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Cao Y, Xu J, Wang M, Gao J, Zhao Z, Li K, Yang L, Zhao K, Sun M, Dong J, Chao G, Zhang H, Niu Y, Yan C, Gong X, Wu L, Xiong Z. Unambiguous chromosome identification reveals the factors impacting irregular chromosome behaviors in allotriploid AAC Brassica. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2024; 137:245. [PMID: 39365356 DOI: 10.1007/s00122-024-04734-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2024] [Accepted: 08/31/2024] [Indexed: 10/05/2024]
Abstract
KEY MESSAGE The major irregular chromosome pairing and mis-segregation were detected during meiosis through unambiguous chromosome identification and found that allotriploid Brassica can undergo meiosis successfully and produce mostly viable aneuploid gametes. Triploids have played a crucial role in the evolution of species by forming polyploids and facilitating interploidy gene transfer. It is widely accepted that triploids cannot undergo meiosis normally and predominantly produce nonfunctional aneuploid gametes, which restricts their role in species evolution. In this study, we demonstrated that natural and synthetic allotriploid Brassica (AAC), produced by crossing natural and synthetic Brassica napus (AACC) with Brassica rapa (AA), exhibits basically normal chromosome pairing and segregation during meiosis. Homologous A chromosomes paired faithfully and generally segregated equally. Monosomic C chromosomes were largely retained as univalents and randomly entered daughter cells. The primary irregular meiotic behaviors included associations of homoeologs and 45S rDNA loci at diakinesis, as well as homoeologous chromosome replacement and premature sister chromatid separation at anaphase I. Preexisting homoeologous arrangements altered meiotic behaviors in both chromosome irregular pairing and mis-segregation by increasing the formation of A-genomic univalents and A-C bivalents, as well as premature sister chromatid separation and homologous chromosome nondisjunction. Meiotic behaviors depended significantly on the genetic background and heterozygous homoeologous rearrangement. AAC triploids mainly generated aneuploid gametes, most of which were viable. These results demonstrate that allotriploid Brassica containing an intact karyotype can proceed through meiosis successfully, broadening our current understanding of the inheritance and role in species evolution of allotriploid.
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Affiliation(s)
- Yao Cao
- Key Laboratory of Herbage and Endemic Crop Biology, Ministry of Education, Inner Mongolia University, Hohhot, 010020, Inner Mongolia, China
- College of Life Science, Inner Mongolia University, Hohhot, 010020, Inner Mongolia, China
- College of Life Science, Shanxi Normal University, Taiyuan, 030031, Shanxi, China
| | - Junxiong Xu
- Key Laboratory of Herbage and Endemic Crop Biology, Ministry of Education, Inner Mongolia University, Hohhot, 010020, Inner Mongolia, China
- College of Life Science, Inner Mongolia University, Hohhot, 010020, Inner Mongolia, China
| | - Minhang Wang
- Key Laboratory of Herbage and Endemic Crop Biology, Ministry of Education, Inner Mongolia University, Hohhot, 010020, Inner Mongolia, China
- College of Life Science, Inner Mongolia University, Hohhot, 010020, Inner Mongolia, China
| | - Jing Gao
- Key Laboratory of Herbage and Endemic Crop Biology, Ministry of Education, Inner Mongolia University, Hohhot, 010020, Inner Mongolia, China
- College of Life Science, Inner Mongolia University, Hohhot, 010020, Inner Mongolia, China
| | - Zhen Zhao
- Key Laboratory of Herbage and Endemic Crop Biology, Ministry of Education, Inner Mongolia University, Hohhot, 010020, Inner Mongolia, China
- College of Life Science, Inner Mongolia University, Hohhot, 010020, Inner Mongolia, China
| | - Kexin Li
- Key Laboratory of Herbage and Endemic Crop Biology, Ministry of Education, Inner Mongolia University, Hohhot, 010020, Inner Mongolia, China
- College of Life Science, Inner Mongolia University, Hohhot, 010020, Inner Mongolia, China
| | - Lu Yang
- Key Laboratory of Herbage and Endemic Crop Biology, Ministry of Education, Inner Mongolia University, Hohhot, 010020, Inner Mongolia, China
- College of Life Science, Inner Mongolia University, Hohhot, 010020, Inner Mongolia, China
| | - Kanglu Zhao
- Key Laboratory of Herbage and Endemic Crop Biology, Ministry of Education, Inner Mongolia University, Hohhot, 010020, Inner Mongolia, China
- College of Life Science, Inner Mongolia University, Hohhot, 010020, Inner Mongolia, China
| | - Meiping Sun
- Key Laboratory of Herbage and Endemic Crop Biology, Ministry of Education, Inner Mongolia University, Hohhot, 010020, Inner Mongolia, China
- College of Life Science, Inner Mongolia University, Hohhot, 010020, Inner Mongolia, China
| | - Jing Dong
- Key Laboratory of Herbage and Endemic Crop Biology, Ministry of Education, Inner Mongolia University, Hohhot, 010020, Inner Mongolia, China
- College of Life Science, Inner Mongolia University, Hohhot, 010020, Inner Mongolia, China
| | - Getu Chao
- Key Laboratory of Herbage and Endemic Crop Biology, Ministry of Education, Inner Mongolia University, Hohhot, 010020, Inner Mongolia, China
- College of Life Science, Inner Mongolia University, Hohhot, 010020, Inner Mongolia, China
| | - Hong Zhang
- Key Laboratory of Herbage and Endemic Crop Biology, Ministry of Education, Inner Mongolia University, Hohhot, 010020, Inner Mongolia, China
- College of Life Science, Inner Mongolia University, Hohhot, 010020, Inner Mongolia, China
| | - Yaqingqing Niu
- Key Laboratory of Herbage and Endemic Crop Biology, Ministry of Education, Inner Mongolia University, Hohhot, 010020, Inner Mongolia, China
- College of Life Science, Inner Mongolia University, Hohhot, 010020, Inner Mongolia, China
| | - Chunxia Yan
- Key Laboratory of Herbage and Endemic Crop Biology, Ministry of Education, Inner Mongolia University, Hohhot, 010020, Inner Mongolia, China
- College of Life Science, Inner Mongolia University, Hohhot, 010020, Inner Mongolia, China
| | - Xiufeng Gong
- Key Laboratory of Herbage and Endemic Crop Biology, Ministry of Education, Inner Mongolia University, Hohhot, 010020, Inner Mongolia, China
- College of Life Science, Inner Mongolia University, Hohhot, 010020, Inner Mongolia, China
| | - Lei Wu
- Key Laboratory of Herbage and Endemic Crop Biology, Ministry of Education, Inner Mongolia University, Hohhot, 010020, Inner Mongolia, China.
- College of Life Science, Inner Mongolia University, Hohhot, 010020, Inner Mongolia, China.
| | - Zhiyong Xiong
- Key Laboratory of Herbage and Endemic Crop Biology, Ministry of Education, Inner Mongolia University, Hohhot, 010020, Inner Mongolia, China.
- College of Life Science, Inner Mongolia University, Hohhot, 010020, Inner Mongolia, China.
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Song J, Wang A, Zhu W, Yang L, Xie Z, Han X, Wang B, Tian B, Zhang L, Chen W, Wei F, Shi G. A cotton endoreduplication gene, GaTOP6B, regulates trichome branching development. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2024; 214:108888. [PMID: 38954944 DOI: 10.1016/j.plaphy.2024.108888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Revised: 06/18/2024] [Accepted: 06/26/2024] [Indexed: 07/04/2024]
Abstract
Trichomes are specialized epidermal structures that protect plants from biotic and abiotic stresses by synthesizing, storing, and secreting defensive compounds. This study investigates the role of the Gossypium arboreum DNA topoisomerase VI subunit B gene (GaTOP6B) in trichome development and branching. Sequence alignment revealed a high similarity between GaTOP6B and AtTOP6B, suggesting a conserved function in trichome regulation. Although AtTOP6B acts as a positive regulator of trichome development, functional analyses showed contrasting effects: Virus-induced gene silencing (VIGS) of GaTOP6B in cotton increased trichome density, while its overexpression in Arabidopsis decreased trichome density but enhanced branching. This demonstrates that GaTOP6B negatively regulates trichome number, indicating species-specific roles in trichome initiation and branching between cotton and Arabidopsis. Overexpression of the GaTOP6B promotes jasmonic acid synthesis, which in turn inhibits the G1/S or G2/M transitions, stalling the cell cycle. On the other hand, it suppresses brassinolide synthesis and signaling while promoting cytokinin degradation, further inhibiting mitosis. These hormonal interactions facilitate the transition of cells from the mitotic cycle to the endoreduplication cycle. As the level of endoreduplication increases, trichomes develop an increased number of branches. These findings highlight GaTOP6B's critical role as a regulator of trichome development, providing new genetic targets for improving cotton varieties in terms of enhanced adaptability and resilience.
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Affiliation(s)
- Jiaqi Song
- Henan International Joint Laboratory of Crop Gene Resources and Improvements, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, 450001, Henan, China
| | - Ao Wang
- Henan International Joint Laboratory of Crop Gene Resources and Improvements, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, 450001, Henan, China
| | - Wei Zhu
- Henan International Joint Laboratory of Crop Gene Resources and Improvements, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, 450001, Henan, China
| | - Lanlan Yang
- Henan International Joint Laboratory of Crop Gene Resources and Improvements, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, 450001, Henan, China
| | - Zhengqing Xie
- Henan International Joint Laboratory of Crop Gene Resources and Improvements, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, 450001, Henan, China
| | - Xingzhou Han
- Henan International Joint Laboratory of Crop Gene Resources and Improvements, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, 450001, Henan, China
| | - Boyang Wang
- Henan International Joint Laboratory of Crop Gene Resources and Improvements, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, 450001, Henan, China
| | - Baoming Tian
- Henan International Joint Laboratory of Crop Gene Resources and Improvements, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, 450001, Henan, China
| | - Luyue Zhang
- Henan International Joint Laboratory of Crop Gene Resources and Improvements, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, 450001, Henan, China
| | - Weiwei Chen
- Henan International Joint Laboratory of Crop Gene Resources and Improvements, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, 450001, Henan, China
| | - Fang Wei
- Henan International Joint Laboratory of Crop Gene Resources and Improvements, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, 450001, Henan, China.
| | - Gongyao Shi
- Henan International Joint Laboratory of Crop Gene Resources and Improvements, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, 450001, Henan, China.
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Zhao K, Bai Y, Zhang Q, Zhao Z, Cao Y, Yang L, Wang N, Xu J, Wang B, Wu L, Gong X, Lin T, Wang Y, Wang W, Cai X, Yin Y, Xiong Z. Karyotyping of aneuploid and polyploid plants from low coverage whole-genome resequencing. BMC PLANT BIOLOGY 2023; 23:630. [PMID: 38062348 PMCID: PMC10704825 DOI: 10.1186/s12870-023-04650-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Accepted: 11/30/2023] [Indexed: 12/18/2023]
Abstract
BACKGROUND Karyotype, as a basic characteristic of species, provides valuable information for fundamental theoretical research and germplasm resource innovation. However, traditional karyotyping techniques, including fluorescence in situ hybridization (FISH), are challenging and low in efficiency, especially when karyotyping aneuploid and polyploid plants. The use of low coverage whole-genome resequencing (lcWGR) data for karyotyping was explored, but existing methods are complicated and require control samples. RESULTS In this study, a new protocol for molecular karyotype analysis was provided, which proved to be a simpler, faster, and more accurate method, requiring no control. Notably, our method not only provided the copy number of each chromosome of an individual but also an accurate evaluation of the genomic contribution from its parents. Moreover, we verified the method through FISH and published resequencing data. CONCLUSIONS This method is of great significance for species evolution analysis, chromosome engineering, crop improvement, and breeding.
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Affiliation(s)
- Kanglu Zhao
- Key Laboratory of Herbage and Endemic Crop Biology, Ministry of Education, School of Life Sciences, Inner Mongolia University, Hohhot, 010070, China
| | - Yanbo Bai
- Key Laboratory of Herbage and Endemic Crop Biology, Ministry of Education, School of Life Sciences, Inner Mongolia University, Hohhot, 010070, China
| | - Qingyu Zhang
- Key Laboratory of Herbage and Endemic Crop Biology, Ministry of Education, School of Life Sciences, Inner Mongolia University, Hohhot, 010070, China
| | - Zhen Zhao
- Key Laboratory of Herbage and Endemic Crop Biology, Ministry of Education, School of Life Sciences, Inner Mongolia University, Hohhot, 010070, China
| | - Yao Cao
- Key Laboratory of Herbage and Endemic Crop Biology, Ministry of Education, School of Life Sciences, Inner Mongolia University, Hohhot, 010070, China
| | - Lu Yang
- Key Laboratory of Herbage and Endemic Crop Biology, Ministry of Education, School of Life Sciences, Inner Mongolia University, Hohhot, 010070, China
| | - Ni Wang
- Key Laboratory of Herbage and Endemic Crop Biology, Ministry of Education, School of Life Sciences, Inner Mongolia University, Hohhot, 010070, China
| | - Junxiong Xu
- Key Laboratory of Herbage and Endemic Crop Biology, Ministry of Education, School of Life Sciences, Inner Mongolia University, Hohhot, 010070, China
| | - Bo Wang
- Key Laboratory of Herbage and Endemic Crop Biology, Ministry of Education, School of Life Sciences, Inner Mongolia University, Hohhot, 010070, China
| | - Lei Wu
- Key Laboratory of Herbage and Endemic Crop Biology, Ministry of Education, School of Life Sciences, Inner Mongolia University, Hohhot, 010070, China
| | - Xiufeng Gong
- Key Laboratory of Herbage and Endemic Crop Biology, Ministry of Education, School of Life Sciences, Inner Mongolia University, Hohhot, 010070, China
| | - Tuanrong Lin
- Institute of Ulanqab Agricultural and Forestry Sciences, Inner Mongolia, Ulanqab, 012000, China
| | - Yufeng Wang
- Institute of Ulanqab Agricultural and Forestry Sciences, Inner Mongolia, Ulanqab, 012000, China
| | - Wei Wang
- Institute of Ulanqab Agricultural and Forestry Sciences, Inner Mongolia, Ulanqab, 012000, China
| | - Xingkui Cai
- Key Laboratory of Horticultural Plant Biology, Key Laboratory of Potato Biology and Biotechnology, Ministry of Agriculture and Rural Affairs, College of Horticulture and Forestry Sciences, Ministry of Education, Huazhong Agricultural University, Wuhan, 430070, China
| | - Yuhe Yin
- Institute of Ulanqab Agricultural and Forestry Sciences, Inner Mongolia, Ulanqab, 012000, China
| | - Zhiyong Xiong
- Key Laboratory of Herbage and Endemic Crop Biology, Ministry of Education, School of Life Sciences, Inner Mongolia University, Hohhot, 010070, China.
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Tian Z, Ji C, Xie Z, Shi X, Tian B, Cao G, Wei X, Yang Y, Wei F, Shi G. Integrated cytological and transcriptomic analysis reveals insights into pollen fertility in newly synthetic Brassica allohexaploids. FRONTIERS IN PLANT SCIENCE 2023; 13:1096804. [PMID: 36714744 PMCID: PMC9880477 DOI: 10.3389/fpls.2022.1096804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/12/2022] [Accepted: 12/21/2022] [Indexed: 06/18/2023]
Abstract
Trigenomic Brassica allohexaploids (AABBCC, 2n = 6x = 54) have great potential in oilseed breeding and genetic diversity. However, Brassica allohexaploids do not exist naturally, and the underlying mechanism regulating pollen fertility in artificially synthesized Brassica allohexaploids is still unclear. In this study, synthetic Brassica allohexaploids were produced by crossing allotetraploid B. carinata (BBCC, 2n = 4x = 34) and diploid B. rapa (AA, 2n = 2x = 20), followed by chromosome doubling. The results showed that the pollen fertility was significantly reduced and the pollen structures were mostly distorted, but the nursing anther tapetum developed normally in the synthetic Brassica allohexaploids. Furthermore, the data showed that the meiotic events occurred irregularly with uneven chromosome segregation and microspore development appeared mostly abnormal. Transcription analysis showed that the upregulation of genes related to the negative regulation of flower development and the downregulation of genes related to chromosome segregation might play an essential role in reduction of pollen fertility in the Brassica allohexaploids. In conclusion, this study elucidated the related mechanisms affecting pollen fertility during male gametophytic development at the cytological and transcriptomic levels in the newly synthesized Brassica allohexaploids.
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Affiliation(s)
- Zhaoran Tian
- Henan International Joint Laboratory of Crop Gene Resources and Improvements, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, China
| | - Chengyan Ji
- Henan International Joint Laboratory of Crop Gene Resources and Improvements, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, China
- Institute of Horticulture, Henan Academy of Agricultural Sciences, Graduate T&R Base of Zhengzhou University, Zhengzhou, China
| | - Zhengqing Xie
- Henan International Joint Laboratory of Crop Gene Resources and Improvements, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, China
| | - Xinjie Shi
- Henan International Joint Laboratory of Crop Gene Resources and Improvements, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, China
- Institute of Horticulture, Henan Academy of Agricultural Sciences, Graduate T&R Base of Zhengzhou University, Zhengzhou, China
| | - Baoming Tian
- Henan International Joint Laboratory of Crop Gene Resources and Improvements, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, China
| | - Gangqiang Cao
- Henan International Joint Laboratory of Crop Gene Resources and Improvements, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, China
| | - Xiaochun Wei
- Institute of Horticulture, Henan Academy of Agricultural Sciences, Graduate T&R Base of Zhengzhou University, Zhengzhou, China
| | - Yan Yang
- Henan International Joint Laboratory of Crop Gene Resources and Improvements, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, China
| | - Fang Wei
- Henan International Joint Laboratory of Crop Gene Resources and Improvements, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, China
| | - Gongyao Shi
- Henan International Joint Laboratory of Crop Gene Resources and Improvements, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, China
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Quan C, Chen G, Li S, Jia Z, Yu P, Tu J, Shen J, Yi B, Fu T, Dai C, Ma C. Transcriptome shock in interspecific F1 allotriploid hybrids between Brassica species. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:2336-2353. [PMID: 35139197 DOI: 10.1093/jxb/erac047] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Accepted: 02/03/2022] [Indexed: 06/14/2023]
Abstract
Interspecific hybridization drives the evolution of angiosperms and can be used to introduce novel alleles for important traits or to activate heterosis in crop breeding. Hybridization brings together gene expression networks from two different species, potentially causing global alterations of gene expression in the F1 plants which is called 'transcriptome shock'. Here, we explored such a transcriptome shock in allotriploid Brassica hybrids. We generated interspecific F1 allotriploid hybrids between the allotetraploid species Brassica napus and three accessions of the diploid species Brassica rapa. RNA-seq of the F1 hybrids and the parental plants revealed that 26.34-30.89% of genes were differentially expressed between the parents. We also analyzed expression level dominance and homoeolog expression bias between the parents and the F1 hybrids. The expression-level dominance biases of the Ar, An, and Cn subgenomes was genotype and stage dependent, whereas significant homoeolog expression bias was observed among three subgenomes from different parents. Furthermore, more genes were involved in trans regulation than in cis regulation in allotriploid F1 hybrids. Our findings provide new insights into the transcriptomic responses of cross-species hybrids and hybrids showing heterosis, as well as a new method for promoting the breeding of desirable traits in polyploid Brassica species.
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Affiliation(s)
- Chengtao Quan
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
- Hubei Hongshan Laboratory, Wuhan, 430070, China
| | - Guoting Chen
- College of Informatics, Huazhong Agricultural University, Wuhan 430070, China
| | - Sijia Li
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
| | - Zhibo Jia
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
| | - Pugang Yu
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
| | - Jinxing Tu
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
| | - Jinxiong Shen
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
| | - Bin Yi
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
| | - Tingdong Fu
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
| | - Cheng Dai
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
- Hubei Hongshan Laboratory, Wuhan, 430070, China
| | - Chaozhi Ma
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
- Hubei Hongshan Laboratory, Wuhan, 430070, China
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Yuan J, Shi G, Yang Y, Braynen J, Shi X, Wei X, Hao Z, Zhang X, Yuan Y, Tian B, Xie Z, Wei F. Non-homologous chromosome pairing during meiosis in haploid Brassica rapa. PLANT CELL REPORTS 2021; 40:2421-2434. [PMID: 34542669 DOI: 10.1007/s00299-021-02786-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Accepted: 09/07/2021] [Indexed: 06/13/2023]
Abstract
Cytological observations of chromosome pairing showed that evolutionarily genome duplication might reshape non-homologous pairing during meiosis in haploid B. rapa. A vast number of flowering plants have evolutionarily undergone whole genome duplication (WGD) event. Typically, Brassica rapa is currently considered as an evolutionary mesohexaploid, which has more complicated genomic constitution among flowering plants. In this study, we demonstrated chromosome behaviors in haploid B. rapa to understand how meiosis proceeds in presence of a single homolog. The findings showed that a diploid-like chromosome pairing was generally adapted during meiosis in haploid B. rapa. Non-homologous chromosomes in haploid cells paired at a high-frequency at metaphase I, over 50% of examined meiocytes showed at least three pairs of bivalents then equally segregated at anaphase I during meiosis. The fluorescence immunostaining showed that the cytoskeletal configurations were mostly well-organized during meiosis. Moreover, the expressed genes identified at meiosis in floral development was rather similar between haploid and diploid B. rapa, especially the expression of known hallmark genes pivotal to chromosome synapsis and homologous recombination were mostly in haploid B. rapa. Whole-genome duplication evolutionarily homology of genomic segments might be an important reason for this phenomenon, which would reshape the first division course of meiosis and influence pollen development in plants.
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Affiliation(s)
- Jiachen Yuan
- School of Life Sciences, Zhengzhou University, Zhengzhou, 450001, Henan, China
- Henan International Joint Laboratory of Crop Gene Resources and Improvements, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, 450001, Henan, China
| | - Gongyao Shi
- School of Life Sciences, Zhengzhou University, Zhengzhou, 450001, Henan, China
| | - Yan Yang
- School of Life Sciences, Zhengzhou University, Zhengzhou, 450001, Henan, China
| | - Janeen Braynen
- Henan International Joint Laboratory of Crop Gene Resources and Improvements, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, 450001, Henan, China
| | - Xinjie Shi
- School of Life Sciences, Zhengzhou University, Zhengzhou, 450001, Henan, China
| | - Xiaochun Wei
- Institute of Horticulture, Henan Academy of Agricultural Sciences, Graduate T & R Base of Zhengzhou University, Zhengzhou, 450002, Henan, China
| | - Zhuolin Hao
- School of Life Sciences, Zhengzhou University, Zhengzhou, 450001, Henan, China
| | - Xiaowei Zhang
- Institute of Horticulture, Henan Academy of Agricultural Sciences, Graduate T & R Base of Zhengzhou University, Zhengzhou, 450002, Henan, China
| | - Yuxiang Yuan
- Institute of Horticulture, Henan Academy of Agricultural Sciences, Graduate T & R Base of Zhengzhou University, Zhengzhou, 450002, Henan, China
| | - Baoming Tian
- School of Life Sciences, Zhengzhou University, Zhengzhou, 450001, Henan, China
- Henan International Joint Laboratory of Crop Gene Resources and Improvements, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, 450001, Henan, China
| | - Zhengqing Xie
- Henan International Joint Laboratory of Crop Gene Resources and Improvements, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, 450001, Henan, China.
| | - Fang Wei
- School of Life Sciences, Zhengzhou University, Zhengzhou, 450001, Henan, China.
- Henan International Joint Laboratory of Crop Gene Resources and Improvements, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, 450001, Henan, China.
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7
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Zhang K, Mason AS, Farooq MA, Islam F, Quezada-Martinez D, Hu D, Yang S, Zou J, Zhou W. Challenges and prospects for a potential allohexaploid Brassica crop. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2021; 134:2711-2726. [PMID: 34089067 DOI: 10.1007/s00122-021-03845-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 04/23/2021] [Indexed: 05/28/2023]
Abstract
The production of a new allohexaploid Brassica crop (2n = AABBCC) is increasingly attracting international interest: a new allohexaploid crop could benefit from several major advantages over the existing Brassica diploid and allotetraploid species, combining genetic diversity and traits from all six crop species with additional allelic heterosis from the extra genome. Although early attempts to produce allohexaploids showed mixed results, recent technological and conceptual advances have provided promising leads to follow. However, there are still major challenges which exist before this new crop type can be realized: (1) incorporation of sufficient genetic diversity to form a basis for breeding and improvement of this potential crop species; (2) restoration of regular meiosis, as most allohexaploids are genetically unstable after formation; and (3) improvement of agronomic traits to the level of "elite" breeding material in the diploid and allotetraploid crop species. In this review, we outline these major prospects and challenges and propose possible plans to produce a stable, diverse and agronomically viable allohexaploid Brassica crop.
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Affiliation(s)
- Kangni Zhang
- Institute of Crop Science and Zhejiang Key Laboratory of Crop Germplasm, Zhejiang University, Hangzhou, 310058, China
| | - Annaliese S Mason
- Plant Breeding Department, Justus Liebig University, 35392, Giessen, Germany
- Plant Breeding Department, The University of Bonn, Katzenburgweg 5, 53115, Bonn, Germany
| | - Muhammad A Farooq
- Institute of Crop Science and Zhejiang Key Laboratory of Crop Germplasm, Zhejiang University, Hangzhou, 310058, China
| | - Faisal Islam
- Institute of Crop Science and Zhejiang Key Laboratory of Crop Germplasm, Zhejiang University, Hangzhou, 310058, China
| | - Daniela Quezada-Martinez
- Plant Breeding Department, Justus Liebig University, 35392, Giessen, Germany
- Plant Breeding Department, The University of Bonn, Katzenburgweg 5, 53115, Bonn, Germany
| | - Dandan Hu
- National Key Laboratory of Crop Genetic Improvement, College of Plant Science & Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Su Yang
- College of Life Sciences, China Jiliang University, Hangzhou, 310018, China
| | - Jun Zou
- National Key Laboratory of Crop Genetic Improvement, College of Plant Science & Technology, Huazhong Agricultural University, Wuhan, 430070, China.
| | - Weijun Zhou
- Institute of Crop Science and Zhejiang Key Laboratory of Crop Germplasm, Zhejiang University, Hangzhou, 310058, China.
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