The T2/RNase gene family is widespread in eukaryotes,and particular members of this family play critical roles in the gametophytic self-incompatibility(GSI) system in plants.Wild diploid strawberry(Fragaria)species ha...The T2/RNase gene family is widespread in eukaryotes,and particular members of this family play critical roles in the gametophytic self-incompatibility(GSI) system in plants.Wild diploid strawberry(Fragaria)species have diversified their sexual systems via self-incompatible and self-compatible traits,yet how these traits evolved in Fragaria remains elusive.By integrating the published and de novo assembled genomes and the newly generated RNA-seq data,members of the RNase T2 gene family were systematically identified in six Fragaria species,including three self-incompatible species(Fragaria nipponica,Fragaria nubicola,and Fragaria viridis) and three self-compatible species(Fragaria nilgerrensis,Fragaria vesca,and Fragaria iinumae).In total,115 RNase T2 genes were identified in the six Fragaria genomes and can be classified into three classes(Ⅰ-Ⅲ) according to phylogenetic analysis.The identified RNase T2 genes could be divided into 22 homologous gene sets according to amino acid sequence similarity and phylogenetic and syntenic relationships.We found that extensive gene loss and pseudogenization coupled with small-scale duplications mainly accounted for variations in the RNase T2 gene numbers in Fragaria.Multiple copies of homologous genes were mainly generated from tandem and segmental duplication events.Furthermore,we newly identified five S-RNase genes in three self-incompatible Fragaria genomes,including two in F.nipponica,two in F.viridis,and one in F.nubicola,which fit for typical features of a pistil determinant,including highly pistil-specific expression,highly polymorphic proteins and alkaline isoelectric point(pI),while no S-RNase genes were found in all three selfcompatible Fragaria species.Surprisingly,these T2/S-RNase genes contain at least one large intron(>10 kb).This study revealed that the rapid evolution of T2/S-RNase genes within the Fragaria genus could be associated with its sexual mode,and repeated evolution of the self-compatible traits in Fragaria was convergent via losses of S-RNase.展开更多
A new selfincompatibility gene was isolated and identified from Pyrus bretschneideri cultivars of Yingzhiqing and Daaoao via PCR amplification, DNA sequence analysis and cross pollination tests. DNA sequence analysis ...A new selfincompatibility gene was isolated and identified from Pyrus bretschneideri cultivars of Yingzhiqing and Daaoao via PCR amplification, DNA sequence analysis and cross pollination tests. DNA sequence analysis revealed that the isolated fragment displayed a high homology with S 1 ～S 11 allele, and the identity to S 1 ～S 11 allele at the deduced amino level ranged from 56% to 72%; the high degree of variances in the hypervariable （HV） region resulted from the presence of substitution, deletion and insertion of 9 to 15 amino acids. The new Sallele was named S 12 RNase and its accession number was AY250987 in GeneBank. The sizes of HV region, intron, signal peptide, C1 region, C2 region were 39 AA, 341 bp, 27 AA, 11 AA and 10 AA, respectively. The cross pollination tests were carried out using Pyrus pyrifolia cultivars that contained S 1 ～S9RNase genes as female parents, and the cultivars of Daaoao and Yingzhiqing as male parents, respectively. The results showed that all of {%P.pyrifolia%} cultivars were compatible with Daaoao and Yingzhiqing, whereas the cross pollination between Daaoao and Yingzhiqing were incompatible, further confirming that the DNA fragment isolated was a new Sgene.展开更多
Frozen young leaves of apricot(Armeniaca vulgaris) ‘Katy’ and ‘Xinshiji’ were used for isolation of total DNA. Total RNA was isolated from their styles at the balloon stage. DNA and cDNA were amplified through PCR...Frozen young leaves of apricot(Armeniaca vulgaris) ‘Katy’ and ‘Xinshiji’ were used for isolation of total DNA. Total RNA was isolated from their styles at the balloon stage. DNA and cDNA were amplified through PCR using AS1 Ⅱ and ArmyC5R as primers designed according to the conserved (C1,C5) sequences of Rosaceae S-RNases. Three S-RNase genes,P.a S8 from ‘Katy’ and P.a S9,P.a S10 from ‘Xinshiji’,were amplified and cloned. Amplified DNA bands were different sizes: P.a S8 of 927 bp,P.a S9 of 992 bp,P.a S10 of 583 bp,and cDNA bands were 521 bp,521 bp,479 bp,respectively. The results of Blastn in GenBank showed that they were novel S-RNase genes and they have been deposited in GenBank (Accession No.: AY884212,AY864826,AY864825,AY853594 and AY846872). Genomic sequences showed an intron structure between C1 and C5 region. The introns of P.a S8,P.a S9,and P.a S10 were 406 bp,471 bp,104 bp and lay in the hypervariable region (RHV) between C2 and C3. Three genes were compared and displayed similarity at the nucleotide and deduced amino acid level. Most of amino acid sequences of S-RNase gene in Prunoideae (Rosaceae) were used to form their phyligenetic tree. The evolutionary relationships showed S-RNase genes did not form a distinct cluster within species. Intra-species similarity was not higher than inter-species one. Therefore,we speculated that the evolutionary of S-RNase genes in Prunoideae was not consisted with that of species.展开更多
基金financially supported by the National Key Research and Development Program of China (2018YFD1000107)the open research project of the "Cross-Cooperative Team" of the Germplasm Bank of Wild Species to A.Z.
文摘The T2/RNase gene family is widespread in eukaryotes,and particular members of this family play critical roles in the gametophytic self-incompatibility(GSI) system in plants.Wild diploid strawberry(Fragaria)species have diversified their sexual systems via self-incompatible and self-compatible traits,yet how these traits evolved in Fragaria remains elusive.By integrating the published and de novo assembled genomes and the newly generated RNA-seq data,members of the RNase T2 gene family were systematically identified in six Fragaria species,including three self-incompatible species(Fragaria nipponica,Fragaria nubicola,and Fragaria viridis) and three self-compatible species(Fragaria nilgerrensis,Fragaria vesca,and Fragaria iinumae).In total,115 RNase T2 genes were identified in the six Fragaria genomes and can be classified into three classes(Ⅰ-Ⅲ) according to phylogenetic analysis.The identified RNase T2 genes could be divided into 22 homologous gene sets according to amino acid sequence similarity and phylogenetic and syntenic relationships.We found that extensive gene loss and pseudogenization coupled with small-scale duplications mainly accounted for variations in the RNase T2 gene numbers in Fragaria.Multiple copies of homologous genes were mainly generated from tandem and segmental duplication events.Furthermore,we newly identified five S-RNase genes in three self-incompatible Fragaria genomes,including two in F.nipponica,two in F.viridis,and one in F.nubicola,which fit for typical features of a pistil determinant,including highly pistil-specific expression,highly polymorphic proteins and alkaline isoelectric point(pI),while no S-RNase genes were found in all three selfcompatible Fragaria species.Surprisingly,these T2/S-RNase genes contain at least one large intron(>10 kb).This study revealed that the rapid evolution of T2/S-RNase genes within the Fragaria genus could be associated with its sexual mode,and repeated evolution of the self-compatible traits in Fragaria was convergent via losses of S-RNase.
文摘A new selfincompatibility gene was isolated and identified from Pyrus bretschneideri cultivars of Yingzhiqing and Daaoao via PCR amplification, DNA sequence analysis and cross pollination tests. DNA sequence analysis revealed that the isolated fragment displayed a high homology with S 1 ～S 11 allele, and the identity to S 1 ～S 11 allele at the deduced amino level ranged from 56% to 72%; the high degree of variances in the hypervariable （HV） region resulted from the presence of substitution, deletion and insertion of 9 to 15 amino acids. The new Sallele was named S 12 RNase and its accession number was AY250987 in GeneBank. The sizes of HV region, intron, signal peptide, C1 region, C2 region were 39 AA, 341 bp, 27 AA, 11 AA and 10 AA, respectively. The cross pollination tests were carried out using Pyrus pyrifolia cultivars that contained S 1 ～S9RNase genes as female parents, and the cultivars of Daaoao and Yingzhiqing as male parents, respectively. The results showed that all of {%P.pyrifolia%} cultivars were compatible with Daaoao and Yingzhiqing, whereas the cross pollination between Daaoao and Yingzhiqing were incompatible, further confirming that the DNA fragment isolated was a new Sgene.
文摘Frozen young leaves of apricot(Armeniaca vulgaris) ‘Katy’ and ‘Xinshiji’ were used for isolation of total DNA. Total RNA was isolated from their styles at the balloon stage. DNA and cDNA were amplified through PCR using AS1 Ⅱ and ArmyC5R as primers designed according to the conserved (C1,C5) sequences of Rosaceae S-RNases. Three S-RNase genes,P.a S8 from ‘Katy’ and P.a S9,P.a S10 from ‘Xinshiji’,were amplified and cloned. Amplified DNA bands were different sizes: P.a S8 of 927 bp,P.a S9 of 992 bp,P.a S10 of 583 bp,and cDNA bands were 521 bp,521 bp,479 bp,respectively. The results of Blastn in GenBank showed that they were novel S-RNase genes and they have been deposited in GenBank (Accession No.: AY884212,AY864826,AY864825,AY853594 and AY846872). Genomic sequences showed an intron structure between C1 and C5 region. The introns of P.a S8,P.a S9,and P.a S10 were 406 bp,471 bp,104 bp and lay in the hypervariable region (RHV) between C2 and C3. Three genes were compared and displayed similarity at the nucleotide and deduced amino acid level. Most of amino acid sequences of S-RNase gene in Prunoideae (Rosaceae) were used to form their phyligenetic tree. The evolutionary relationships showed S-RNase genes did not form a distinct cluster within species. Intra-species similarity was not higher than inter-species one. Therefore,we speculated that the evolutionary of S-RNase genes in Prunoideae was not consisted with that of species.
