Studying the relation between differential expressed starch genes and bread quality in two wheat cultivars from ۵ to ۲۸ days post anthesis

Wheat endosperm, which is composed of starch, proteins and lipids, is the main flour source in bread industry.The amount and type of starch and its interactions with gluten proteins play key roles in the quality of bread.The aim of this research was to study genes with differential expression and their affected pathways on finalbread quality in two wheat cultivars with high (Pishtaz) and low (Navid) bread quality at ۵, ۱۰, ۱۴, ۲۱ and۲۸ days post anthesis (DPA). The gene expression determined througth RNA-sequencing technique anddiferentially expressed genes identified by downstream bioinformatic analysis. Starch encoding genesselected and their functions and related pathways identified through EMBL-EBI, Pfam and KEGG databases.Results showed that genes encodying Endoglucanase, Beta-fructofuranosidase۱, Alpha-amylase and Enolasehad higher expression in Pishtaz compared to Navid at ۵, ۱۰, ۱۴, ۲۱ and ۲۸ DPA, respectively. These genesare involved in the cellulose hydrolysis, sucrose hydrolysis, starch degradation and glycolysis process,respectively. Alpha-glucosidase at ۵ and ۱۰ DPA, ۱,۴-alpha-glucan-branching enzyme at ۵ DPA and Alphaamylaseat ۲۸ DPA are genes with increased expression in Navid compared to Pishtaz and have roles inmaltose hydrolysis , branching of starch polymer chains and starch degradation, respectively. Based on theresults, it seems that processes linked with starch biosynthesis at ۵ and ۱۰ DPA and starch degradation at ۱۴and ۲۱ DPA have higher activity and produce downstream products in Pishtaz. Also, starch degradationactivity decreases and pyruvate accumulation significantly accured in Pishtaz at ۲۸ DPA. In Pishtaz, contraryto Navid, the reactions are generally towards starch biosynthesis, branching its carbohydrate polymersespecially crystalline structure and higher starch content in endosperm. This is consistent with previousresults that Pishtaz has higher crystallinity in its starch structure and bread quality.

کلیدواژه ها:

Triticum aestivum ، Anthesis ، Grain developement ، RNA sequencing ، Crystallinity