Dataset Information

Kin recognition within a seed and the effect of genetic relatedness of an endosperm to its compatriot embryo on maize seed development.

ABSTRACT: As one of two sexual products resulting from double fertilization in angiosperms, the endosperm nourishes its compatriot embryo during seed development and/or germination and ultimately dies. Theoretical studies suggest that the genetic relatedness of an endosperm to its embryo in the same seed might determine the amount of resources ultimately available for the embryo during seed development. We took advantage of the phenomenon of heterofertilization in cultivated maize to empirically test whether genetic relatedness between a triploid embryo-nourishing endosperm and its compatriot diploid embryo impacts the process of resource allocation between these two sexually produced entities. We used genetically distinct maize inbred lines to perform two crossing experiments. Dry weights of dissected embryos and endosperms of mature heterofertilized and adjacent homofertilized kernels were compared. Embryo weight of heterofertilized kernels was significantly less than that of embryos of homofertilized kernels, whereas there was no significant difference in endosperm weight between the two types of kernels. Our results suggest that the degree of genetic relatedness of an endosperm to its compatriot embryo affects seed development and specifically the amount of maternal resources allocated to an endosperm that are eventually turned over to an embryo. The lower the coefficient of relatedness of an endosperm to its compatriot embryo, the smaller the embryo. Thus, the endosperm of a heterofertilized seed appears to behave less cooperatively with respect to resource transfer toward its less closely related embryo compared with the endosperm of a homofertilized seed.

SUBMITTER: Wu CC

PROVIDER: S-EPMC3568322 | biostudies-literature | 2013 Feb

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Kin recognition within a seed and the effect of genetic relatedness of an endosperm to its compatriot embryo on maize seed development.

Wu Chi-Chih CC Diggle Pamela K PK Friedman William E WE

Proceedings of the National Academy of Sciences of the United States of America 20130123 6

As one of two sexual products resulting from double fertilization in angiosperms, the endosperm nourishes its compatriot embryo during seed development and/or germination and ultimately dies. Theoretical studies suggest that the genetic relatedness of an endosperm to its embryo in the same seed might determine the amount of resources ultimately available for the embryo during seed development. We took advantage of the phenomenon of heterofertilization in cultivated maize to empirically test whet ...[more]

PMID: 23345441

Similar Datasets

Project description:Background and aimsApomixis, or asexual seed formation, in polyploid Hieracium subgenus Pilosella species results in clonal progeny with a maternal genotype. An aposporous embryo sac forms mitotically from a somatic cell, without prior meiosis, while embryo and endosperm formation is fertilization independent (autonomous). The latter two developmental components are tightly linked in Hieracium . Recently, two plants, AutE196 and AutE24, were identified from two different crosses. Both form embryo sacs via the sexual route by undergoing meiosis, and embryo development requires fertilization; however, 18 % of embryo sacs can undergo autonomous endosperm (AutE) formation. This study investigated the qualitative and quantitative inheritance of the AutE trait and factors influencing phenotype expressivity. An additional focus was to identify the linkage group bearing the AutE locus in AutE196.MethodsCrosses and cytology were used to examine the inheritance of AutE from AutE24 and AutE196, and to reintroduce apomictic components into AutE plants, thereby changing the ploidy of developing embryo sacs and increasing the dosage of AutE loci. Markers from a Hieracium apomict linkage map were examined within a backcrossed AutE196 mapping population to identify the linkage group containing the AutE196 locus.Key resultsQualitative autonomous endosperm in the AutE24 line was conferred by a single dominant locus, and the trait was transmitted through male and female gametes in AutE196 and AutE24. Expressivity of the trait did not significantly increase when AutE loci from AutE196 and AutE24 were both present in the progeny, within embryo sacs formed via apospory, or sexually derived embryo sacs with increased ploidy. It remains unclear if these are identical loci.ConclusionsThe qualitative trait of autonomous endosperm formation is conferred by single dominant loci in AutE196 and AutE24. High expressivity of autonomous endosperm formation observed in apomicts requires additional genetic factors. Potential candidates may be signals arising from fertilization-independent embryo formation.

Project description:The emergence of high-throughput, high-density genotyping methods combined with increasingly powerful computing systems has created opportunities to further discover and exploit the genes controlling agronomic performance in elite maize breeding populations. Understanding the genetic basis of population structure in an elite set of materials is an essential step in this genetic discovery process. This paper presents a genotype-based population analysis of all maize inbreds whose Plant Variety Protection certificates had expired as of the end of 2013 (283 inbreds) as well as 66 public founder inbreds. The results provide accurate population structure information and allow for important inferences in context of the historical development of North American elite commercial maize germplasm. Genotypic data was obtained via genotyping-by-sequencing on 349 inbreds. After filtering for missing data, 77,314 high-quality markers remained. The remaining missing data (average per individual was 6.22 percent) was fully imputed at an accuracy of 83 percent. Calculation of linkage disequilibrium revealed that the average r2 of 0.20 occurs at approximately 1.1 Kb. Results of population genetics analyses agree with previously published studies that divide North American maize germplasm into three heterotic groups: Stiff Stalk, Non-Stiff Stalk, and Iodent. Principal component analysis shows that population differentiation is indeed very complex and present at many levels, yet confirms that division into three main sub-groups is optimal for population description. Clustering based on Nei's genetic distance provides an additional empirical representation of the three main heterotic groups. Overall fixation index (FST), indicating the degree of genetic divergence between the three main heterotic groups, was 0.1361. Understanding the genetic relationships and population differentiation of elite germplasm may help breeders to maintain and potentially increase the rate of genetic gain, resulting in higher overall agronomic performance.

Project description:BackgroundWheat embryo and endosperm play important roles in seed germination, seedling survival, and subsequent vegetative growth. ABA can positively regulate dormancy induction and negatively regulates seed germination at low concentrations, while low H2O2 concentrations promote seed germination of cereal plants. In this report, we performed the first integrative transcriptome analysis of wheat embryo and endosperm responses to ABA and H2O2 stresses.ResultsWe used the GeneChip® Wheat Genome Array to conduct a comparative transcriptome microarray analysis of the embryo and endosperm of elite Chinese bread wheat cultivar Zhengmai 9023 in response to ABA and H2O2 treatments during seed germination. Transcriptome profiling showed that after H2O2 and ABA treatments, the 64 differentially expressed genes in the embryo were closely related to DNA synthesis, CHO metabolism, hormone metabolism, and protein degradation, while 121 in the endosperm were involved mainly in storage reserves, transport, biotic and abiotic stresses, hormone metabolism, cell wall metabolism, signaling, and development. Scatter plot analysis showed that ABA treatment increased the similarity of regulated patterns between the two tissues, whereas H2O2 treatment decreased the global expression similarity. MapMan analysis provided a global view of changes in several important metabolism pathways (e.g., energy reserves mobilization, cell wall metabolism, and photosynthesis), as well as related functional groups (e.g., cellular processes, hormones, and signaling and transport) in the embryo and endosperm following exposure of seeds to ABA and H2O2 treatments during germination. Quantitative RT-PCR analysis was used to validate the expression patterns of nine differentially expressed genes.ConclusionsWheat seed germination involves regulation of a large number of genes involved in many functional groups. ABA/H2O2 can repress/promote seed germination by coordinately regulating related gene expression. Our results provide novel insights into the transcriptional regulation mechanisms of embryo and endosperm in response to ABA and H2O2 treatments during seed germination.

Dataset Information

Kin recognition within a seed and the effect of genetic relatedness of an endosperm to its compatriot embryo on maize seed development.

Publications

Kin recognition within a seed and the effect of genetic relatedness of an endosperm to its compatriot embryo on maize seed development.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets