Mutation in the seed storage protein kafirin creates a high-value food trait in sorghum.
Sustainable food production for the earth's fast-growing population is a major challenge for breeding new high-yielding crops, but enhancing the nutritional quality of staple crops can potentially offset limitations associated with yield increases. Sorghum has immense value as a staple food item for humans in Africa, but it is poorly digested. Although a mutant exhibiting high-protein digestibility and lysine content has market potential, the molecular nature of the mutation is previously unknown. Here, building on knowledge from maize mutants, we take a direct approach and find that the high-digestible sorghum phenotype is tightly linked to a single-point mutation, rendering the signal peptide of a seed storage protein kafirin resistant to processing, indirectly reducing lysine-poor kafirins and thereby increasing lysine-rich proteins in the seeds. These findings indicate that a molecular marker can be used to accelerate introduction of this high nutrition and digestibility trait into different sorghum varieties.
Waksman Institute of Microbiology, Rutgers University, 190 Frelinghuysen Road, Piscataway, New Jersey 08854, USA.
Yongrui
Y
Wu
Lingling
L
Yuan
Xiaomei
X
Guo
David R
DR
Holding
Joachim
J
Messing
D000595:Amino Acid Sequence; D001483:Base Sequence; D032461:Chromosomes, Plant / Q000235:genetics; D017124:Conserved Sequence / Q000235:genetics; D056625:Endosperm / Q000648:ultrastructure; D005502:Food; D008040:Genetic Linkage; D005819:Genetic Markers; D008239:Lysine / Q000235:genetics; D018895:Microsatellite Repeats / Q000235:genetics; D008969:Molecular Sequence Data; D050505:Mutant Proteins / Q000737:chemistry / Q000235:genetics; D009154:Mutation / Q000235:genetics*; D020125:Mutation, Missense / Q000235:genetics; D010641:Phenotype; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics*; D055315:Prolamins / Q000737:chemistry; D021382:Protein Sorting Signals; D019655:Quantitative Trait, Heritable; D055314:Seed Storage Proteins / Q000235:genetics*; D016415:Sequence Alignment; D045868:Sorghum / Q000235:genetics* / Q000648:ultrastructure; D003313:Zea mays / Q000648:ultrastructure
D005819:Genetic Markers; D050505:Mutant Proteins; D010940:Plant Proteins; D055315:Prolamins; D021382:Protein Sorting Signals; D055314:Seed Storage Proteins; C080615:kafirin protein, Sorghum bicolor; D008239:Lysine