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Li T, Cai S, Cai Z, Fu Y, Liu W, Zhu X, Lai C, Cui L, Pan W, Li Y. TriticeaeSSRdb: a comprehensive database of simple sequence repeats in Triticeae. FRONTIERS IN PLANT SCIENCE 2024; 15:1412953. [PMID: 38841284 PMCID: PMC11150838 DOI: 10.3389/fpls.2024.1412953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/06/2024] [Accepted: 05/08/2024] [Indexed: 06/07/2024]
Abstract
Microsatellites, known as simple sequence repeats (SSRs), are short tandem repeats of 1 to 6 nucleotide motifs found in all genomes, particularly eukaryotes. They are widely used as co-dominant markers in genetic analyses and molecular breeding. Triticeae, a tribe of grasses, includes major cereal crops such as bread wheat, barley, and rye, as well as abundant forage and lawn grasses, playing a crucial role in global food production and agriculture. To enhance genetic work and expedite the improvement of Triticeae crops, we have developed TriticeaeSSRdb, an integrated and user-friendly database. It contains 3,891,705 SSRs from 21 species and offers browsing options based on genomic regions, chromosomes, motif types, and repeat motif sequences. Advanced search functions allow personalized searches based on chromosome location and length of SSR. Users can also explore the genes associated with SSRs, design customized primer pairs for PCR validation, and utilize practical tools for whole-genome browsing, sequence alignment, and in silico SSR prediction from local sequences. We continually update TriticeaeSSRdb with additional species and practical utilities. We anticipate that this database will greatly facilitate trait genetic analyses and enhance molecular breeding strategies for Triticeae crops. Researchers can freely access the database at http://triticeaessrdb.com/.
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Affiliation(s)
- Tingting Li
- College of Bioscience and Engineering, Jiangxi Agricultural University, Nanchang, Jiangxi, China
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, Northwest A&F University, Yangling, Shaanxi, China
| | - Shaoshuai Cai
- College of Bioscience and Engineering, Jiangxi Agricultural University, Nanchang, Jiangxi, China
| | - Zhibo Cai
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, Northwest A&F University, Yangling, Shaanxi, China
| | - Yi Fu
- College of Bioscience and Engineering, Jiangxi Agricultural University, Nanchang, Jiangxi, China
| | - Wenqiang Liu
- College of Bioscience and Engineering, Jiangxi Agricultural University, Nanchang, Jiangxi, China
| | - Xiangdong Zhu
- College of Bioscience and Engineering, Jiangxi Agricultural University, Nanchang, Jiangxi, China
| | - Chongde Lai
- College of Bioscience and Engineering, Jiangxi Agricultural University, Nanchang, Jiangxi, China
- The Public Instrument Platform of Jiangxi Agricultural University, Jiangxi Agricultural University, Nanchang, Jiangxi, China
| | - Licao Cui
- College of Bioscience and Engineering, Jiangxi Agricultural University, Nanchang, Jiangxi, China
| | - Wenqiu Pan
- State Key Laboratory for Crop Stress Resistance and High-Efficiency Production, Northwest A&F University, Yangling, Shaanxi, China
| | - Yihan Li
- College of Bioscience and Engineering, Jiangxi Agricultural University, Nanchang, Jiangxi, China
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Zhong J, Sun Z, Li S, Yang L, Cao Y, Bao J. Immune checkpoint blockade therapy for BRAF mutant metastatic colorectal cancer: the efficacy, new strategies, and potential biomarkers. Discov Oncol 2023; 14:94. [PMID: 37302081 DOI: 10.1007/s12672-023-00718-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Accepted: 06/06/2023] [Indexed: 06/13/2023] Open
Abstract
BRAF mutant metastatic colorectal cancer has long been considered a tumor with a poor prognosis and a poor response to chemotherapy. Despite the efficacy of targeted therapy with multi-targeted blockade of the mitogen-activated protein kinase (MAPK) signaling pathway has brought a glimmer of hope to this group of patients, the need to improve treatment efficacy remains unmet, especially for the microsatellite stability/DNA proficient mismatch repair (MSS/pMMR) subtype. BRAF mutant colorectal cancer patients with high microsatellite instability/DNA deficient mismatch repair (MSI-H/dMMR) have high tumor mutation burden and abundant neoantigen, who are deemed as ones that could receive expected efficacy from immunotherapy. Generally, it is believed that MSS/pMMR colorectal cancer is an immunologically "cold" tumor that is insensitive to immunotherapy. However, targeted therapy combined with immune checkpoint blockade therapy seems to bring light to BRAF mutant colorectal cancer patients. In this review, we provide an overview of clinical efficacy and evolving new strategies concerning immune checkpoint blockade therapy for both MSI-H/dMMR and MSS/pMMR BRAF mutant metastatic colorectal cancer and discuss the potential biomarkers in the tumor immune microenvironment for predicting immunotherapeutic response in BRAF mutant colorectal cancer.
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Affiliation(s)
- Jie Zhong
- Department of Medical Oncology, The Affiliated Cancer Hospital of Nanjing Medical University, Nanjing, 210009, China
| | - Zijian Sun
- Department of Medical Oncology, The Affiliated Cancer Hospital of Nanjing Medical University, Nanjing, 210009, China
| | - Sheng Li
- Department of Medical Oncology, The Affiliated Cancer Hospital of Nanjing Medical University, Nanjing, 210009, China
| | - Liu Yang
- Department of Colorectal Surgery, The Affiliated Cancer Hospital of Nanjing Medical University, Nanjing, 210009, China
| | - Yuepeng Cao
- Department of Colorectal Surgery, The Affiliated Cancer Hospital of Nanjing Medical University, Nanjing, 210009, China
| | - Jun Bao
- Department of Medical Oncology, The Affiliated Cancer Hospital of Nanjing Medical University, Nanjing, 210009, China.
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Characterization of the plastid genome of Cratoxylum species (Hypericaceae) and new insights into phylogenetic relationships. Sci Rep 2022; 12:18810. [PMID: 36335203 PMCID: PMC9637187 DOI: 10.1038/s41598-022-23639-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 11/02/2022] [Indexed: 11/07/2022] Open
Abstract
To expand the genomic information of Hypericaceae, particularly on Cratoxylum, we characterized seven novel complete plastid genomes (plastomes) of five Cratoxylum and two of its allied taxa, including C. arborescens, C. formosum subsp. formosum, C. formosum subsp. pruniflorum, C. maingayi, C. sumatranum, Hypericum hookerianum, and Triadenum breviflorum. For Cratoxylum, the plastomes ranged from 156,962 to 157,792 bp in length. Genomic structure and gene contents were observed in the five plastomes, and were comprised of 128-129 genes, which includes 83-84 protein-coding (CDS), 37 tRNA, and eight rRNA genes. The plastomes of H. hookerianum and T. breviflorum were 138,260 bp and 167,693 bp, respectively. A total of 110 and 127 genes included 72 and 82 CDS, 34 and 37 tRNA, as well as four and eight rRNA genes. The reconstruction of the phylogenetic trees using maximum likelihood (ML) and Bayesian inference (BI) trees based on the concatenated CDS and internal transcribed spacer (ITS) sequences that were analyzed separately have revealed the same topology structure at genus level; Cratoxylum is monophyletic. However, C. formosum subsp. pruniflorum was not clustered together with its origin, raising doubt that it should be treated as a distinct species, C. pruniflorum based on molecular evidence that was supported by morphological descriptions.
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Vannutelli A, Perreault JP, Ouangraoua A. G-quadruplex occurrence and conservation: more than just a question of guanine–cytosine content. NAR Genom Bioinform 2022; 4:lqac010. [PMID: 35261973 PMCID: PMC8896161 DOI: 10.1093/nargab/lqac010] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Revised: 12/06/2021] [Accepted: 02/25/2022] [Indexed: 12/14/2022] Open
Abstract
G-quadruplexes are motifs found in DNA and RNA that can fold into tertiary structures. Until now, they have been studied experimentally mainly in humans and a few other species. Recently, predictions have been made with bacterial and archaeal genomes. Nevertheless, a global comparison of predicted G4s (pG4s) across and within the three living kingdoms has not been addressed. In this study, we aimed to predict G4s in genes and transcripts of all kingdoms of living organisms and investigated the differences in their distributions. The relation of the predictions with GC content was studied. It appears that GC content is not the only parameter impacting G4 predictions and abundance. The distribution of pG4 densities varies depending on the class of transcripts and the group of species. Indeed, we have observed that, in coding transcripts, there are more predicted G4s than expected for eukaryotes but not for archaea and bacteria, while in noncoding transcripts, there are as many or fewer predicted G4s in all species groups. We even noticed that some species with the same GC content presented different pG4 profiles. For instance, Leishmania major and Chlamydomonas reinhardtii both have 60% of GC content, but the former has a pG4 density of 0.07 and the latter 1.16.
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Affiliation(s)
- Anaïs Vannutelli
- Department of Computer Science, Faculté des sciences, Université de Sherbrooke, QC, J1K 2R1, Canada
- Department of Biochemistry and Functional Genomics, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, QC J1E 4K8, Canada
| | - Jean-Pierre Perreault
- Department of Computer Science, Faculté des sciences, Université de Sherbrooke, QC, J1K 2R1, Canada
| | - Aïda Ouangraoua
- Department of Computer Science, Faculté des sciences, Université de Sherbrooke, QC, J1K 2R1, Canada
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Chen J, Li F, Wang M, Li J, Marquez-Lago TT, Leier A, Revote J, Li S, Liu Q, Song J. BigFiRSt: A Software Program Using Big Data Technique for Mining Simple Sequence Repeats From Large-Scale Sequencing Data. Front Big Data 2022; 4:727216. [PMID: 35118375 PMCID: PMC8805145 DOI: 10.3389/fdata.2021.727216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Accepted: 12/13/2021] [Indexed: 11/22/2022] Open
Abstract
Background Simple Sequence Repeats (SSRs) are short tandem repeats of nucleotide sequences. It has been shown that SSRs are associated with human diseases and are of medical relevance. Accordingly, a variety of computational methods have been proposed to mine SSRs from genomes. Conventional methods rely on a high-quality complete genome to identify SSRs. However, the sequenced genome often misses several highly repetitive regions. Moreover, many non-model species have no entire genomes. With the recent advances of next-generation sequencing (NGS) techniques, large-scale sequence reads for any species can be rapidly generated using NGS. In this context, a number of methods have been proposed to identify thousands of SSR loci within large amounts of reads for non-model species. While the most commonly used NGS platforms (e.g., Illumina platform) on the market generally provide short paired-end reads, merging overlapping paired-end reads has become a common way prior to the identification of SSR loci. This has posed a big data analysis challenge for traditional stand-alone tools to merge short read pairs and identify SSRs from large-scale data. Results In this study, we present a new Hadoop-based software program, termed BigFiRSt, to address this problem using cutting-edge big data technology. BigFiRSt consists of two major modules, BigFLASH and BigPERF, implemented based on two state-of-the-art stand-alone tools, FLASH and PERF, respectively. BigFLASH and BigPERF address the problem of merging short read pairs and mining SSRs in the big data manner, respectively. Comprehensive benchmarking experiments show that BigFiRSt can dramatically reduce the execution times of fast read pairs merging and SSRs mining from very large-scale DNA sequence data. Conclusions The excellent performance of BigFiRSt mainly resorts to the Big Data Hadoop technology to merge read pairs and mine SSRs in parallel and distributed computing on clusters. We anticipate BigFiRSt will be a valuable tool in the coming biological Big Data era.
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Affiliation(s)
- Jinxiang Chen
- Department of Software Engineering, College of Information Engineering, Northwest A&F University, Yangling, China
| | - Fuyi Li
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Melbourne, VIC, Australia
- Monash Centre for Data Science, Monash University, Melbourne, VIC, Australia
- Department of Microbiology and Immunity, The Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Melbourne, VIC, Australia
| | - Miao Wang
- Department of Software Engineering, College of Information Engineering, Northwest A&F University, Yangling, China
| | - Junlong Li
- Department of Software Engineering, College of Information Engineering, Northwest A&F University, Yangling, China
| | - Tatiana T. Marquez-Lago
- Department of Genetics, School of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
- Department of Cell, Developmental and Integrative Biology, School of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - André Leier
- Department of Genetics, School of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
- Department of Cell, Developmental and Integrative Biology, School of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Jerico Revote
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Melbourne, VIC, Australia
| | - Shuqin Li
- Department of Software Engineering, College of Information Engineering, Northwest A&F University, Yangling, China
| | - Quanzhong Liu
- Department of Software Engineering, College of Information Engineering, Northwest A&F University, Yangling, China
- Quanzhong Liu
| | - Jiangning Song
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Melbourne, VIC, Australia
- Monash Centre for Data Science, Monash University, Melbourne, VIC, Australia
- *Correspondence: Jiangning Song
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Adhikari TB, Muzhinji N, Halterman D, Louws FJ. Genetic diversity and population structure of Alternaria species from tomato and potato in North Carolina and Wisconsin. Sci Rep 2021; 11:17024. [PMID: 34426589 PMCID: PMC8382843 DOI: 10.1038/s41598-021-95486-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 07/26/2021] [Indexed: 11/19/2022] Open
Abstract
Early blight (EB) caused by Alternaria linariae or Alternaria solani and leaf blight (LB) caused by A. alternata are economically important diseases of tomato and potato. Little is known about the genetic diversity and population structure of these pathogens in the United States. A total of 214 isolates of A. alternata (n = 61), A. linariae (n = 96), and A. solani (n = 57) were collected from tomato and potato in North Carolina and Wisconsin and grouped into populations based on geographic locations and tomato varieties. We exploited 220 single nucleotide polymorphisms derived from DNA sequences of 10 microsatellite loci to analyse the population genetic structure between species and between populations within species and infer the mode of reproduction. High genetic variation and genotypic diversity were observed in all the populations analysed. The null hypothesis of the clonality test based on the index of association \documentclass[12pt]{minimal}
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\begin{document}$$\left( {\overline{r}_{d} } \right)$$\end{document}r¯d was rejected, and equal frequencies of mating types under random mating were detected in some studied populations of Alternaria spp., suggesting that recombination can play an important role in the evolution of these pathogens. Most genetic differences were found between species, and the results showed three distinct genetic clusters corresponding to the three Alternaria spp. We found no evidence for clustering of geographic location populations or tomato variety populations. Analyses of molecular variance revealed high (> 85%) genetic variation within individuals in a population, confirming a lack of population subdivision within species. Alternaria linariae populations harboured more multilocus genotypes (MLGs) than A. alternata and A. solani populations and shared the same MLG between populations within a species, which was suggestive of gene flow and population expansion. Although both A. linariae and A. solani can cause EB on tomatoes and potatoes, these two species are genetically differentiated. Our results provide new insights into the evolution and structure of Alternaria spp. and can lead to new directions in optimizing management strategies to mitigate the impact of these pathogens on tomato and potato production in North Carolina and Wisconsin.
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Affiliation(s)
- Tika B Adhikari
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC, 27695, USA.
| | - Norman Muzhinji
- Department of Applied and Natural Sciences, Namibia University of Science and Technology, Private Bag 13388, Windhoek, Namibia
| | - Dennis Halterman
- United States Department of Agriculture-Agricultural Research Service (USDA-ARS), Vegetable Crops Research Unit, Madison, WI, 53706, USA
| | - Frank J Louws
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC, 27695, USA. .,Department of Horticultural Science, North Carolina State University, Raleigh, NC, 27695, USA.
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Song X, Yang Q, Bai Y, Gong K, Wu T, Yu T, Pei Q, Duan W, Huang Z, Wang Z, Liu Z, Kang X, Zhao W, Ma X. Comprehensive analysis of SSRs and database construction using all complete gene-coding sequences in major horticultural and representative plants. HORTICULTURE RESEARCH 2021; 8:122. [PMID: 34059664 PMCID: PMC8167114 DOI: 10.1038/s41438-021-00562-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 02/10/2021] [Accepted: 03/14/2021] [Indexed: 05/05/2023]
Abstract
Simple sequence repeats (SSRs) are one of the most important genetic markers and widely exist in most species. Here, we identified 249,822 SSRs from 3,951,919 genes in 112 plants. Then, we conducted a comprehensive analysis of these SSRs and constructed a plant SSR database (PSSRD). Interestingly, more SSRs were found in lower plants than in higher plants, showing that lower plants needed to adapt to early extreme environments. Four specific enriched functional terms in the lower plant Chlamydomonas reinhardtii were detected when it was compared with seven other higher plants. In addition, Guanylate_cyc existed in more genes of lower plants than of higher plants. In our PSSRD, we constructed an interactive plotting function in the chart interface, and users can easily view the detailed information of SSRs. All SSR information, including sequences, primers, and annotations, can be downloaded from our database. Moreover, we developed Web SSR Finder and Batch SSR Finder tools, which can be easily used for identifying SSRs. Our database was developed using PHP, HTML, JavaScript, and MySQL, which are freely available at http://www.pssrd.info/ . We conducted an analysis of the Myb gene families and flowering genes as two applications of the PSSRD. Further analysis indicated that whole-genome duplication and whole-genome triplication played a major role in the expansion of the Myb gene families. These SSR markers in our database will greatly facilitate comparative genomics and functional genomics studies in the future.
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Affiliation(s)
- Xiaoming Song
- School of Life Sciences/Library, North China University of Science and Technology, Tangshan, Hebei, 063210, China.
- School of Life Science and Technology and Center for Informational Biology, University of Electronic Science and Technology of China, 610054, Chengdu, China.
- Food Science and Technology Department, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA.
| | - Qihang Yang
- School of Life Sciences/Library, North China University of Science and Technology, Tangshan, Hebei, 063210, China
| | - Yun Bai
- School of Life Sciences/Library, North China University of Science and Technology, Tangshan, Hebei, 063210, China
| | - Ke Gong
- School of Life Sciences/Library, North China University of Science and Technology, Tangshan, Hebei, 063210, China
| | - Tong Wu
- School of Life Sciences/Library, North China University of Science and Technology, Tangshan, Hebei, 063210, China
| | - Tong Yu
- School of Life Sciences/Library, North China University of Science and Technology, Tangshan, Hebei, 063210, China
| | - Qiaoying Pei
- School of Life Sciences/Library, North China University of Science and Technology, Tangshan, Hebei, 063210, China
| | - Weike Duan
- College of Life Sciences and Food Engineering, Huaiyin Institute of Technology, 223003, Huai'an, China
| | - Zhinan Huang
- College of Life Sciences and Food Engineering, Huaiyin Institute of Technology, 223003, Huai'an, China
| | - Zhiyuan Wang
- School of Life Sciences/Library, North China University of Science and Technology, Tangshan, Hebei, 063210, China
| | - Zhuo Liu
- School of Life Sciences/Library, North China University of Science and Technology, Tangshan, Hebei, 063210, China
| | - Xi Kang
- School of Life Sciences/Library, North China University of Science and Technology, Tangshan, Hebei, 063210, China
| | - Wei Zhao
- School of Life Sciences/Library, North China University of Science and Technology, Tangshan, Hebei, 063210, China
| | - Xiao Ma
- School of Life Sciences/Library, North China University of Science and Technology, Tangshan, Hebei, 063210, China.
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Fungal Genomic Resources for Strain Identification and Diversity Analysis of 1900 Fungal Species. J Fungi (Basel) 2021; 7:jof7040288. [PMID: 33921243 PMCID: PMC8070597 DOI: 10.3390/jof7040288] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 03/03/2021] [Accepted: 03/04/2021] [Indexed: 11/17/2022] Open
Abstract
Identification and diversity analysis of fungi is greatly challenging. Though internal transcribed spacer (ITS), region-based DNA fingerprinting works as a “gold standard” for most of the fungal species group, it cannot differentiate between all the groups and cryptic species. Therefore, it is of paramount importance to find an alternative approach for strain differentiation. Availability of whole genome sequence data of nearly 2000 fungal species are a promising solution to such requirement. We present whole genome sequence-based world’s largest microsatellite database, FungSatDB having >19M loci obtained from >1900 fungal species/strains using >4000 assemblies across globe. Genotyping efficacy of FungSatDB has been evaluated by both in-silico and in-vitro PCR. By in silico PCR, 66 strains of 8 countries representing four continents were successfully differentiated. Genotyping efficacy was also evaluated by in vitro PCR in four fungal species. This approach overcomes limitation of ITS in species, strain signature, and diversity analysis. It can accelerate fungal genomic research endeavors in agriculture, industrial, and environmental management.
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Whole genome sequencing of metastatic colorectal cancer reveals prior treatment effects and specific metastasis features. Nat Commun 2021; 12:574. [PMID: 33495476 PMCID: PMC7835235 DOI: 10.1038/s41467-020-20887-6] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 12/21/2020] [Indexed: 02/07/2023] Open
Abstract
In contrast to primary colorectal cancer (CRC) little is known about the genomic landscape of metastasized CRC. Here we present whole genome sequencing data of metastases of 429 CRC patients participating in the pan-cancer CPCT-02 study (NCT01855477). Unsupervised clustering using mutational signature patterns highlights three major patient groups characterized by signatures known from primary CRC, signatures associated with received prior treatments, and metastasis-specific signatures. Compared to primary CRC, we identify additional putative (non-coding) driver genes and increased frequencies in driver gene mutations. In addition, we identify specific genes preferentially affected by microsatellite instability. CRC-specific 1kb-10Mb deletions, enriched for common fragile sites, and LINC00672 mutations are associated with response to treatment in general, whereas FBXW7 mutations predict poor response specifically to EGFR-targeted treatment. In conclusion, the genomic landscape of mCRC shows defined changes compared to primary CRC, is affected by prior treatments and contains features with potential clinical relevance.
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Wang H, Fu Y, Gu P, Zhang Y, Tu W, Chao Z, Wu H, Cao J, Zhou X, Liu B, Michal JJ, Fan C, Tan Y. Genome-Wide Characterization and Comparative Analyses of Simple Sequence Repeats among Four Miniature Pig Breeds. Animals (Basel) 2020; 10:ani10101792. [PMID: 33023098 PMCID: PMC7600727 DOI: 10.3390/ani10101792] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 09/15/2020] [Accepted: 09/28/2020] [Indexed: 12/13/2022] Open
Abstract
Simple Summary Simple sequence repeats (SSRs) are present at high densities in regulatory elements, suggesting that they may affect gene function and phenotypic traits. Therefore, SSRs can be exploited in marker-assisted selection. In addition, they can be widely used as molecular markers to study genetic diversity, population structure, and evolution. While SSRs have been widely studied in many mammalian species, very little research has focused on genome-wide SSRs of miniature pigs, a small but special group of pigs that express the dwarf phenotype. Based on the SSR-enriched library building and sequencing, about 30,000 novel polymorphic SSRs for four miniature pig breeds were mapped to the Duroc pig reference genome. The four miniature pig breeds had different numbers and types of SSRs and distributions of repeat units. There were 2518 polymorphic SSRs in the intron or exon regions that were common to all four breeds and functional analyses revealed 17 genes that were associated with body size and other genes that were associated with growth and development. In conclusion, the SSRs detected in the miniature pigs in this study may provide useful genetic markers for the selection of farm animals and the polymorphic SSRs provide valuable insights into the determination of mature body size, as well as the immunity, growth and development of animals. Abstract Simple sequence repeats (SSRs) are commonly used as molecular markers in research on genetic diversity and discrimination among taxa or breeds because polymorphisms in these regions contribute to gene function and phenotypically important traits. In this study, we investigated genome-wide characteristics, repeat units, and polymorphisms of SSRs using sequencing data from SSR-enriched libraries created from Wuzhishan (WZS), Bama (BM), inbred Luchuan (LC) and Zangxiang (ZX) miniature pig breeds. The numbers and types of SSRs, distributions of repeat units and polymorphic SSRs varied among the four breeds. Compared to the Duroc pig reference genome, 2518 polymorphic SSRs were unique and common to all four breeds and functional annotation revealed that they may affect the coding and regulatory regions of genes. Several examples, such as FGF23, MYF6, IGF1R, and LEPROT, are associated with growth and development in pigs. Three of the polymorphic SSRs were selected to confirm the polymorphism and the corresponding alleles through fluorescence polymerase chain reaction (PCR) and capillary electrophoresis. Together, this study provides useful insights into the discovery, characteristics and distribution of SSRs in four pig breeds. The polymorphic SSRs, especially those common and unique to all four pig breeds, might affect associated genes and play important roles in growth and development.
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Affiliation(s)
- Hongyang Wang
- Institute of Animal Husbandry and Veterinary Science, Shanghai Academy of Agricultural Sciences, Shanghai 201106, China; (H.W.); (Y.Z.); (W.T.); (H.W.); (J.C.)
- Shanghai Engineering Research Center of Breeding Pig, Shanghai 201302, China
| | - Yang Fu
- Research Institute of Edible Fungi, Shanghai Academy of Agricultural Sciences, Shanghai 201403, China;
| | - Peng Gu
- Institute of Comparative Medicine & Laboratory Animal Management Center, Southern Medical University, Guangzhou 510515, China;
| | - Yingying Zhang
- Institute of Animal Husbandry and Veterinary Science, Shanghai Academy of Agricultural Sciences, Shanghai 201106, China; (H.W.); (Y.Z.); (W.T.); (H.W.); (J.C.)
- Shanghai Engineering Research Center of Breeding Pig, Shanghai 201302, China
| | - Weilong Tu
- Institute of Animal Husbandry and Veterinary Science, Shanghai Academy of Agricultural Sciences, Shanghai 201106, China; (H.W.); (Y.Z.); (W.T.); (H.W.); (J.C.)
- Shanghai Engineering Research Center of Breeding Pig, Shanghai 201302, China
| | - Zhe Chao
- Institute of Animal Science and Veterinary Medicine, Hainan Academy of Agricultural Sciences, Haikou 571100, China;
| | - Huali Wu
- Institute of Animal Husbandry and Veterinary Science, Shanghai Academy of Agricultural Sciences, Shanghai 201106, China; (H.W.); (Y.Z.); (W.T.); (H.W.); (J.C.)
- Shanghai Engineering Research Center of Breeding Pig, Shanghai 201302, China
| | - Jianguo Cao
- Institute of Animal Husbandry and Veterinary Science, Shanghai Academy of Agricultural Sciences, Shanghai 201106, China; (H.W.); (Y.Z.); (W.T.); (H.W.); (J.C.)
- Shanghai Engineering Research Center of Breeding Pig, Shanghai 201302, China
| | - Xiang Zhou
- Key Laboratory of Agricultural Animal Genetics, Breeding, and Reproduction of Ministry of Education, Huazhong Agricultural University, Wuhan 430070, China; (X.Z.); (B.L.)
| | - Bang Liu
- Key Laboratory of Agricultural Animal Genetics, Breeding, and Reproduction of Ministry of Education, Huazhong Agricultural University, Wuhan 430070, China; (X.Z.); (B.L.)
| | - Jennifer J. Michal
- Department of Animal Sciences, Washington State University, Pullman, WA 99164, USA;
| | - Chun Fan
- Shanghai Laboratory Animal Research Center, Shanghai 201203, China;
| | - Yongsong Tan
- Institute of Animal Husbandry and Veterinary Science, Shanghai Academy of Agricultural Sciences, Shanghai 201106, China; (H.W.); (Y.Z.); (W.T.); (H.W.); (J.C.)
- Shanghai Engineering Research Center of Breeding Pig, Shanghai 201302, China
- Correspondence: ; Tel.: +86-021-34505325
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11
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Mokhtar MM, Atia MAM. SSRome: an integrated database and pipelines for exploring microsatellites in all organisms. Nucleic Acids Res 2020; 47:D244-D252. [PMID: 30365025 PMCID: PMC6323889 DOI: 10.1093/nar/gky998] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Accepted: 10/14/2018] [Indexed: 11/23/2022] Open
Abstract
Over the past decade, many databases focusing on microsatellite mining on a genomic scale were released online with at least one of the following major deficiencies: (i) lacking the classification of microsatellites as genic or non-genic, (ii) not comparing microsatellite motifs at both genic and non-genic levels in order to identify unique motifs for each class or (iii) missing SSR marker development. In this study, we have developed ‘SSRome’ as a web-based, user-friendly, comprehensive and dynamic database with pipelines for exploring microsatellites in 6533 organisms. In the SSRome database, 158 million microsatellite motifs are identified across all taxa, in addition to all the mitochondrial and chloroplast genomes and expressed sequence tags available from NCBI. Moreover, 45.1 million microsatellite markers were developed and classified as genic or non-genic. All the stored motif and marker datasets can be downloaded freely. In addition, SSRome provides three user-friendly tools to identify, classify and compare motifs on either a genome- or transcriptome-wide scale. With the implementation of PHP, HTML and JavaScript, users can upload their data for analysis via a user-friendly GUI. SSRome represents a powerful database and mega-tool that will assist researchers in developing and dissecting microsatellite markers on a high-throughput scale.
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Affiliation(s)
- Morad M Mokhtar
- Molecular Genetics and Genome Mapping Laboratory, Genome Mapping Department, Agricultural Genetic Engineering Research Institute (AGERI), ARC, Giza, 12619, Egypt
| | - Mohamed A M Atia
- Molecular Genetics and Genome Mapping Laboratory, Genome Mapping Department, Agricultural Genetic Engineering Research Institute (AGERI), ARC, Giza, 12619, Egypt
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Du L, Liu Q, Zhao K, Tang J, Zhang X, Yue B, Fan Z. PSMD: An extensive database for pan-species microsatellite investigation and marker development. Mol Ecol Resour 2019; 20:283-291. [PMID: 31599098 DOI: 10.1111/1755-0998.13098] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 09/18/2019] [Accepted: 09/24/2019] [Indexed: 12/21/2022]
Abstract
Microsatellites are widely distributed throughout nearly all genomes which have been extensively exploited as powerful genetic markers for diverse applications due to their high polymorphisms. Their length variations are involved in gene regulation and implicated in numerous genetic diseases even in cancers. Although much effort has been devoted in microsatellite database construction, the existing microsatellite databases still had some drawbacks, such as limited number of species, unfriendly export format, missing marker development, lack of compound microsatellites and absence of gene annotation, which seriously restricted researchers to perform downstream analysis. In order to overcome the above limitations, we developed PSMD (Pan-Species Microsatellite Database, http://big.cdu.edu.cn/psmd/) as a web-based database to facilitate researchers to easily identify microsatellites, exploit reliable molecular markers and compare microsatellite distribution pattern on genome-wide scale. In current release, PSMD comprises 678,106,741 perfect microsatellites and 43,848,943 compound microsatellites from 18,408 organisms, which covered almost all species with available genomic data. In addition to interactive browse interface, PSMD also offers a flexible filter function for users to quickly gain desired microsatellites from large data sets. PSMD allows users to export GFF3 formatted file and CSV formatted statistical file for downstream analysis. We also implemented an online tool for analysing occurrence of microsatellites with user-defined parameters. Furthermore, Primer3 was embedded to help users to design high-quality primers with customizable settings. To our knowledge, PSMD is the most extensive resource which is likely to be adopted by scientists engaged in biological, medical, environmental and agricultural research.
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Affiliation(s)
- Lianming Du
- Institute for Advanced Study, Chengdu University, Chengdu, China
| | - Qin Liu
- Key Laboratory of Bio-resources and Eco-environment, Ministry of Education, College of Life Science, Sichuan University, Chengdu, China.,College of Life Sciences and Food Engineering, Yibin University, Yibin, China
| | - Kelei Zhao
- Institute for Advanced Study, Chengdu University, Chengdu, China
| | - Jie Tang
- School of Pharmacy and Bioengineering, Chengdu University, Chengdu, China
| | - Xiuyue Zhang
- Key Laboratory of Bio-resources and Eco-environment, Ministry of Education, College of Life Science, Sichuan University, Chengdu, China
| | - Bisong Yue
- Key Laboratory of Bio-resources and Eco-environment, Ministry of Education, College of Life Science, Sichuan University, Chengdu, China
| | - Zhenxin Fan
- Key Laboratory of Bio-resources and Eco-environment, Ministry of Education, College of Life Science, Sichuan University, Chengdu, China
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Subirana JA, Messeguer X. Satellites in the prokaryote world. BMC Evol Biol 2019; 19:181. [PMID: 31533616 PMCID: PMC6749651 DOI: 10.1186/s12862-019-1504-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Accepted: 08/28/2019] [Indexed: 11/10/2022] Open
Abstract
Background Satellites or tandem repeats are very abundant in many eukaryotic genomes. Occasionally they have been reported to be present in some prokaryotes, but to our knowledge there is no general comparative study on their occurrence. For this reason we present here an overview of the distribution and properties of satellites in a set of representative species. Our results provide novel insights into the evolutionary relationship between eukaryotes, Archaea and Bacteria. Results We have searched all possible satellites present in the NCBI reference group of genomes in Archaea (142 species) and in Bacteria (119 species), detecting 2735 satellites in Archaea and 1067 in Bacteria. We have found that the distribution of satellites is very variable in different organisms. The archaeal Methanosarcina class stands out for the large amount of satellites in their genomes. Satellites from a few species have similar characteristics to those in eukaryotes, but most species have very few satellites: only 21 species in Archaea and 18 in Bacteria have more than 4 satellites/Mb. The distribution of satellites in these species is reminiscent of what is found in eukaryotes, but we find two significant differences: most satellites have a short length and many of them correspond to segments of genes coding for amino acid repeats. Transposition of non-coding satellites throughout the genome occurs rarely: only in the bacteria Leptospira interrogans and the archaea Methanocella conradii we have detected satellite families of transposed satellites with long repeats. Conclusions Our results demonstrate that the presence of satellites in the genome is not an exclusive feature of eukaryotes. We have described a few prokaryotes which do contain satellites. We present a discussion on their eventual evolutionary significance. Electronic supplementary material The online version of this article (10.1186/s12862-019-1504-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Juan A Subirana
- Department of Computer Science, Universitat Politècnica de Catalunya, Jordi Girona 1-3, 08034, Barcelona, Spain.
| | - Xavier Messeguer
- Department of Computer Science, Universitat Politècnica de Catalunya, Jordi Girona 1-3, 08034, Barcelona, Spain
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Liu W, Xu Y, Li Z, Fan J, Yang Y. Genome-wide mining of microsatellites in king cobra (Ophiophagus hannah) and cross-species development of tetranucleotide SSR markers in Chinese cobra (Naja atra). Mol Biol Rep 2019; 46:6087-6098. [PMID: 31502192 DOI: 10.1007/s11033-019-05044-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Accepted: 08/22/2019] [Indexed: 12/13/2022]
Abstract
The complete genome sequence provides the opportunity for genome-wide and coding region analysis of SSRs in the king cobra and for cross-species identification of microsatellite markers in the Chinese cobra. In the Ophiophagus hannah genome, tetranucleotide repeats (38.03%) were the most abundant category, followed by dinucleotides (23.03%), pentanucleotides (13.07%), mononucleotides (11.78%), trinucleotides (11.49%) and hexanucleotides (2.6%). Twenty predominant motifs in the O. hannah genome were (A)n (C)n, (AC)n, (AG)n, (AT)n, (AGG)n, (AAT)n, (AAG)n, (AAC)n, (ATG)n, (ATAG)n, (AAGG)n, (ATCT)n, (CCTT)n, (ATTT)n, (AAAT)n, (AATAG)n, (ATTCT)n, (ATATGT)n, (AGATAT)n. In total, 4344 SSRs were found in coding sequences (CDSs). Tetranucleotides (52.79%) were the most abundant microsatellite type in CDS, followed by trinucleotides (28.50%), dinucleotides (11.02%), pentanucleotides (4.42%), mononucleotides (1.77%), and hexanucleotides (1.50%). A total of 984 CDSs containing microsatellites were assigned 11152 Gene Ontology (GO) functional terms. Gene Ontology (GO) analysis demonstrated that cellular process, cell and binding were the most frequent GO terms in biological process, cellular component and molecular function, respectively. Thirty-two novel highly polymorphic (PIC > 0.5) SSR markers for Naja atra were developed from cross-species amplification based on the tetranucleotide microsatellite sequences in the king cobra genome. The number of alleles (NA) per locus had between 3 and 11 alleles with an average of 6.5, the polymorphism information content (PIC) value ranged from 0.521 to 0.858 (average = 0.707), the observed heterozygosity (Ho) of 32 microsatellite loci ranged from 0.292 to 0.875 (mean = 0.678), the expected heterozygosity (HE) ranged from 0.561 to 0.889 (average = 0.761), and 3 microsatellite loci exhibited statistically significant departure from Hardy-Weinberg equilibrium (HWE) after Bonferroni correction (p < 0.003).
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Affiliation(s)
- Wencong Liu
- Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, 610065, China
- College of Materials and Chemistry & Chemical Engineering, Chengdu University of Technology, Chengdu, 610059, China
| | - Yongtao Xu
- College of Forestry, Jiangxi Agricultural University, Nanchang, 330045, China
| | - Zekun Li
- College of Materials and Chemistry & Chemical Engineering, Chengdu University of Technology, Chengdu, 610059, China
| | - Jun Fan
- College of Materials and Chemistry & Chemical Engineering, Chengdu University of Technology, Chengdu, 610059, China
| | - Yi Yang
- Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, 610065, China.
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Srivastava S, Avvaru AK, Sowpati DT, Mishra RK. Patterns of microsatellite distribution across eukaryotic genomes. BMC Genomics 2019; 20:153. [PMID: 30795733 PMCID: PMC6387519 DOI: 10.1186/s12864-019-5516-5] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Accepted: 02/07/2019] [Indexed: 11/28/2022] Open
Abstract
Background Microsatellites, or Simple Sequence Repeats (SSRs), are short tandem repeats of 1–6 nt motifs present in all genomes. Emerging evidence points to their role in cellular processes and gene regulation. Despite the huge resource of genomic information currently available, SSRs have been studied in a limited context and compared across relatively few species. Results We have identified ~ 685 million eukaryotic microsatellites and analyzed their genomic trends across 15 taxonomic subgroups from protists to mammals. The distribution of SSRs reveals taxon-specific variations in their exonic, intronic and intergenic densities. Our analysis reveals the differences among non-related species and novel patterns uniquely demarcating closely related species. We document several repeats common across subgroups as well as rare SSRs that are excluded almost throughout evolution. We further identify species-specific signatures in pathogens like Leishmania as well as in cereal crops, Drosophila, birds and primates. We also find that distinct SSRs preferentially exist as long repeating units in different subgroups; most unicellular organisms show no length preference for any SSR class, while many SSR motifs accumulate as long repeats in complex organisms, especially in mammals. Conclusions We present a comprehensive analysis of SSRs across taxa at an unprecedented scale. Our analysis indicates that the SSR composition of organisms with heterogeneous cell types is highly constrained, while simpler organisms such as protists, green algae and fungi show greater diversity in motif abundance, density and GC content. The microsatellite dataset generated in this work provides a large number of candidates for functional analysis and for studying their roles across the evolutionary landscape. Electronic supplementary material The online version of this article (10.1186/s12864-019-5516-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Surabhi Srivastava
- CSIR - Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad, 500007, India
| | - Akshay Kumar Avvaru
- CSIR - Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad, 500007, India
| | - Divya Tej Sowpati
- CSIR - Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad, 500007, India.
| | - Rakesh K Mishra
- CSIR - Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad, 500007, India.
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Orlov M, Garanina I, Fisunov GY, Sorokin A. Comparative Analysis of Mycoplasma gallisepticum vlhA Promoters. Front Genet 2018; 9:569. [PMID: 30519256 PMCID: PMC6258824 DOI: 10.3389/fgene.2018.00569] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Accepted: 11/06/2018] [Indexed: 12/15/2022] Open
Abstract
Mycoplasma gallisepticum is an intracellular parasite affecting respiratory tract of poultry that belongs to class Mollicutes. M. gallisepticum features numerous variable lipoprotein hemagglutinin genes (vlhA) that play a role in immune escape. The vlhA promoters have a set of distinct properties in comparison to promoters of the other genes. The vlhA promoters carry a variable GAA repeats region at approximately 40 nts upstream of transcription start site. The promoters have been considered active only in the presence of exactly 12 GAA repeats. The mechanisms of vlhA expression regulation and GAA number variation are not described. Here we tried to understand these mechanisms using different computational methods. We conducted a comparative analysis among several M. gallisepticum strains. Nucleotide sequences analysis showed the presence of highly conserved regions flanking repeated trinucleotides that are not linked to GAA number variation. VlhA genes with 12 GAA repeats and their orthologs in 12 M. gallisepticum strains are more conserved than other vlhA genes and have narrower GAA number distribution. We conducted comparative analysis of physicochemical profiles of M. gallisepticum vlhA and sigma-70 promoters. Stress-induced duplex destabilization (SIDD) profiles showed that sigma-70 group is characterized by the common to prokaryotic promoters sharp maxima while vlhA promoters are hardly destabilized with the region between GAA repeats and transcription start site having zero opening probability. Electrostatic potential profiles of vlhA promoters indicate the presence of the distinct patterns that appear to govern initial stages of specific DNA-protein recognition. Open state dynamics profiles of vlhA demonstrate the pattern that might facilitate transcription bubble formation. Obtained data could be the basis for experimental identification of mechanisms of phase variation in M. gallisepticum.
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Affiliation(s)
- Mikhail Orlov
- Institute of Cell Biophysics, Russian Academy of Sciences, Pushchino, Russia
| | - Irina Garanina
- Federal Research and Clinical Center of Physical-Chemical Medicine, Federal Medical-Biological Agency, Moscow, Russia
| | - Gleb Y Fisunov
- Federal Research and Clinical Center of Physical-Chemical Medicine, Federal Medical-Biological Agency, Moscow, Russia
| | - Anatoly Sorokin
- Institute of Cell Biophysics, Russian Academy of Sciences, Pushchino, Russia
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Symonová R, Howell WM. Vertebrate Genome Evolution in the Light of Fish Cytogenomics and rDNAomics. Genes (Basel) 2018; 9:genes9020096. [PMID: 29443947 PMCID: PMC5852592 DOI: 10.3390/genes9020096] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 01/25/2018] [Accepted: 01/29/2018] [Indexed: 12/19/2022] Open
Abstract
To understand the cytogenomic evolution of vertebrates, we must first unravel the complex genomes of fishes, which were the first vertebrates to evolve and were ancestors to all other vertebrates. We must not forget the immense time span during which the fish genomes had to evolve. Fish cytogenomics is endowed with unique features which offer irreplaceable insights into the evolution of the vertebrate genome. Due to the general DNA base compositional homogeneity of fish genomes, fish cytogenomics is largely based on mapping DNA repeats that still represent serious obstacles in genome sequencing and assembling, even in model species. Localization of repeats on chromosomes of hundreds of fish species and populations originating from diversified environments have revealed the biological importance of this genomic fraction. Ribosomal genes (rDNA) belong to the most informative repeats and in fish, they are subject to a more relaxed regulation than in higher vertebrates. This can result in formation of a literal 'rDNAome' consisting of more than 20,000 copies with their high proportion employed in extra-coding functions. Because rDNA has high rates of transcription and recombination, it contributes to genome diversification and can form reproductive barrier. Our overall knowledge of fish cytogenomics grows rapidly by a continuously increasing number of fish genomes sequenced and by use of novel sequencing methods improving genome assembly. The recently revealed exceptional compositional heterogeneity in an ancient fish lineage (gars) sheds new light on the compositional genome evolution in vertebrates generally. We highlight the power of synergy of cytogenetics and genomics in fish cytogenomics, its potential to understand the complexity of genome evolution in vertebrates, which is also linked to clinical applications and the chromosomal backgrounds of speciation. We also summarize the current knowledge on fish cytogenomics and outline its main future avenues.
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Affiliation(s)
- Radka Symonová
- Faculty of Science, Department of Biology, University of Hradec Králové, 500 03 Hradec Králové, Czech Republic.
| | - W Mike Howell
- Department of Biological and Environmental Sciences, Samford University, Birmingham, AL 35229, USA.
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