Low expression of carotenoids cleavage dioxygenase 1 (ccd1) gene improves the retention of provitamin-A in maize grains during storage

• Published in: Molecular genetics and genomics : MGG 2021, Vol.296 (1), p.141-153
• Main Authors: Dutta, Suman, Muthusamy, Vignesh, Chhabra, Rashmi, Baveja, Aanchal, Zunjare, Rajkumar U., Mondal, Tapan K., Yadava, Devendra K., Hossain, Firoz
• Format: Article
• Language: English
• Subjects: Alleles; Animal Genetics and Genomics; beta Carotene - chemistry; beta Carotene - metabolism; Beta-Cryptoxanthin - chemistry; Beta-Cryptoxanthin - metabolism; Biochemistry; Biomedical and Life Sciences; Carotenoids; Copy number; Dioxygenase; Dioxygenases - genetics; Dioxygenases - metabolism; Gene Dosage; Gene Expression; Genome, Plant; Genomes; Genotypes; Human Genetics; Hydrolysis; Inbreeding; Life Sciences; Malnutrition; Microbial Genetics and Genomics; Original Article; Plant Breeding; Plant Genetics and Genomics; Plant Proteins - genetics; Plant Proteins - metabolism; Provitamins - chemistry; Provitamins - metabolism; Vitamin A - chemistry; Vitamin A - metabolism; Zea mays - genetics; Zea mays - metabolism; β-Carotene
• ISSN: 1617-4615; 1617-4623
• DOI: 10.1007/s00438-020-01734-1

Provitamin-A (proA) is essentially required for vision in humans but its deficiency affects children and pregnant women especially in the developing world. Biofortified maize rich in proA provides new opportunity for sustainable and cost-effective solution to alleviate malnutrition, however, significant loss of carotenoids during storage reduces its efficacy. Here, we studied the role of carotenoid cleavage dioxygenase 1 ( ccd1 ) gene on degradation of carotenoids in maize. A set of 24 maize inbreds was analyzed for retention of proA during storage. At harvest,  crtRB1 -based maize inbreds possessed significantly high proA (β-carotene: 12.30 µg/g, β-cryptoxanthin: 4.36 µg/g) than the traditional inbreds (β-carotene: 1.74 µg/g, β-cryptoxanthin: 1.28 µg/g). However,  crtRB1 -based inbreds experienced significant degradation of proA carotenoids (β-carotene: 20%, β-cryptoxanthin: 32% retention) following 5 months. Among the  crtRB1 -based genotypes, V335PV had the lowest retention of proA (β-carotene: 1.63 µg/g, β-cryptoxanthin: 0.82 µg/g), while HKI161PV had the highest retention of proA (β-carotene: 4.17 µg/g, β-cryptoxanthin: 2.32 µg/g). Periodical analysis revealed that ~ 60–70% of proA degraded during the first three months. Expression analysis revealed that high expression of  ccd1  led to low retention of proA carotenoids in V335PV, whereas proA retention in HKI161PV was higher due to lower expression. Highest expression of  ccd1  was observed during first 3 months of storage. Copy number of  ccd1  gene varied among yellow maize (1–6 copies) and white maize (7–35 copies) while wild relatives contained 1–4 copies of  ccd1  gene per genome. However, copy number of  ccd1  gene did not exhibit any correlation with proA carotenoids. We concluded that lower expression of  ccd1  gene increased the retention of proA during storage in maize. Favourable allele of  ccd1  can be introgressed into elite maize inbreds for higher retention of proA during storage.