Inheritance of Kunitz Trypsin Inhibitor and P34 Protein in Soybean Seed

Abstract

Soybean [Glycine max (L.) Merr.] protein is a high quality source for food and feed. But, antinutritional factors in the raw mature soybean are exist. Kunitz trypsin inhibitor (KTI) protein is a main antinutritional factor in soybean seed. Also, P34 protein, referred as Gly m Bd 30K, has been identified as a predominant immunodominant allergen. Genetic relationship between KTI protein and P34 protein could be useful in soybean breeding program for the genetic elimination or reduction of these factors. The objective of this study was to determine the independent inheritance or linkage between KTI protein and P34 protein in soybean seed. A total of 479 F2 seeds were obtained from the cross of 07B1 and PI567476 parents. KTI protein and relative amount of P34 protein were analysed from F 2 seeds harvested from the F1 plants by using SDS-PAGE and Western blot analysis. The segregation ratios of 3 : 1 for KTI protein (353 KTI protein present : 126 KTI protein absent) and relative amount of P34 protein (363 normal amount of P34 protein : 116 low amount of P34 protein). The segregation ratio of 3 : 1 suggested that KTI protein and relative amount of P34 protein in mature soybean seed were controlled by a single major gene. The segregation ratios of 9 : 3 : 3 : 1 (266 KTI protein present, normal amount of P34 protein: 88 KTI protein present, low amount of P34 protein: 102 KTI protein absent, normal amount of P34 protein: 23 KTI protein absent, low amount of P34 protein) and Chi-square value (χ 2 =3.31, P=0.346) were observed in F2 seeds. This data showed that KTI protein was inherited independently with relative amount of P34 protein in soybean. These results will be helpful in breeding program for selecting the line with lacking KTI protein and reduced amount of P34 protein in soybean.

Development of a green soybean line with a green cotyledon and a tetra null genotype for P34, lectin, Kunitz trypsin inhibitor, and lipoxygenase proteins

“…To determine the absence or presence of P34 protein in the F 2 seed generation, the segregation ratio was fitted to an expected ratio of 3:1 (χ 2 = 2.95, p = 0.05 -0.10 at α = 0.05). This data was in agreement with previous studies reporting that the absence or presence of P34 protein is controlled by a single gene (Choi et al 2022;Han et al 2012;Joseph et al 2006). Among 72 F 2 seeds obtained from the cross of parents with a green cotyledon and a green seed coat, 22 F 2 seeds contained no P34 protein, which was suitable for a ratio of 3:1 (Choi et al 2022).…”

“…Among 72 F 2 seeds obtained from the cross of parents with a green cotyledon and a green seed coat, 22 F 2 seeds contained no P34 protein, which was suitable for a ratio of 3:1 (Choi et al 2022). The segregation of a 3:1 ratio for P34 protein was observed in 479 F 2 seeds obtained from a crossing between parents with a green cotyledon and a black seed coat (Han et al 2012).…”