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High molecular weight glutenin subunits (HMW GS) represent an important fraction of endosperm-specific seed-storage proteins that provide elasticity to bread dough. Previously, the second cis-regulatory module (CRM2) was found to be one of the most conserved part of HMW GS promoters, which indicated its pre-eminent role in their gene regulation. Here, we observed that deletion of CRM2 from the promoters of the Bx7 and By8 HMW GS genes increased the leakage of their transient expression in wheat leaf tissue. The effect of a VP1, an Myb and an antisense bZIP transcription factor (TF)-binding site, potentially involved in endosperm-specific regulation within CRM2, was then studied. The activity of a Bx7 gene promoter containing a mutant CRM2 with altered VP1 and Myb TF-binding sites, but an intact bZIP TF-binding site, was similarly low to that of the wild type in leaves. Transactivation analysis and EMSA indicated the binding of TFs TabZIP34 and TabZIP115 to the Skn-1 motif GTCAT in CRM2 and the repression of Bx7 and By8 HMW GS gene promoter activity in leaves. TabZIP34 and TabZIP115 may be involved in the downregulation of HMW GS gene expression in vegetative tissues and early-stage endosperm as well its modulation during seed maturation.

The perennial Secale cereanum cultivar ‘Kriszta’ is an artificial hybrid of S. cereale and S. strictum ssp. anatolicum. From the cross between the wheat line Mv9kr1 and ‘Kriszta’, which aimed the transfer of beneficial traits from rye to wheat, numerous translocation lines have been produced. For the identification of the translocated chromosomes, the unambiguous differentiation between chromosome arms of ‘Kriszta’ is essential. The identification of its short chromosome arms using conventional FISH probes is easy, but because of their similar hybridization patterns, its long arms cannot be distinguished. The present study aimed to create the detailed karyotype of ‘Kriszta’, especially that of long arms, by both chromosome measurements and FISH using highly repetitive, as well as subtelomeric tandem repeat, and synthetic microsatellite DNA sequences. Our results indicate that the chromosome complement of ‘Kriszta’ is not a simple combination of the chromosomes of the parental rye species but is composed of rearranged chromosomes. It is also showed that an adequate pair-wise combination of the DNA sequences pSc119.2, pSc200, pSc250, and (AAC)5 makes it possible to identify any of the long arms of S. cereanum cv. Kriszta chromosomes. The future usability of the identified wheat- ‘Kriszta’ translocated chromosomes is also discussed.

Grain dietary fiber content is an important health-promoting trait of bread wheat. A dominant dietary fiber component of wheat is the cell wall polysaccharide arabinoxylan and the goatgrass

Effective utilization of genetic diversity in wild relatives to improve wheat requires recombination between wheat and alien chromosomes. However, this is suppressed by the

High-molecular-weight glutenin subunit (HMW GS) proteins are major components of the gluten matrix, which is the physical basis of bread-making in wheat. Epigenetic and transcriptional regulations of HMW GS genes were studied both in silico and in wet lab to understand their tissue (endosperm) specific expression. Our co-expressional network analysis identified key transcription factor (TF) genes that regulate HMW GS genes. We also show here that HMW GS genes are inhibited in vegetative tissues by histone deacetylation as revealed by strong GUS expression in vascular tissues of transgenic barley seedlings harbouring HMW GS gene promoter::uidA-reporter gene fusions upon treatment with a histone deacetylase inhibitor. A novel method termed in vivo DNA affinity purification (IP) has been developed here for the isolation of histones and transcription factors binding to target DNA regions. The technique is based on the biolistic introduction of biotinylated PCR probes amplified from HMW GS gene promoters into wheat leaves. Twenty-four hours later, the probe is cross-linked with interacting factors and subsequently re-purified from plant nuclear extracts. Many proteins, ribosomal proteins and histones have so far been isolated. No lysine-acetylated histone protein fragments were found which further highlight the inhibiting effect of histone deacetylation on HMW GS gene expression.

Understanding the genetic diversity of Aegilops biuncialis, a valuable source of agronomical useful genes, may significantly facilitate the introgression breeding of wheat. The genetic diversity and population structure of 86 Ae. biuncialis genotypes were investigated by 32700 DArT markers with the simultaneous application of three statistical methods— neighbor-joining clustering, Principal Coordinate Analysis, and the Bayesian approach to classification. The collection of Ae. biuncialis accessions was divided into five groups that correlated well with their eco-geographic habitat: A (North Africa), B (mainly from Balkans), C (Kosovo and Near East), D (Turkey, Crimea, and Peloponnese), and E (Azerbaijan and the Levant region). The diversity between the Ae. biuncialis accessions for a phenological trait (heading time), which is of decisive importance in the adaptation of plants to different eco-geographical environments, was studied over 3 years. A comparison of the intraspecific variation in the heading time trait by means of analysis of variance and principal component analysis revealed four phenotypic categories showing association with the genetic structure and geographic distribution, except for minor differences. The detailed exploration of genetic and phenologic divergence provides an insight into the adaptation capacity of Ae. biuncialis, identifying promising genotypes that could be utilized for wheat improvement.

Understanding the genetic diversity of Aegilops biuncialis, a valuable source of agronomical useful genes, may significantly facilitate the introgression breeding of wheat. The genetic diversity and population structure of 86 Ae. biuncialis genotypes were investigated by 32700 DArT markers with the simultaneous application of three statistical methods— neighbor-joining clustering, Principal Coordinate Analysis, and the Bayesian approach to classification. The collection of Ae. biuncialis accessions was divided into five groups that correlated well with their eco-geographic habitat: A (North Africa), B (mainly from Balkans), C (Kosovo and Near East), D (Turkey, Crimea, and Peloponnese), and E (Azerbaijan and the Levant region). The diversity between the Ae. biuncialis accessions for a phenological trait (heading time), which is of decisive importance in the adaptation of plants to different eco-geographical environments, was studied over 3 years. A comparison of the intraspecific variation in the heading time trait by means of analysis of variance and principal component analysis revealed four phenotypic categories showing association with the genetic structure and geographic distribution, except for minor differences. The detailed exploration of genetic and phenologic divergence provides an insight into the adaptation capacity of Ae. biuncialis, identifying promising genotypes that could be utilized for wheat improvement.