BBM Magazine Issue-Sayı: 61 February - Şubat 2023

BBM • FEBRUARY - ŞUBAT 2023 74 ve 4B kromozomları üzerinde bulunan altı Cupin 1 prote- ini için QTL’ler belirledik (Şekil 3, Tablo 1). Proteinler 045 ve 092’nin QTL’leri 4A’da aynı fiziksel harita konumunda bulunurken, proteinler 040, 054 ve 120’nin QTL’leri 4B’de birbirine çok yakındı. Diğer protein aileleri için başka QTL kümeleri bulduk. Bu QTL’ler 2A üzerinde üç geç embriyo- genez bol proteini, 1B üzerinde aldo/keto redüktaz ailesi- nin iki proteini, 5A üzerinde iki β-amilaz ve 7B üzerinde kitinaz sınıf 1’in iki proteini için bulunur. Potansiyel olarak homolog kromozomal pozisyonlar 5A ve 5B’de iki lipit transfer proteini, 6B ve 6D’de iki bitki antimikrobiyal pro- teini, 7A ve 7B’de üç kitinaz sınıfı 1 proteini ve 1A ve 1B’de iki LMW-GS için QTL’ler için tanımlanmıştır (Şekil 3, Tablo 1). Bu bulgular, önemli gen ailelerinin aynı homolog kromo- zom grubu üzerinde yer aldığı diğer özelliklerle karşılaştı- rılabilir; örneğin, grup 4 kromozomları üzerinde bitki boyu (Rht1 ve Rht2 genleri) veya grup 2 kromozomları üzerinde başaklanma zamanı (Ppd-1 genleri). Özet olarak, bildiğimiz For instance, we identified QTLs for six Cupin 1 proteins, all located on chromosomes 4A and 4B (Figure 3, Table 1). QTLs of proteins 045 and 092 were located on the identi- cal physical map position on 4A, whereas QTLs for proteins 040, 054, and 120 were very close to each other on 4B. We found further QTLs clusters for other protein families. These QTLs are found for three late embryogenesis abundant pro- teins on 2A, two proteins of the aldo/keto reductase family on 1B, two β-amylases on 5A, and two proteins of chitinase class 1 on 7B. Potentially homologous chromosomal posi- tions were identified for QTLs of two lipid transfer proteins on 5A and 5B, two plant antimicrobial proteins on 6B and 6D, three proteins of chitinase class 1 on 7A and 7B, and for two LMW-GS on 1A and 1B (Figure 3, Table 1). These findings are comparable to other traits where important gene fami- lies are located on the same group of homologous chro- mosomes, e.g., for plant height on chromosomes of group 4 (Rht1 and Rht2 genes) or heading time on chromosomes of group 2 (Ppd-1 genes). In summary, to our knowledge, this largest GWAS study on the wheat proteome revealed a similar genetic architecture of proteins as reported for other traits, with major QTLs for 24 out of 114 proteins. QTLS FOR IMPORTANT GLUTEN PROTEINS High and low molecular weight glutenins are of great im- portance for wheat end-use quality. They have been under intensive research and use in wheat breeding since the pio- neering work of Payne and colleagues. We identified three major QTLs underpinning three proteins specifically related to glutenins, one HMW- and two LMW-GS proteins (Table 1). On chromosome 1D, we found a major QTL explaining 42.7% of the genotypic variance for prot017, which is annotated as HMW-Dx5 according to the Uniprot database (Table 1). Elec- trophoretic analysis by SDS-PAGE on our wheat cultivars re- vealed that the QTL allele GG of prot017 was represented by HMW banding unit 5 and the QTL allele AA by the HMW banding unit 2 for a total of 143 out of 148 wheat cultivars, confirming the Uniprot annotation. Interestingly, the allelic difference from the SDS banding pattern could be deduced from the quantitative measurements of a single protein (017), where cultivars with the Dx5 (GG) unit had a lower abun- dance than cultivars with the Dx2 (AA) unit (Figure 4). While it was not possible to qualitatively distinguish the highly homol- ogous protein isoforms by the tryptic peptides quantified by our mass-spectrometry-based proteomics workflow, the ap- parently allele-dependent expression level of the gene prod- uct was perfectly captured by the complementary SDS-PAGE approach. This case study highlights that quantitative protein measurements can provide additional relevant information content to purely genetic analyses for breeding studies. POSSIBILITY TO BREED FOR LOWALLERGEN CONTENT Although wheat is an important and mostly healthy staple crop, a sizeable number of people suffer from wheat sensitivi- SPECIAL COVER • ÖZEL DOSYA