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Dusi DMA, Alves ER, Cabral GB, Mello LV, Rigden DJ, Silveira ÉD, Alves-Ferreira M, Guimarães LA, Gomes ACMM, Rodrigues JCM, Carneiro VTC. An exonuclease V homologue is expressed predominantly during early megasporogenesis in apomictic Brachiaria brizantha. PLANTA 2023; 258:5. [PMID: 37219749 DOI: 10.1007/s00425-023-04162-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Accepted: 05/15/2023] [Indexed: 05/24/2023]
Abstract
MAIN CONCLUSION An exonuclease V homologue from apomictic Brachiaria brizantha is expressed and localized in nucellar cells at key moments when these cells differentiate to give rise to unreduced gametophytes. Brachiaria is a genus of forage grasses with economical and agricultural importance to Brazil. Brachiaria reproduces by aposporic apomixis, in which unreduced embryo sacs, derived from nucellar cells, other than the megaspore mother cell (MMC), are formed. The unreduced embryo sacs produce an embryo without fertilization resulting in clones of the mother plant. Comparative gene expression analysis in ovaries of sexual and apomictic Brachiaria spp. revealed a sequence from B. brizantha that showed a distinct pattern of expression in ovaries of sexual and apomictic plants. In this work, we describe a gene named BbrizExoV with strong identity to exonuclease V (Exo V) genes from other grasses. Sequence analysis in signal prediction tools showed that BbrizExoV might have dual localization, depending on the translation point. A longer form to the nucleus and a shorter form which would be directed to the chloroplast. This is also the case for monocot sequences analyzed from other species. The long form of BbrizExoV protein localizes to the nucleus of onion epidermal cells. Analysis of ExoV proteins from dicot species, with exception of Arabidopsis thaliana ExoVL protein, showed only one localization. Using a template-based AlphaFold 2 modelling approach the structure of BbrizExoV in complex with metal and ssDNA was predicted based on the holo structure of the human counterpart. Features predicted to define ssDNA binding but a lack of sequence specificity are shared between the human enzyme and BbrizExoV. Expression analyses indicated the precise site and timing of transcript accumulation during ovule development, which coincides with the differentiation of nucelar cells to form the typical aposporic four-celled unreduced gametophyte. A putative function for this protein is proposed based on its homology and expression pattern.
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Affiliation(s)
- Diva M A Dusi
- Brazilian Agricultural Research Corporation (Embrapa), Embrapa Genetic Resources and Biotechnology, Cx. Postal 02372, Brasilia, DF, 70770-917, Brazil
| | - Elizângela R Alves
- Brazilian Agricultural Research Corporation (Embrapa), Embrapa Genetic Resources and Biotechnology, Cx. Postal 02372, Brasilia, DF, 70770-917, Brazil
- Department of Celular Biology, University of Brasilia, Brasília, DF, 70910-900, Brazil
| | - Gláucia B Cabral
- Brazilian Agricultural Research Corporation (Embrapa), Embrapa Genetic Resources and Biotechnology, Cx. Postal 02372, Brasilia, DF, 70770-917, Brazil
| | - Luciane V Mello
- School of Life Sciences, University of Liverpool, Crown St, Liverpool, L69 7ZB, UK
| | - Daniel J Rigden
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Crown St, Liverpool, L69 7ZB, UK
| | - Érica D Silveira
- Brazilian Agricultural Research Corporation (Embrapa), Embrapa Genetic Resources and Biotechnology, Cx. Postal 02372, Brasilia, DF, 70770-917, Brazil
- Department of Genetics, Universidade Federal do Rio de Janeiro, Av. Prof. Rodolpho Paulo Rocco, s/n Prédio do CCS Instituto de Biologia, Rio de Janeiro, RJ, Brazil
| | - Márcio Alves-Ferreira
- Department of Genetics, Universidade Federal do Rio de Janeiro, Av. Prof. Rodolpho Paulo Rocco, s/n Prédio do CCS Instituto de Biologia, Rio de Janeiro, RJ, Brazil
| | - Larissa A Guimarães
- Brazilian Agricultural Research Corporation (Embrapa), Embrapa Genetic Resources and Biotechnology, Cx. Postal 02372, Brasilia, DF, 70770-917, Brazil
- Department of Celular Biology, University of Brasilia, Brasília, DF, 70910-900, Brazil
| | - Ana Cristina M M Gomes
- Brazilian Agricultural Research Corporation (Embrapa), Embrapa Genetic Resources and Biotechnology, Cx. Postal 02372, Brasilia, DF, 70770-917, Brazil
| | - Júlio C M Rodrigues
- Brazilian Agricultural Research Corporation (Embrapa), Embrapa Genetic Resources and Biotechnology, Cx. Postal 02372, Brasilia, DF, 70770-917, Brazil.
| | - Vera T C Carneiro
- Brazilian Agricultural Research Corporation (Embrapa), Embrapa Genetic Resources and Biotechnology, Cx. Postal 02372, Brasilia, DF, 70770-917, Brazil.
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Koehler AD, Rossi ML, Carneiro VTC, Cabral GB, Martinelli AP, Dusi DMA. Anther development in Brachiaria brizantha (syn. Urochloa brizantha) and perspective for microspore in vitro culture. PROTOPLASMA 2023; 260:571-587. [PMID: 35947212 DOI: 10.1007/s00709-022-01802-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Accepted: 07/31/2022] [Indexed: 06/15/2023]
Abstract
Brachiaria, a genus from the Poaceae family, is largely cultivated as forage in Brazil. Among the most cultivated varieties of Brachiaria spp., B. brizantha cv. Marandu (syn. Urochloa brizantha) is of great agronomical importance due to the large areas cultivated with this species. This cultivar is apomictic and tetraploid. Sexual diploid genotype is available for this species. The difference in levels of ploidy among sexual and apomictic plants contributes to hindering Brachiaria breeding programs. The induction of haploids and double haploids is of great interest for the generation of new genotypes with potential use in intraspecific crosses. A key factor for the success of this technique is identifying adequate microspore developmental stages for efficient embryogenesis induction. Knowledge of the morphological changes during microsporogenesis and microgametogenesis and sporophytic tissues composing the anther is critical for identifying the stages in which microspores present a higher potential for embryogenic callus and somatic embryo through in vitro culture. In this work, morphological markers were associated with anther and pollen grain developmental stages, through histological analysis. Anther development was divided into 11 stages using morphological and cytological characteristics, from anther with archesporial cells to anther dehiscence. The morphological characteristics of each stage are presented. In addition, the response of stage 8 anthers to in vitro culture indicates microspores initiating somatic embryogenic pathway.
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Affiliation(s)
- Andréa D Koehler
- University of Sao Paulo, CENA, Av. Centenario 303, Piracicaba, SP, 13416-903, Brazil
- Brazilian Agricultural Research Corporation (Embrapa), Embrapa Genetic Resources and Biotechnology, Cx.Postal 02372, Brasilia, DF, 70.770-917, Brazil
| | - Mônica L Rossi
- University of Sao Paulo, CENA, Av. Centenario 303, Piracicaba, SP, 13416-903, Brazil
| | - Vera T C Carneiro
- Brazilian Agricultural Research Corporation (Embrapa), Embrapa Genetic Resources and Biotechnology, Cx.Postal 02372, Brasilia, DF, 70.770-917, Brazil
| | - Glaucia B Cabral
- Brazilian Agricultural Research Corporation (Embrapa), Embrapa Genetic Resources and Biotechnology, Cx.Postal 02372, Brasilia, DF, 70.770-917, Brazil
| | - Adriana P Martinelli
- University of Sao Paulo, CENA, Av. Centenario 303, Piracicaba, SP, 13416-903, Brazil
| | - Diva M A Dusi
- Brazilian Agricultural Research Corporation (Embrapa), Embrapa Genetic Resources and Biotechnology, Cx.Postal 02372, Brasilia, DF, 70.770-917, Brazil.
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da Silveira SR, Koehler AD, Mendes Gomes ACM, Cabral GB, de Campos Carneiro VT, de Alencar Dusi DM, Martinelli AP. Somatic Embryogenesis of Brachiaria brizantha (Syn. Urochloa brizantha) Analyzed by In Situ Hybridization. Methods Mol Biol 2022; 2527:247-263. [PMID: 35951196 DOI: 10.1007/978-1-0716-2485-2_18] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
In situ hybridization with mRNA probes enables the detection and localization of gene expression in plant somatic embryogenesis samples. BbrizSERK is a gene that is expressed in embryogenic cells and tissues of Brachiaria. Here we describe methods used for in situ hybridization to localize BbrizSERK transcripts during somatic embryogenesis of Brachiaria brizantha according to the plant material and observations intended, using paraffin or butyl methyl methacrylate resin-embedded samples, as well as a method for whole-mount preparation applicable for the analysis of other genes involved in embryogenic processes, along with other in vitro processes.
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Affiliation(s)
- Sylvia Rodrigues da Silveira
- Plant Biotechnology Lab, Center of Nuclear Energy in Agriculture, University of São Paulo, Piracicaba, SP, Brazil
| | - Andréa Dias Koehler
- Plant Biotechnology Lab, Center of Nuclear Energy in Agriculture, University of São Paulo, Piracicaba, SP, Brazil
| | - Ana Cristina M Mendes Gomes
- Brazilian Agricultural Research Corporation (Embrapa), Embrapa Genetic Resources and Biotechnology, Brasilia, DF, Brazil
| | - Glaucia Barbosa Cabral
- Brazilian Agricultural Research Corporation (Embrapa), Embrapa Genetic Resources and Biotechnology, Brasilia, DF, Brazil
| | | | - Diva Maria de Alencar Dusi
- Brazilian Agricultural Research Corporation (Embrapa), Embrapa Genetic Resources and Biotechnology, Brasilia, DF, Brazil.
| | - Adriana Pinheiro Martinelli
- Plant Biotechnology Lab, Center of Nuclear Energy in Agriculture, University of São Paulo, Piracicaba, SP, Brazil.
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Ferreira RCU, da Costa Lima Moraes A, Chiari L, Simeão RM, Vigna BBZ, de Souza AP. An Overview of the Genetics and Genomics of the Urochloa Species Most Commonly Used in Pastures. FRONTIERS IN PLANT SCIENCE 2021; 12:770461. [PMID: 34966402 PMCID: PMC8710810 DOI: 10.3389/fpls.2021.770461] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Accepted: 11/17/2021] [Indexed: 06/14/2023]
Abstract
Pastures based on perennial monocotyledonous plants are the principal source of nutrition for ruminant livestock in tropical and subtropical areas across the globe. The Urochloa genus comprises important species used in pastures, and these mainly include Urochloa brizantha, Urochloa decumbens, Urochloa humidicola, and Urochloa ruziziensis. Despite their economic relevance, there is an absence of genomic-level information for these species, and this lack is mainly due to genomic complexity, including polyploidy, high heterozygosity, and genomes with a high repeat content, which hinders advances in molecular approaches to genetic improvement. Next-generation sequencing techniques have enabled the recent release of reference genomes, genetic linkage maps, and transcriptome sequences, and this information helps improve our understanding of the genetic architecture and molecular mechanisms involved in relevant traits, such as the apomictic reproductive mode. However, more concerted research efforts are still needed to characterize germplasm resources and identify molecular markers and genes associated with target traits. In addition, the implementation of genomic selection and gene editing is needed to reduce the breeding time and expenditure. In this review, we highlight the importance and characteristics of the four main species of Urochloa used in pastures and discuss the current findings from genetic and genomic studies and research gaps that should be addressed in future research.
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Affiliation(s)
| | - Aline da Costa Lima Moraes
- Center for Molecular Biology and Genetic Engineering (CBMEG), University of Campinas (UNICAMP), Campinas, Brazil
| | - Lucimara Chiari
- Embrapa Gado de Corte, Brazilian Agricultural Research Corporation, Campo Grande, Brazil
| | - Rosangela Maria Simeão
- Embrapa Gado de Corte, Brazilian Agricultural Research Corporation, Campo Grande, Brazil
| | | | - Anete Pereira de Souza
- Center for Molecular Biology and Genetic Engineering (CBMEG), University of Campinas (UNICAMP), Campinas, Brazil
- Department of Plant Biology, Biology Institute, University of Campinas (UNICAMP), Campinas, Brazil
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Koehler AD, Irsigler AST, Carneiro VTC, Cabral GB, Rodrigues JCM, Gomes ACMM, Togawa RC, Costa MMC, Martinelli AP, Dusi DMDA. SERK genes identification and expression analysis during somatic embryogenesis and sporogenesis of sexual and apomictic Brachiaria brizantha (Syn. Urochloa brizantha). PLANTA 2020; 252:39. [PMID: 32797317 DOI: 10.1007/s00425-020-03443-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2020] [Accepted: 08/07/2020] [Indexed: 06/11/2023]
Abstract
In Brachiaria brizantha BbrizSERK1, BbrizSERK2 and BbrizSERK3 were identified. SERK expression marks somatic embryogenesis, sexual MMC, and sexual and apomictic PMC. BbrizSERK3 might have a regulatory role in reproductive development. Somatic embryogenesis receptor-like kinase (SERK) consists of plasma membrane receptor genes that have been characterized in various species, associated with several aspects of plant development, including reproduction. SERK genes are involved in anther development and in early embryo development in sexual and asexual seed formation. To comprehend the complexity of the SERK genes and their function in Brachiaria reproduction, we performed a homology-based search in a genomic database of a sexual B. brizantha and identified sequences of three SERK genes, BbrizSERK1, BbrizSERK2, and BbrizSERK3. RNASeq data showed equivalent abundance of BbrizSERK1 and BbrizSERK2 transcripts in ovaries at early megasporogenesis of sexuals and apomicts, while BbrizSERK3 transcripts were more abundant in ovaries of sexuals than in apomicts. BbrizSERK3 results in three coding sequences due to alternative splicing, among them Variant 1 results in a protein with all the predicted domains of a SERK. BbrizSERK transcripts were detected in male reproductive tissues of both sexual and apomictic plants, suggesting a role in controlling anther development. BbrizSERK transcripts were detected early in ovule development, in the integuments, and in the megaspore mother cell of the sexual plant, but not in the cells that give rise to apomictic embryo sacs, suggesting a role in female reproductive development of sexuals. This paper provides evidences that SERK genes plays a role in the onset and establishment of somatic embryogenesis and in the reproductive development of B. brizantha and suggests a distinct role of BbrizSERK in apomixis initiation.
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Affiliation(s)
- Andréa D Koehler
- University of Sao Paulo, CENA, Av. Centenario 303, Piracicaba, SP, 13416-903, Brazil
- Brazilian Agricultural Research Corporation (Embrapa), Embrapa Genetic Resources and Biotechnology, Cx.Postal 02372, Brasília, DF, 70770-917, Brazil
- , Linhares, Brazil
| | - André S T Irsigler
- Brazilian Agricultural Research Corporation (Embrapa), Embrapa Genetic Resources and Biotechnology, Cx.Postal 02372, Brasília, DF, 70770-917, Brazil
| | - Vera T C Carneiro
- Brazilian Agricultural Research Corporation (Embrapa), Embrapa Genetic Resources and Biotechnology, Cx.Postal 02372, Brasília, DF, 70770-917, Brazil
| | - Glaucia B Cabral
- Brazilian Agricultural Research Corporation (Embrapa), Embrapa Genetic Resources and Biotechnology, Cx.Postal 02372, Brasília, DF, 70770-917, Brazil
| | - Júlio C M Rodrigues
- Brazilian Agricultural Research Corporation (Embrapa), Embrapa Genetic Resources and Biotechnology, Cx.Postal 02372, Brasília, DF, 70770-917, Brazil
| | - Ana Cristina M M Gomes
- Brazilian Agricultural Research Corporation (Embrapa), Embrapa Genetic Resources and Biotechnology, Cx.Postal 02372, Brasília, DF, 70770-917, Brazil
| | - Roberto C Togawa
- Brazilian Agricultural Research Corporation (Embrapa), Embrapa Genetic Resources and Biotechnology, Cx.Postal 02372, Brasília, DF, 70770-917, Brazil
| | - Marcos M C Costa
- Brazilian Agricultural Research Corporation (Embrapa), Embrapa Genetic Resources and Biotechnology, Cx.Postal 02372, Brasília, DF, 70770-917, Brazil
| | | | - Diva Maria de Alencar Dusi
- Brazilian Agricultural Research Corporation (Embrapa), Embrapa Genetic Resources and Biotechnology, Cx.Postal 02372, Brasília, DF, 70770-917, Brazil.
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6
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Ferreira LG, de Alencar Dusi DM, Irsigler AST, Gomes ACMM, Mendes MA, Colombo L, de Campos Carneiro VT. GID1 expression is associated with ovule development of sexual and apomictic plants. PLANT CELL REPORTS 2018; 37:293-306. [PMID: 29080908 DOI: 10.1007/s00299-017-2230-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Accepted: 10/18/2017] [Indexed: 06/07/2023]
Abstract
BbrizGID1 is expressed in the nucellus of apomictic Brachiaria brizantha, previous to aposporous initial differentiation. AtGID1a overexpression triggers differentiation of Arabidopsis thaliana MMC-like cells, suggesting its involvement in ovule development. GIBBERELLIN-INSENSITIVE DWARF1 (GID1) is a gibberellin receptor previously identified in plants and associated with reproductive development, including ovule formation. In this work, we characterized the Brachiaria brizantha GID1 gene (BbrizGID1). BbrizGID1 showed up to 92% similarity to GID1-like gibberellin receptors of other plants of the Poaceae family and around 58% to GID1-like gibberellin receptors of Arabidopsis thaliana. BbrizGID1 was more expressed in ovaries at megasporogenesis than in ovaries at megagametogenesis of both sexual and apomictic plants. In ovules, BbrizGID1 transcripts were detected in the megaspore mother cell (MMC) of sexual and apomictic B. brizantha. Only in the apomictic plants, expression was also observed in the surrounding nucellar cells, a region in which aposporous initial cells differentiate to form the aposporic embryo sac. AtGID1a ectopic expression in Arabidopsis determines the formation of MMC-like cells in the nucellus, close to the MMC, that did not own MMC identity. Our results suggest that GID1 might be involved in the proper differentiation of a single MMC during ovule development and provide valuable information on the role of GID1 in sexual and apomictic reproduction.
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Affiliation(s)
- Luciana Gomes Ferreira
- Department of Biology, University of Brasília-UnB, Campus Darcy Ribeiro S/N-Asa Norte, Brasília, DF, 70910-900, Brazil
- Embrapa Genetic Resources and Biotechnology, Parque Estação Biológica, PqEB Av. W5 Norte, Caixa Postal 02372, Brasília, DF, 70770-917, Brazil
| | - Diva Maria de Alencar Dusi
- Embrapa Genetic Resources and Biotechnology, Parque Estação Biológica, PqEB Av. W5 Norte, Caixa Postal 02372, Brasília, DF, 70770-917, Brazil
| | - André Southernman Teixeira Irsigler
- Embrapa Genetic Resources and Biotechnology, Parque Estação Biológica, PqEB Av. W5 Norte, Caixa Postal 02372, Brasília, DF, 70770-917, Brazil
| | - Ana Cristina Meneses Mendes Gomes
- Embrapa Genetic Resources and Biotechnology, Parque Estação Biológica, PqEB Av. W5 Norte, Caixa Postal 02372, Brasília, DF, 70770-917, Brazil
| | - Marta Adelina Mendes
- Dipartimento di Bioscienze, Università degli Studi di Milano, Via Celoria 26, 20133, Milan, Italy
| | - Lucia Colombo
- Dipartimento di Bioscienze, Università degli Studi di Milano, Via Celoria 26, 20133, Milan, Italy
| | - Vera Tavares de Campos Carneiro
- Department of Biology, University of Brasília-UnB, Campus Darcy Ribeiro S/N-Asa Norte, Brasília, DF, 70910-900, Brazil.
- Embrapa Genetic Resources and Biotechnology, Parque Estação Biológica, PqEB Av. W5 Norte, Caixa Postal 02372, Brasília, DF, 70770-917, Brazil.
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Lacerda ALM, Dusi DMDA, Alves ER, Rodrigues JCM, Gomes ACMM, Carneiro VTDC. Expression analyses of Brachiaria brizantha genes encoding ribosomal proteins BbrizRPS8, BbrizRPS15a, and BbrizRPL41 during development of ovaries and anthers. PROTOPLASMA 2013; 250:505-514. [PMID: 22833119 DOI: 10.1007/s00709-012-0433-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2012] [Accepted: 07/10/2012] [Indexed: 06/01/2023]
Abstract
Brachiaria brizantha is a forage grass of the Poaceae family. Introduced from Africa, it is largely used for beef cattle production in Brazil. Brachiaria reproduces sexually or asexually by apomixis, and development of biotechnological tools for gene transfer is being researched to support the breeding programs. The molecular bases of reproduction have not yet been fully elucidated; it is known that gametophyte formation and main reproductive events occur inside the anthers and ovaries. There is therefore much interest in identifying genes expressed in these organs and their corresponding upstream regulatory sequences. In this work we characterized three cDNA from ovaries of B. brizantha plants (CL 09, CL10, and CL21) which show similarity in databases with genes encoding ribosomal proteins S8, S15a, and L41 and were named BbrizRPS8, BbrizRPS15a, and BbrizRPL41, respectively. These clones show higher expression in ovaries, anthers and roots, mitotically active tissues, when compared to leaves of B. brizantha. Localization of transcripts of BbrizRPS8, BbrizRPS15a, and BbrizRPL41 was investigated in the reproductive organs, ovaries, and anthers, from the beginning of development up to maturity. Their activity was higher in early stages of anther development, while expression was detected in all developmental stages in the ovaries, except for BbrizS15a, which was detected only in synergids of apomictic plants.
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Affiliation(s)
- Ana Luiza Machado Lacerda
- Embrapa Genetic Resources and Biotechnology, Parque Estação Biológica, Brasília, Federal District, Brazil
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Silveira ED, Guimarães LA, de Alencar Dusi DM, da Silva FR, Martins NF, do Carmo Costa MM, Alves-Ferreira M, de Campos Carneiro VT. Expressed sequence-tag analysis of ovaries of Brachiaria brizantha reveals genes associated with the early steps of embryo sac differentiation of apomictic plants. PLANT CELL REPORTS 2012; 31:403-16. [PMID: 22068439 DOI: 10.1007/s00299-011-1175-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2011] [Revised: 10/10/2011] [Accepted: 10/12/2011] [Indexed: 05/23/2023]
Abstract
In apomixis, asexual mode of plant reproduction through seeds, an unreduced megagametophyte is formed due to circumvented or altered meiosis. The embryo develops autonomously from the unreduced egg cell, independently of fertilization. Brachiaria is a genus of tropical forage grasses that reproduces sexually or by apomixis. A limited number of studies have reported the sequencing of apomixis-related genes and a few Brachiaria sequences have been deposited at genebank databases. This work shows sequencing and expression analyses of expressed sequence-tags (ESTs) of Brachiaria genus and points to transcripts from ovaries with preferential expression at megasporogenesis in apomictic plants. From the 11 differentially expressed sequences from immature ovaries of sexual and apomictic Brachiaria brizantha obtained from macroarray analysis, 9 were preferentially detected in ovaries of apomicts, as confirmed by RT-qPCR. A putative involvement in early steps of Panicum-type embryo sac differentiation of four sequences from B. brizantha ovaries: BbrizHelic, BbrizRan, BbrizSec13 and BbrizSti1 is suggested. Two of these, BbrizSti1 and BbrizHelic, with similarity to a gene coding to stress induced protein and a helicase, respectively, are preferentially expressed in the early stages of apomictic ovaries development, especially in the nucellus, in a stage previous to the differentiation of aposporous initials, as verified by in situ hybridization.
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Affiliation(s)
- Erica Duarte Silveira
- Embrapa Genetic Resources and Biotechnology, Parque Estação Biológica, PqEB, Av. W5 Norte (final) Caixa Postal 02372, 70770917, Brasília DF, Brazil
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9
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Seed abortion in the sexual counterpart of Brachiaria brizantha apomicts (Poaceae). ACTA ACUST UNITED AC 2007. [DOI: 10.1007/s00497-007-0048-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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