, one to several companion nucellar cells surrounding the megaspore mother cell enlarge, undergo a series of mitoses, and finally differentiate into non-reduced embryo sacs termed aposporous embryo sacs (AESs). (biomedcentral.com)
• In another version, the cells of the ovule ( 2n ) develop into an embryo instead of - or in addition to - the fertilized egg. (biology-pages.info)
• fertilized egg:fertilized central cell (F:F)] are characteristic of sexual seed production in (C). However, reduced female gametes may be fertilized by unreduced apomictic sperm cells (black arrow), increasing seed embryo and endosperm ploidy. (og-l002.com)
• of an ovule , with the body completely inverted so that the micropyle area is adjacent to the funicle , the embryo sac is more or less straight. (nsw.gov.au)
• Gametophytic apomictic plants form non-reduced embryo sacs that generate clonal embryos by parthenogenesis, in the absence of both meiosis and egg-cell fertilization. (ebscohost.com)
• Development of more than one embryo from a single egg or ovule. (thefreedictionary.com)

Boechera1

• It is also the most promiscuous, having formed apomictic hybrids with at least 15 other species of Boechera . (swbiodiversity.org)

Meiotic and apomictic1

• Competition between meiotic and apomictic pathways during ovule and seed development results in clonality. (geneticsmr.com)

Female gametophyte1

• In flowering plants, the ovule contains the female gametophyte that is composed of the egg and the central, synergid, and antipodal cells ( Reiser and Fischer, 1993 ). (plantcell.org)

Seeds4

• Apomictic (without mixing): producing seeds from unfertilized ovules. (swcoloradowildflowers.com)
• Upon fertilization, these ovules develop into seeds while the gynoecium turns into a fruit. (bvsalud.org)
• In effect, apomictic seeds are clones of the parent plant, and are equivalent to vegetative propagation through seed. (yumpu.com)
• GA 3 application allowed ovules of all treated flowers to give partially developed seeds that were able to ensure sufficient support for fruit development over then 60% compared to control. (jnsciences.org)

Genes9

• Interestingly, some transduplicated segments corresponded to genes previously associated with apomictic development. (springer.com)
• In the past few years, both differential display and RNA-seq comparative approaches involving reproductive organs of sexual plants and their apomictic counterparts have yielded extensive lists of candidate genes. (biomedcentral.com)
• We have previously identified several cDNA fragments with high similarity to genes involved in RNA biology and with differential amplification between sexual and apomictic Paspalum notatum plants. (biomedcentral.com)
• Over recent years, we have identified mutations in several genes that phenocopy partially apomictic ovule development. (ird.fr)
• In this review, we present an overview of the current knowledge of the genes and hormones involved in determining ovule number and gynoecium size. (bvsalud.org)
• The established Hieracium resource represents a substantial contribution towards the investigation of early sexual and apomictic female gamete development, and the generation of new candidate genes and markers. (biomedcentral.com)
• In this study we sought to identify differentially expressed genes related to the semigamy genotype by implementing a comparative microarray analysis of anthers and ovules between a non-semigametic Pima S-1 cotton and its doubled haploid natural isogenic mutant semigametic 57-4. (ebscohost.com)
• Results: The comparative analysis between isogenic 57-4 and Pima S-1 identified 284 genes in anthers and 1,864 genes in ovules as being differentially expressed in the semigametic genotype 57-4. (ebscohost.com)
• Based on gene functions, 127 differentially expressed genes were common to both semigametic anthers and ovules, with 115 being consistently differentially expressed in both tissues. (ebscohost.com)

Ovaries1

• We have analyzed the temporal and spatial expression of cDNA sequences by in situ hybridization in ovaries of apomictic and sexual plants. (ebscohost.com)

Gene5

• By contrast, most late stage-specific tags were upregulated in the apomictic ovules, likely the result of increased gene copy number in apomictic (hexaploid) versus sexual (triploid) endosperm or of parthenogenesis. (uni-konstanz.de)
• Gene copy number estimations revealed a moderate representation of the elements in the genome, with significantly increased numbers in a sexual genotype with respect to an apomictic one. (springer.com)
• Our findings also suggest a pivotal role for this candidate gene in nucellar cell fate, as its diminished expression is correlated with initiation of the apomictic pathway in plants. (biomedcentral.com)
• Gene regulatory networks involving transcription factors and hormonal communication regulate ovule primordium initiation, spacing on the placenta, and development. (bvsalud.org)
• Understanding and fine-tuning the gene regulatory networks influencing ovule number and pistil length open up strategies for crop yield improvement, which is pivotal in light of a rapidly growing world population. (bvsalud.org)

Diploids2

• Diploids are obligate sexual, whereas polyploids are usually apomictic. (edu.pl)
• He is best known for his work with the Berkeley geneticist E. B. Babcock in ar ticulating the idea of the polyploid complex, a complex of reproductive forms centering on sexual diploids surrounded by polyploids, which may be apomictic as in Crepis, and for being the master of the synthetic review article (3). (tripod.com)

Fertilization3

• In many apomictic plants, seed development does occur without fertilization or with only partial fertilization ( 3 ). (pnas.org)
• The transition from quiescent ovule to proliferating zygote occurs after fertilization, which initiates seed development. (plantcell.org)
• CCF) Seed advancement in facultative apomicts depends upon sexual events since the meiotically derived FG and the central cell of the apomictic FG commonly require fertilization. (og-l002.com)

Differentially expressed1

• We previously isolated several transcripts representing novel sequences differentially expressed in reproductive tissues of sexual and apomictic plants. (springer.com)

Tissues2

• see Glossary, Box 1 ) gametes, respectively, form in specialized reproductive tissues of the flower: the anther and ovule ( Fig. 1 ). (biologists.org)
• While ovule development in Arabidopsis can be followed by a variety of different imaging techniques, no experimental strategy presently exists that enables an easy and straightforward investigation of the morphology of internal tissues of the ovule with cellular resolution. (biomedcentral.com)

Developmental stages2

• The protocol enables the quick and reproducible imaging of fixed Arabidopsis ovules of all developmental stages. (biomedcentral.com)
• The purpose of this work was to extend the N69 cDNA sequence and to characterize its expression at different developmental stages in both sexual and apomictic individuals. (biomedcentral.com)

Primordium1

• An individual Arabidopsis ovule primordium emerges as a finger-like protrusion emanating from the placental tissue of the gynoecium [ 6 , 7 ]. (biomedcentral.com)

Hybridization1

• Moreover, in situ hybridization observations revealed that PnTgs1-like expression is relatively higher in ovules of sexual plants throughout development, from premeiosis to maturity. (biomedcentral.com)

Endosperm1

• Agamospermous endosperm may suffer from genomic imbalance, so that nutritious ovules, which can support embryos without endosperm, may be preadapted for agamospermy. (royalsocietypublishing.org)

Arabidopsis4

• We developed a protocol for rapid and robust confocal microscopy of fixed Arabidopsis ovules of all stages. (biomedcentral.com)
• Several features of Arabidopsis ovules have facilitated genetic studies of their development, including their large number per gynoecium (around 50) and their relatively stereotypic development, allowing the thorough analysis of mutant phenotypes by easily scoring hundreds of ovules. (biomedcentral.com)
• Chromatin dynamics within young ovules of Arabidopsis. (ird.fr)
• D. Arabidopsis : histone marker in early ovule. (ird.fr)

Cultivars2

• One of these, CitRWP , is expressed at higher levels in ovules of polyembryonic cultivars. (nature.com)
• 5. Apomictic cultivars. (yumpu.com)

Anatropous2

• Dandelion ovules are anatropous, unitegmic and tenuinucellate. (edu.pl)
• The differential growth pattern of the integuments is a major determinant of the curved or anatropous shape of the mature ovule. (biomedcentral.com)

Development2

• Most heterochronic and stage-specific tags were significantly downregulated during early apomictic ovule development, and 110 were associated with reproduction. (uni-konstanz.de)
• Data from stream cytometric verification revealed both apomictic and sexual seed development. (og-l002.com)

Plants2

• The model has for the first time provided a unique tool for genetic mapping in apomictic plants. (eurekamag.com)
• A genomic and transcriptomic resource was developed for Hieracium subgenus Pilosella (Asteraceae) which incorporates characterized sexual, apomictic and mutant apomict plants exhibiting reversion to sexual reproduction. (biomedcentral.com)

Pathway2

• A fundamental contribution to the understanding of the genetic control of the apomictic pathway could be provided by a deep knowledge of molecular mechanisms that regulate the reproductive events. (deepdyve.com)
• Apomicts develop additional female gametogenic cells that suppress the sexual pathway in ovules. (biomedcentral.com)

Cassava2

• Embryonic, meiotic and molecular analysis of apomictic cassava (Manihot esculenta Crantz). (geneticsmr.com)
• This result confirms the facultative apomictic nature of cassava, with high environmental effect. (bvsalud.org)

Clones1

• Isoenzyme analysis and Southern hybridisation by mini- and microsatellite probes reveal the existence of different clones within populations of (supposedly apomictic) H. iseranum and H. piloselliflorum . (cas.cz)

Populations1

• Apomictic populations can be quite variable although apomictic families are much less variable than sexuals. (royalsocietypublishing.org)

Triploid1

• Reproductive mode: apomictic triploid. (tropicos.org)

Placenta1

• Finally, the proximal funiculus is a stalk-like structure that connects the ovule to the placenta. (biomedcentral.com)

Morphogenesis1

• For whom the BELL tolls: ovule morphogenesis and beyond. (iasprr.org)

Quantitative1

• In a complementary approach, we also explore the functional link between early ovule architecture and germ cell fate, using quantitative and live imaging combined to computational modeling. (ird.fr)

Tissue1

• Ovules arise from meristematic tissue within the gynoecium. (bvsalud.org)

Morphological1

• The ensuing polyploid type exhibits an apomictic nature and maintains its morphological characteristics in the progeny. (bvsalud.org)

Plant2

• The model was validated through computer simulation and further demonstrated for its usefulness by analyzing a real data for an apomictic woody plant. (eurekamag.com)
• The ovule is the major female plant organ involved in sexual reproduction and the progenitor of the seed. (biomedcentral.com)

Sporophytic1

• In comparison, in apospory an FM-like cell is normally generated straight from a sporophytic nucellar cell in the ovule that's at a posture not the same as that of the MMC. (og-l002.com)