Characterization of new allele influencing flowering time in bread wheat introgressed from Triticum militinae

Ivaničová, Zuzana; Jakobson, Irena; Reis, Diana; Šafář, Jan; Milec, Zbyněk; Abrouk, Michaël; Doležel, Jaroslav; Järve, Kadri; Valárik, Miroslav

doi:10.1016/j.nbt.2016.01.008

Cited by 18 publications

(22 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…3). This insertion of 424 bp long was found to be 99 % identical to the previously identified MITE element in the VRN-A1f-like allele of T. militinae [17]. In order to confirm this result, we used the primer pair mitef/ miter targeting the right junction of the insertion (Table 1; Fig.…”

Section: Resultssupporting

confidence: 56%

The occurrence of spring forms in tetraploid Timopheevi wheat is associated with variation in the first intron of the VRN-A1 gene

2016

View full text Add to dashboard Cite

Background Triticum araraticum and Triticum timopheevii are tetraploid species of the Timopheevi group. The former includes both winter and spring forms with a predominance of winter forms, whereas T. timopheevii is considered a spring species. In order to clarify the origin of the spring growth habit in T. timopheevii, allelic variability of the VRN-1 gene was investigated in a set of accessions of both tetraploid species, together with the diploid species Ae. speltoides, presumed donor of the G genome to these tetraploids.ResultsThe promoter region of the VRN-A1 locus in all studied tetraploid accessions of both T. araraticum and T. timopheevii represents the previously described allele VRN-A1f with a 50 bp deletion near the start codon. Three additional alleles were identified namely, VRN-A1f-del, VRN-A1f-ins and VRN-A1f-del/ins, which contained large mutations in the first (1st) intron of VRN-A1. The first allele, carrying a deletion of 2.7 kb in a central part of intron 1, occurred in a few accessions of T. araraticum and no accessions of T. timopheevii. The VRN-A1f-ins allele, containing the insertion of a 0.4 kb MITE element about 0.4 kb upstream from the start of intron 1, and allele VRN-A1f-del/ins having this insertion coupled with a deletion of 2.7 kb are characteristic only for T. timopheevii. Allelic variation at the VRN-G1 locus includes the previously described allele VRN-G1a (with the insertion of a 0.2 kb MITE in the promoter) found in a few accessions of both tetraploid species. We showed that alleles VRN-A1f-del and VRN-G1a have no association with the spring growth habit, while in all accessions of T. timopheevii this habit was associated with the dominant VRN-A1f-ins and VRN-A1f-del/ins alleles. None of the Ae. speltoides accessions included in this study had changes in the promoter or 1st intron regions of VRN-1 which might confer a spring growth habit. The VRN-1 promoter sequences analyzed herein and downloaded from databases have been used to construct a phylogram to assess the time of divergence of Ae. speltoides in relation to other wheat species.ConclusionsAmong accessions of T. araraticum, the preferentially winter predecessor of T. timopheevii, two large mutations were found in both VRN-A1 and VRN-G1 loci (VRN-A1f-del and VRN-G1a) that were found to have no effect on vernalization requirements. Spring tetraploid T. timopheevii had one VRN-1 allele in common for two species (VRN-G1a), and two that were specific (VRN-A1f-ins, VRN-A1f-del/ins). The latter alleles include mutations in the 1st intron of VRN-A1 and also share a 0.4 kb MITE insertion near the start of intron 1. We suggested that this insertion resulted in a spring growth habit in a progenitor of T. timopheevii which has probably been selected during subsequent domestication. The phylogram constructed on the basis of the VRN-1 promoter sequences confirmed the early divergence (~3.5 MYA) of the ancestor(s) of the B/G genomes from Ae. speltoides.Electronic supplementary materialThe online version of this article (doi:10.1186/s1...

show abstract

Section: Resultssupporting

confidence: 56%

The occurrence of spring forms in tetraploid Timopheevi wheat is associated with variation in the first intron of the VRN-A1 gene

2016

View full text Add to dashboard Cite

show abstract

“…Vrn-B1dic allele is characterized by unexpected high dissimilarity in compare to the vrn-B1 allele. If we exclude the deletions and insertions cases the other dominant alleles of VNR1 genes of di- and polyploidy wheats differ from recessive alleles by several SNPs [19, 22, 23, 27, 29]. Alternatively, we could suggest that the Vrn-B1dic represent the pseudogene copy originated by duplication within one genome.…”

Section: Discussionmentioning

confidence: 99%

“…[17, 19]. Novel allelic variant VRN-A1f-like identified by Ivaničová et al [23] possess mutations in both promoter and first intron regions of VRN-A1 , while only mutations within first intron is the reason of the spring growth habit of T. militinae accession.…”

Section: Introductionmentioning

confidence: 99%

“…and T. spelta L [19]. Seven dominant alleles of the VRN-A1 gene, Vrn-A1a.1 , Vrn-A1a.2 , Vrn-A1b (Vrn-A1b.1) , Vrn-A1b.2 , Vrn-A1b.6 , Vrn-A1c and Vrn-A1f were found in hexaploid wheat [16, 19, 20, 22, 23]. The majority of the spring cultivars carry a Vrn-A1a.1 allele that has a miniature inverted-repeat transposable element (MITE) insertion and duplication in the promoter region [19].…”

Section: Introductionmentioning

confidence: 99%

“…The majority of the spring cultivars carry a Vrn-A1a.1 allele that has a miniature inverted-repeat transposable element (MITE) insertion and duplication in the promoter region [19]. Vrn-A1b allelic variants and Vrn-A1f allele have mutations and deletions of variable lengths in the promoter region, whereas Vrn-A1c has a deletion in the first intron in comparison to the recessive vrn-A1 allele [16, 19, 20, 22, 23]. Most of the dominant alleles of VRN-B1 and VRN-D1 genes possess deletions in the first intron ( Vrn-B1a , Vrn-B1b , Vrn-B1c and Vrn-D1a ) [16, 19, 22, 24–27].…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

VRN1 genes variability in tetraploid wheat species with a spring growth habit

et al. 2016

View full text Add to dashboard Cite

BackgroundVernalization genes VRN1 play a major role in the transition from vegetative to reproductive growth in wheat. In di-, tetra- and hexaploid wheats the presence of a dominant allele of at least one VRN1 gene homologue (Vrn-A1, Vrn-B1, Vrn-G1 or Vrn-D1) determines the spring growth habit. Allelic variation between the Vrn-1 and vrn-1 alleles relies on mutations in the promoter region or the first intron. The origin and variability of the dominant VRN1 alleles, determining the spring growth habit in tetraploid wheat species have been poorly studied.ResultsHere we analyzed the growth habit of 228 tetraploid wheat species accessions and 25 % of them were spring type. We analyzed the promoter and first intron regions of VRN1 genes in 57 spring accessions of tetraploid wheats. The spring growth habit of most studied spring accessions was determined by previously identified dominant alleles of VRN1 genes. Genetic experiments proof the dominant inheritance of Vrn-A1d allele which was widely distributed across the accessions of Triticum dicoccoides. Two novel alleles were discovered and designated as Vrn-A1b.7 and Vrn-B1dic. Vrn-A1b.7 had deletions of 20 bp located 137 bp upstream of the start codon and mutations within the VRN-box when compared to the recessive allele of vrn-A1. So far the Vrn-A1d allele was identified only in spring accessions of the T. dicoccoides and T. turgidum species. Vrn-B1dic was identified in T. dicoccoides IG46225 and had 11 % sequence dissimilarity in comparison to the promoter of vrn-B1. The presence of Vrn-A1b.7 and Vrn-B1dic alleles is a predicted cause of the spring growth habit of studied accessions of tetraploid species. Three spring accessions T. aethiopicum K-19059, T. turanicum K-31693 and T. turgidum cv. Blancal possess recessive alleles of both VRN-A1 and VRN-B1 genes. Further investigations are required to determine the source of spring growth habit of these accessions.ConclusionsNew allelic variants of the VRN-A1 and VRN-B1 genes were identified in spring accessions of tetraploid wheats. The origin and evolution of VRN-A1 alleles in di- and tetraploid wheat species was discussed.Electronic supplementary materialThe online version of this article (doi:10.1186/s12870-016-0924-z) contains supplementary material, which is available to authorized users.

show abstract

Divergence between bread wheat and Triticum militinae in the powdery mildew resistance QPm.tut-4A locus and its implications for cloning of the resistance gene

et al. 2018

Self Cite

View full text Add to dashboard Cite

A segment of Triticum militinae chromosome 7G harbors a gene(s) conferring powdery mildew resistance which is effective at both the seedling and the adult plant stages when transferred into bread wheat ( T. aestivum ). The introgressed segment replaces a piece of wheat chromosome arm 4AL. An analysis of segregating materials generated to positionally clone the gene highlighted that in a plant heterozygous for the introgression segment, only limited recombination occurs between the introgressed region and bread wheat 4A. Nevertheless, 75 genetic markers were successfully placed within the region, thereby confining the gene to a 0.012 cM window along the 4AL arm. In a background lacking the Ph1 locus, the localized rate of recombination was raised 33-fold, enabling the reduction in the length of the region containing the resistance gene to a 480 kbp stretch harboring 12 predicted genes. The substituted segment in the reference sequence of bread wheat cv. Chinese Spring is longer (640 kbp) and harbors 16 genes. A comparison of the segments’ sequences revealed a high degree of divergence with respect to both their gene content and nucleotide sequence. Of the 12 T. militinae genes, only four have a homolog in cv. Chinese Spring. Possible candidate genes for the resistance have been identified based on function predicted from their sequence. Electronic supplementary material The online version of this article (10.1007/s00122-018-3259-3) contains supplementary material, which is available to authorized users.

show abstract

Characterization of new allele influencing flowering time in bread wheat introgressed from Triticum militinae

Cited by 18 publications

References 42 publications

The occurrence of spring forms in tetraploid Timopheevi wheat is associated with variation in the first intron of the VRN-A1 gene

The occurrence of spring forms in tetraploid Timopheevi wheat is associated with variation in the first intron of the VRN-A1 gene

VRN1 genes variability in tetraploid wheat species with a spring growth habit

Divergence between bread wheat and Triticum militinae in the powdery mildew resistance QPm.tut-4A locus and its implications for cloning of the resistance gene

Contact Info

Product

Resources

About