The co-expression of genes involved in seed coat and endosperm development promotes seed abortion in grapevine

Abstract Background Seeds of Paeonia ostii have been proposed as a source of raw material for the production of edible oil; however, lack of information about the developmental biology of the seeds hampers our ability to use them. Our aim was to investigate development of the seed coat, endosperm and embryo of P. ostii in relation to timing of accumulation of nutrient reserves from pollination to seed maturity. Ovules and developing seeds of P. ostii were collected at various stages of development from zygote to maturity. Seed fresh mass, dry mass, germination, moisture, soluble sugars, starch, protein and oil content were determined. Ontogeny of seeds including embryo, endosperm and seed coat were analyzed histologically. Results The ovule of P. ostii is anatropous, crassinucellate and bitegmic. The zygote begins to divide at about 5 days after pollination (DAP), and the division is not accompanied by cell wall formation. By 25 DAP, the proembryo begins to cellularize. Thereafter, several embryo primordia appear at the surface of the cellularized proembryo, but only one matures. Endosperm development follows the typical nuclear type. The seed coat is derived from the outer integument. During seed development, soluble sugars, starch and crude fat content increased and then decreased, with maximum contents at 60, 80 and 100 DAP, respectively. Protein content was relatively low compared with soluble sugars and crude fat, but it increased throughout seed development. Conclusions During seed development in P. ostii, the seed coat acts as a temporary storage tissue. Embryo development of P. ostii can be divided into two stages: a coenocytic proembryo from zygote (n + n) that degenerates and a somatic embryo from peripheral cells of the proembryo (2n → 2n). This pattern of embryogeny differs from that of all other angiosperms, but it is similar to that of gymnosperms.

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Embriología de Erythroxylum havanense Jacq. (Erythroxylaceae)

Botanical Sciences ◽

10.17129/botsci.1503 ◽

2017 ◽

pp. 25

Author(s):

Sonia Vázquez-Santana ◽

César A. Domínguez ◽

Judith Márquez-Guzmán

Keyword(s):

Seed Coat ◽

Embryo Sac ◽

Pollen Grains ◽

Endosperm Development ◽

Anther Wall ◽

Starch Grains ◽

Reproductive Structures ◽

Exine Sculpturing ◽

Erythroxylum Havanense ◽

Mature Anther

We studied the development of reproductive structures in pin and thrum morphs of Erythroxylum havanense. The young anther wall consists of an epidermis, endothecium , 1-3 middle layers anda binucleate secretory tapetum. The mature anther wall has only two layers: epidermis and endothecium. Microspore tetrads are tetrahedral or isobilateral. Mature pollen grains are tricolporate, bicellular and contain starch grains. Exine sculpturing is verrugate in thrum pollen and reticulate in pin pollen. The ovule is sessile, pendulous, anatropous, bitegmic and crassinucellate. The embryo sac is heptacellular. An endothelium is differentiated. The endosperm development is nuclear, and the basal part of the nucellus persists during early endosperm development. Both integuments form the seed coat.

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Gametophytic expression of genes controlling endosperm development in maize

Theoretical and Applied Genetics ◽

10.1007/bf00303961 ◽

1988 ◽

Vol 75 (2) ◽

pp. 252-258 ◽

Cited By ~ 17

Author(s):

E. Ottaviano ◽

D. Petroni ◽

M. E. Pe′

Keyword(s):

Endosperm Development ◽

Expression Of Genes

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Post-Zygotic Seed Abortion in Sexual Diploid × Apomictic Tetraploid Intraspecific Paspalum Crosses

Australian Journal of Botany ◽

10.1071/bt9940449 ◽

1994 ◽

Vol 42 (4) ◽

pp. 449 ◽

Cited By ~ 17

Author(s):

GA Norrmann ◽

OA Bovo ◽

CL Quarin

Keyword(s):

Pollen Tube ◽

Success Rate ◽

Pollen Tube Growth ◽

Endosperm Development ◽

Tube Growth ◽

Seed Abortion ◽

Self Incompatibility ◽

Incompatible Pollen ◽

Incompatibility System

In many species of Paspalum, diploid (2x) cytotypes are usually outbreeders due to a self incompatibility system, while tetraploid (4x) conspecific counterparts are pseudogamous self-fertile apomicts. Intraspecific crossability between 2x female and 4x male cytotypes was investigated using classical methods of crossing in P. almum, P. brunneum, P. rufum, P. intermedium and P. quadrifarium. Expected triploid BII hybrids were obtained in P. intermedium (crossability: 0.004%) and in P. brunneum (crossability: 0.015%). In P. rufum, only tetraploid BIII hybrids were achieved with a crossability of 0.025% Looking for a better performance, in vitro ovary rescue was attempted 5 days after pollination in intraspecific 2x × 4x crosses of P. almum, P. quadrifarium, P. intermedium and P. rufum. The method was useful to recover some triploid BII hybrids in P. almum (success rate: 0.49%) and in P. rufum (0.59%), but failed in P. intermedium and P. quadrifarium. Pollen tube growth was usually inhibited at the stigma or style levels after self-pollination in 2x plants, confirming that diploids are self-incompatible. Pollen of 4x cytotypes germinated and penetrated the pistils of diploid conspecific cytotypes. This indicated that no incompatibility system exists in these species to keep the 2x cytotypes from hybridising with 4x conspecific cytotypes as pollen donors. However, after pollination of 2x cytotypes with pollen of 4x counterparts, most ovules showed embryo and endosperm development, but a few days later, endosperms collapsed and embryos stopped their development. As a result of these processes, sexual self-incompatible 2x cytotypes of Paspalum species produced very few triploid hybrids when pollinated with pollen of their apomictic 4x counterparts. Thus, the low diploid-tetraploid crossability was due to the existence of a post-zygotic abortive system and not caused by pre-fertilisation barriers.

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Auxin production in the endosperm drives seed coat development in Arabidopsis

eLife ◽

10.7554/elife.20542 ◽

2016 ◽

Vol 5 ◽

Cited By ~ 70

Author(s):

Duarte D Figueiredo ◽

Rita A Batista ◽

Pawel J Roszak ◽

Lars Hennig ◽

Claudia Köhler

Keyword(s):

Transcription Factor ◽

Seed Coat ◽

Auxin Transport ◽

Flowering Plants ◽

Polycomb Group ◽

Sperm Cells ◽

Seed Abortion ◽

Mads Box ◽

Auxin Production ◽

Epigenetic Regulators

In flowering plants, seed development is initiated by the fusion of the maternal egg and central cells with two paternal sperm cells, leading to the formation of embryo and endosperm, respectively. The fertilization products are surrounded by the maternally derived seed coat, whose development prior to fertilization is blocked by epigenetic regulators belonging to the Polycomb Group (PcG) protein family. Here we show that fertilization of the central cell results in the production of auxin and most likely its export to the maternal tissues, which drives seed coat development by removing PcG function. We furthermore show that mutants for the MADS-box transcription factor AGL62 have an impaired transport of auxin from the endosperm to the integuments, which results in seed abortion. We propose that AGL62 regulates auxin transport from the endosperm to the integuments, leading to the removal of the PcG block on seed coat development.

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SGlu2 gene expression in coats of soybean seeds

Journal of Seed Science ◽

10.1590/2317-1545v36n3977 ◽

2014 ◽

Vol 36 (3) ◽

pp. 290-294

Author(s):

Carlos André Bahry ◽

Paulo Dejalma Zimmer

Keyword(s):

Gene Expression ◽

Seed Coat ◽

Soybean Seed ◽

Biotic Factors ◽

Yellow Seed ◽

Development Stages ◽

Expression Of Genes ◽

Genes Encoding ◽

Soybean Genotypes ◽

Seed Coats

Glucanases can act in plant defense against biotic factors. Despite its importance, research to study the expression of genes encoding glucanases in soybean seed coats is limited. The aim of this study was to assess the relative expression of the SGlu2 gene (β-1.3-Glucanase 2), possibly involved in defense against biotic factors, in coats of seeds of four soybean genotypes. Two genotypes of black seed coats, IAC and TP, and two of yellow seed coats, BMX Potência RR and CD 202 were used. Seeds were multiplied in a greenhouse at Embrapa Clima Temperado - ETB, and the gene expression assay was performed at the Laboratório de Sementes e Biotecnologia, UFPel. Seed coat gene expression was assessed by qPCR technique in four development stages: 40, 45, 50 and 55 days after anthesis. The SGlu2 gene shows more expression in the BMX Potência RR genotype compared to other genotypes. The gene expression in the seed coat is constant in different development stages of CD 202 cultivar and IAC and TP strains, except at 45 DAA (days after application) for this latter genotype.

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Diversity of metabolite accumulation patterns in inner and outer seed coats of pomegranate: exploring their relationship with genetic mechanisms of seed coat development

Horticulture Research ◽

10.1038/s41438-019-0233-4 ◽

2020 ◽

Vol 7 (1) ◽

Cited By ~ 5

Author(s):

Gaihua Qin ◽

Chunyan Liu ◽

Jiyu Li ◽

Yongjie Qi ◽

Zhenghui Gao ◽

...

Keyword(s):

Seed Coat ◽

Developmental Stages ◽

Morphological Differentiation ◽

Expression Of Genes ◽

Monolignol Biosynthesis ◽

Genes Encoding ◽

Genetic Mechanisms ◽

Sensory Qualities ◽

Pomegranate Seeds ◽

Seed Coats

AbstractThe expanded outer seed coat and the rigid inner seed coat of pomegranate seeds, both affect the sensory qualities of the fruit and its acceptability to consumers. Pomegranate seeds are also an appealing model for the study of seed coat differentiation and development. We conducted nontarget metabolic profiling to detect metabolites that contribute to the morphological differentiation of the seed coats along with transcriptomic profiling to unravel the genetic mechanisms underlying this process. Comparisons of metabolites in the lignin biosynthetic pathway accumulating in seed coat layers at different developmental stages revealed that monolignols, including coniferyl alcohol and sinapyl alcohol, greatly accumulated in inner seed coats and monolignol glucosides greatly accumulated in outer seed coats. Strong expression of genes involved in monolignol biosynthesis and transport might explain the spatial patterns of biosynthesis and accumulation of these metabolites. Hemicellulose constituents and flavonoids in particular accumulated in the inner seed coat, and candidate genes that might be involved in their accumulation were also identified. Genes encoding transcription factors regulating monolignol, cellulose, and hemicellulose metabolism were chosen by coexpression analysis. These results provide insights into metabolic factors influencing seed coat differentiation and a reference for studying seed coat developmental biology and pomegranate genetic improvement.

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How is embryo size genetically regulated in rice?

Development ◽

10.1242/dev.122.7.2051 ◽

1996 ◽

Vol 122 (7) ◽

pp. 2051-2058 ◽

Cited By ~ 1

Author(s):

S.K. Hong ◽

H. Kitano ◽

H. Satoh ◽

Y. Nagato

Keyword(s):

Double Mutant ◽

Postembryonic Development ◽

Endosperm Development ◽

The Other ◽

Single Locus ◽

Mutant Analysis ◽

Embryo Size ◽

Recessive Mutations ◽

Expression Of Genes ◽

Giant Embryo

It is unclear how embryo size is genetically regulated in plants. Since cereals have a large persisting endosperm, it is expected that embryo size is affected by endosperm development. Nine single recessive mutations, four reduced embryo mutations representing three loci, REDUCED EMBRYO1, REDUCED EMBRYO2 and REDUCED EMBRYO3, four giant embryo mutations derived from a single locus GIANT EMBRYO, and one endospermless mutation endospermless1-2 were analyzed. Every reduced embryo mutation caused reduction of all the embryonic organs including apical meristems and the enlargement of the endosperm. The giant embryo mutants have a reduced endosperm and an enlarged scutellum. However, shoot and radicle sizes were not affected. All the reduced embryo and giant embryo mutations did not largely affect postembryonic development. Accordingly, the expression of genes analyzed are seed-specific. In reduced embryo and giant embryo mutations, abnormalities were detected in both embryo and endosperm as early as 2 days after pollination. endospermless1-1 resulted in an early loss of endosperm, yielding a giant embryo, suggesting that embryo growth was physically limited by the endosperm. A double mutant between giant embryo-2 and club-shaped embryo1-1, which has a normal endosperm and a minute undifferentiated embryo, resulted in a club-shaped embryo1-1 embryo and a reduced endosperm of giant embryo-2, indicating that GIANT EMBRYO regulates the endosperm development. Double mutants between giant embryo-2 and three reduced embryo mutants exhibited the reduced embryo phenotype in both embryo and endosperm, suggesting that reduced embryo mutations cause the enlarged endosperm. Further, a double mutant of reduced embryo3 and endospermless1-1 showed the enlarged embryo in endospermless seed. This confirms that reduced embryo3 does not regulate embryo size but enlarges endosperm size. Together with the results of the other double mutant analysis, REDUCED EMBRYO1, REDUCED EMBRYO2, REDUCED EMBRYO3 and GIANT EMBRYO are concluded to regulate endosperm development.

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RH17 restricts reproductive fate and represses autonomous seed coat development in sexual Arabidopsis

Development ◽

10.1242/dev.198739 ◽

2021 ◽

Vol 148 (19) ◽

Author(s):

Ron Eric Stein ◽

Berit Helge Nauerth ◽

Laura Binmöller ◽

Luise Zühl ◽

Anna Loreth ◽

...

Keyword(s):

Seed Coat ◽

Reproductive Development ◽

Female Flower ◽

Endosperm Development ◽

Regulatory Control ◽

Single Mutation ◽

Rna Helicases ◽

Germline Development ◽

Sexual And Asexual Reproduction ◽

Agricultural Applications

ABSTRACT Plant sexual and asexual reproduction through seeds (apomixis) is tightly controlled by complex gene regulatory programs, which are not yet fully understood. Recent findings suggest that RNA helicases are required for plant germline development. This resembles their crucial roles in animals, where they are involved in controlling gene activity and the maintenance of genome integrity. Here, we identified previously unknown roles of Arabidopsis RH17 during reproductive development. Interestingly, RH17 is involved in repression of reproductive fate and of elements of seed development in the absence of fertilization. In lines carrying a mutant rh17 allele, development of supernumerary reproductive cell lineages in the female flower tissues (ovules) was observed, occasionally leading to formation of two embryos per seed. Furthermore, seed coat, and putatively also endosperm development, frequently initiated autonomously. Such induction of several features phenocopying distinct elements of apomixis by a single mutation is unusual and suggests that RH17 acts in regulatory control of plant reproductive development. Furthermore, an in-depth understanding of its action might be of use for agricultural applications.

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Overexpression of an ethylene-forming ACC oxidase (ACO) gene precedes the Minute Hilum seed coat phenotype in Glycine max

BMC Genomics ◽

10.1186/s12864-020-07130-8 ◽

2020 ◽

Vol 21 (1) ◽

Author(s):

Gracia Zabala ◽

Anupreet Kour ◽

Lila O. Vodkin

Keyword(s):

Seed Coat ◽

Developmental Stages ◽

Sequence Data ◽

Acc Oxidase ◽

Germplasm Collection ◽

Cdna Libraries ◽

Small Ring ◽

Recurrent Parent ◽

Expression Of Genes ◽

Hormone Balance

Abstract Background To elucidate features of seed development, we investigated the transcriptome of a soybean isoline from the germplasm collection that contained an introgressed allele known as minute hilum (mi) which confers a smaller hilum region where the seed attaches to the pod and also results in seed coat cracking surrounding the hilum region. Results RNAs were extracted from immature seed from an extended hilum region (i.e., the hilum and a small ring of tissue surrounding the hilum in which the cracks form) at three different developmental stages:10–25, 25–50 and 50–100 mg seed fresh weight in two independent replicates for each stage. The transcriptomes of these samples from both the Clark isoline containing the mi allele (PI 547628, UC413, iiR t mi G), and its recurrent Clark 63 parent isoline (PI 548532, UC7, iiR T Mi g), which was used for six generations of backcrossing, were compared for differential expression of 88,648 Glyma models of the soybean genome Wm82.a2. The RNA sequence data obtained from the 12 cDNA libraries were subjected to padj value < 0.05 and at least two-fold expression differences to select with confidence genes differentially expressed in the hilum-containing tissue of the seed coat between the two lines. Glyma.09G008400 annotated as encoding an ethylene forming enzyme, ACC oxidase (ACO), was found to be highly overexpressed in the mi hilum region at 165 RPKMs (reads per kilobase per million mapped reads) compared to the standard line at just 0.03 RPKMs. Evidence of changes in expression of genes downstream of the ethylene pathway included those involved in auxin and gibberellin hormone action and extensive differences in expression of cell wall protein genes. These changes are postulated to determine the restricted hilum size and cracking phenotypes. Conclusions We present transcriptome and phenotypic evidence that substantially higher expression of an ethylene-forming ACO gene likely shifts hormone balance and sets in motion downstream changes resulting in a smaller hilum phenotype and the cracks observed in the minute hilum (mi) isoline as compared to its recurrent parent.

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