Patterns of Chromosomal Variation, Homoeologous Exchange, and Their Relationship with Genomic Features in Early Generations of a Synthetic Rice Segmental Allotetraploid

Polyploidization is a driving force in plant evolution. Chromosomal variation often occurs at early generations following polyploid formation due to meiotic pairing irregularity that may compromise segregation fidelity and cause homoeologous exchange (HE). The trends of chromosomal variation and esp...

Full description

Bibliographic Details
Main Authors: Guo Li, Ying Wu, Yan Bai, Na Zhao, Yuhui Jiang, Ning Li, Xiuyun Lin, Bao Liu, Chunming Xu
Format: Article
Language:English
Published: MDPI AG 2023-03-01
Series:International Journal of Molecular Sciences
Subjects:
Online Access:https://www.mdpi.com/1422-0067/24/7/6065
_version_ 1797607905981104128
author Guo Li
Ying Wu
Yan Bai
Na Zhao
Yuhui Jiang
Ning Li
Xiuyun Lin
Bao Liu
Chunming Xu
author_facet Guo Li
Ying Wu
Yan Bai
Na Zhao
Yuhui Jiang
Ning Li
Xiuyun Lin
Bao Liu
Chunming Xu
author_sort Guo Li
collection DOAJ
description Polyploidization is a driving force in plant evolution. Chromosomal variation often occurs at early generations following polyploid formation due to meiotic pairing irregularity that may compromise segregation fidelity and cause homoeologous exchange (HE). The trends of chromosomal variation and especially factors affecting HE remain to be fully deciphered. Here, by whole-genome resequencing, we performed nuanced analyses of patterns of chromosomal number variation and explored genomic features that affect HE in two early generations of a synthetic rice segmental allotetraploid. We found a wide occurrence of whole-chromosome aneuploidy and, to a lesser extent, also large segment gains/losses in both generations (S2 and S4) of the tetraploids. However, while the number of chromosome gains was similar between S2 and S4, that of losses in S4 was lower than in S2. HEs were abundant across all chromosomes in both generations and showed variable correlations with different genomic features at chromosomal and/or local scales. Contents of genes and transposable elements (TEs) were positively and negatively correlated with HE frequencies, respectively. By dissecting TEs into different classes, retrotransposons were found to be negatively correlated with HE frequency to a stronger extent than DNA transposons, whereas miniature terminal inverted elements (MITEs) showed a strong positive correlation. Local HE frequencies in the tetraploids and homologous recombination (HR) rates in diploids within 1 Mb sliding windows were significantly correlated with each other and showed similar overall distribution profiles. Nonetheless, non-concordant trends between HE and HR rates were found at distal regions in some chromosomes. At local scale, both shared and polymorphic retrotransposons between parents were negatively correlated with HE frequency; in contrast, both shared and polymorphic MITEs showed positive correlations with HE frequency. Our results shed new light on the patterns of chromosomal number variation and reveal genomic features influencing HE frequency in early generations following plant polyploidization.
first_indexed 2024-03-11T05:37:07Z
format Article
id doaj.art-b388ba0599ff4d5b910cb2bf426d4122
institution Directory Open Access Journal
issn 1661-6596
1422-0067
language English
last_indexed 2024-03-11T05:37:07Z
publishDate 2023-03-01
publisher MDPI AG
record_format Article
series International Journal of Molecular Sciences
spelling doaj.art-b388ba0599ff4d5b910cb2bf426d41222023-11-17T16:45:54ZengMDPI AGInternational Journal of Molecular Sciences1661-65961422-00672023-03-01247606510.3390/ijms24076065Patterns of Chromosomal Variation, Homoeologous Exchange, and Their Relationship with Genomic Features in Early Generations of a Synthetic Rice Segmental AllotetraploidGuo Li0Ying Wu1Yan Bai2Na Zhao3Yuhui Jiang4Ning Li5Xiuyun Lin6Bao Liu7Chunming Xu8Key Laboratory of Molecular Epigenetics of Ministry of Education (MOE), Northeast Normal University, Changchun 130024, ChinaKey Laboratory of Molecular Epigenetics of Ministry of Education (MOE), Northeast Normal University, Changchun 130024, ChinaKey Laboratory of Molecular Epigenetics of Ministry of Education (MOE), Northeast Normal University, Changchun 130024, ChinaDepartment of Agronomy, Jilin Agricultural University, Changchun 130118, ChinaKey Laboratory of Molecular Epigenetics of Ministry of Education (MOE), Northeast Normal University, Changchun 130024, ChinaKey Laboratory of Molecular Epigenetics of Ministry of Education (MOE), Northeast Normal University, Changchun 130024, ChinaJilin Academy of Agriculture, Changchun 130033, ChinaKey Laboratory of Molecular Epigenetics of Ministry of Education (MOE), Northeast Normal University, Changchun 130024, ChinaKey Laboratory of Molecular Epigenetics of Ministry of Education (MOE), Northeast Normal University, Changchun 130024, ChinaPolyploidization is a driving force in plant evolution. Chromosomal variation often occurs at early generations following polyploid formation due to meiotic pairing irregularity that may compromise segregation fidelity and cause homoeologous exchange (HE). The trends of chromosomal variation and especially factors affecting HE remain to be fully deciphered. Here, by whole-genome resequencing, we performed nuanced analyses of patterns of chromosomal number variation and explored genomic features that affect HE in two early generations of a synthetic rice segmental allotetraploid. We found a wide occurrence of whole-chromosome aneuploidy and, to a lesser extent, also large segment gains/losses in both generations (S2 and S4) of the tetraploids. However, while the number of chromosome gains was similar between S2 and S4, that of losses in S4 was lower than in S2. HEs were abundant across all chromosomes in both generations and showed variable correlations with different genomic features at chromosomal and/or local scales. Contents of genes and transposable elements (TEs) were positively and negatively correlated with HE frequencies, respectively. By dissecting TEs into different classes, retrotransposons were found to be negatively correlated with HE frequency to a stronger extent than DNA transposons, whereas miniature terminal inverted elements (MITEs) showed a strong positive correlation. Local HE frequencies in the tetraploids and homologous recombination (HR) rates in diploids within 1 Mb sliding windows were significantly correlated with each other and showed similar overall distribution profiles. Nonetheless, non-concordant trends between HE and HR rates were found at distal regions in some chromosomes. At local scale, both shared and polymorphic retrotransposons between parents were negatively correlated with HE frequency; in contrast, both shared and polymorphic MITEs showed positive correlations with HE frequency. Our results shed new light on the patterns of chromosomal number variation and reveal genomic features influencing HE frequency in early generations following plant polyploidization.https://www.mdpi.com/1422-0067/24/7/6065polyploidizationchromosomal variationhomoeologous exchangegenomic featuretransposable elementsrice
spellingShingle Guo Li
Ying Wu
Yan Bai
Na Zhao
Yuhui Jiang
Ning Li
Xiuyun Lin
Bao Liu
Chunming Xu
Patterns of Chromosomal Variation, Homoeologous Exchange, and Their Relationship with Genomic Features in Early Generations of a Synthetic Rice Segmental Allotetraploid
International Journal of Molecular Sciences
polyploidization
chromosomal variation
homoeologous exchange
genomic feature
transposable elements
rice
title Patterns of Chromosomal Variation, Homoeologous Exchange, and Their Relationship with Genomic Features in Early Generations of a Synthetic Rice Segmental Allotetraploid
title_full Patterns of Chromosomal Variation, Homoeologous Exchange, and Their Relationship with Genomic Features in Early Generations of a Synthetic Rice Segmental Allotetraploid
title_fullStr Patterns of Chromosomal Variation, Homoeologous Exchange, and Their Relationship with Genomic Features in Early Generations of a Synthetic Rice Segmental Allotetraploid
title_full_unstemmed Patterns of Chromosomal Variation, Homoeologous Exchange, and Their Relationship with Genomic Features in Early Generations of a Synthetic Rice Segmental Allotetraploid
title_short Patterns of Chromosomal Variation, Homoeologous Exchange, and Their Relationship with Genomic Features in Early Generations of a Synthetic Rice Segmental Allotetraploid
title_sort patterns of chromosomal variation homoeologous exchange and their relationship with genomic features in early generations of a synthetic rice segmental allotetraploid
topic polyploidization
chromosomal variation
homoeologous exchange
genomic feature
transposable elements
rice
url https://www.mdpi.com/1422-0067/24/7/6065
work_keys_str_mv AT guoli patternsofchromosomalvariationhomoeologousexchangeandtheirrelationshipwithgenomicfeaturesinearlygenerationsofasyntheticricesegmentalallotetraploid
AT yingwu patternsofchromosomalvariationhomoeologousexchangeandtheirrelationshipwithgenomicfeaturesinearlygenerationsofasyntheticricesegmentalallotetraploid
AT yanbai patternsofchromosomalvariationhomoeologousexchangeandtheirrelationshipwithgenomicfeaturesinearlygenerationsofasyntheticricesegmentalallotetraploid
AT nazhao patternsofchromosomalvariationhomoeologousexchangeandtheirrelationshipwithgenomicfeaturesinearlygenerationsofasyntheticricesegmentalallotetraploid
AT yuhuijiang patternsofchromosomalvariationhomoeologousexchangeandtheirrelationshipwithgenomicfeaturesinearlygenerationsofasyntheticricesegmentalallotetraploid
AT ningli patternsofchromosomalvariationhomoeologousexchangeandtheirrelationshipwithgenomicfeaturesinearlygenerationsofasyntheticricesegmentalallotetraploid
AT xiuyunlin patternsofchromosomalvariationhomoeologousexchangeandtheirrelationshipwithgenomicfeaturesinearlygenerationsofasyntheticricesegmentalallotetraploid
AT baoliu patternsofchromosomalvariationhomoeologousexchangeandtheirrelationshipwithgenomicfeaturesinearlygenerationsofasyntheticricesegmentalallotetraploid
AT chunmingxu patternsofchromosomalvariationhomoeologousexchangeandtheirrelationshipwithgenomicfeaturesinearlygenerationsofasyntheticricesegmentalallotetraploid