Transgenic rice Oryza glaberrima with higher CPD photolyase activity alleviates UVB-caused growth inhibition

Abstract

The ultraviolet B (UVB) sensitivity of rice cultivated in Asia and Africa varies greatly, with African rice cultivars ( Oryza glaberrima Steud. and O. barthii A. Chev.) being more sensitive to UVB because of their low cyclobutane pyrimidine dimer (CPD) photolyase activity, which is a CPD repair enzyme, relative to Asian rice cultivars ( O. sativa L.). Hence, the production of UVB-resistant African rice with augmented CPD photolyase activity is of great importance, although difficulty in transforming the African rice cultivars to this end has been reported. Here, we successfully produced overexpressing transgenic African rice with higher CPD photolyase activity by modifying media conditions for callus induction and regeneration using the parental line (PL), UVB-sensitive African rice TOG12380 ( O. glaberrima ). The overexpressing transgenic African rice carried a single copy of the CPD photolyase enzyme, with a 4.4-fold higher level of CPD photolyase transcripts and 2.6-fold higher activity than its PL counterpart. When the plants were grown for 21 days in a growth chamber under visible radiation or with supplementary various UVB radiation, the overexpressing transgenic plants have a significantly increased UVB resistance index compared to PL plants. These results strongly suggest that CPD photolyase remains an essential factor for tolerating UVB radiation stress in African rice. As a result, African rice cultivars with overexpressed CPD photolyase may survive better in tropical areas more prone to UVB radiation stress, including Africa. Collectively, our results provide strong evidence that CPD photolyase is a useful biotechnological tool for reducing UVB-induced growth inhibition in African rice crops of O. glaberrima .

UVB-Pretreatment-Enhanced Cadmium Absorption and Enrichment in Poplar Plants

“…In accordance with our experimental results, the plants became shorter and their leaves became more yellow after the Cd treatment (Figure 1a-d). In addition, when the plants were exposed to UVB radiation for a certain amount of time and intensity, their height decreased [27]. After the UVB treatment in poplar trees, under the Cd treatment, the plants will dwarf and their leaves will turn yellow (Figure 1f-h).…”

Poaceae plants transfer cyclobutane pyrimidine dimer photolyase to chloroplasts for ultraviolet-B resistance

“…The accumulation of DNA damage induces mutations or cell death by impeding replication and transcription, thereby inhibiting plant growth and development. CPDs are the principal cause of UV-B-induced growth inhibition in rice ( Oryza sative ) plants grown under supplementary UV-B radiation ( Hidema et al 2007 ; Teranishi et al 2012 ; Mmbando et al 2021 ).…”

The legal aspect of the current use of genetically modified organisms in Kenya, Tanzania, and Uganda

“…Additionally, GE helps create crops with better quality or storage capabilities, like higher vitamin A content 3 and increased resistance to abiotic stress such as ultraviolet-B radiation. 4 Reduced pesticide and insecticide use, the development of pathogen-resistant GM crops, the development of climate and drought-resistant crops, the development of crops with shorter harvesting times and higher yields, improved nutrition composition, decreased toxicology, and increased food security are just a few of the reasons why GM crops should be adopted in Africa. 1 , 5 However, in recent years, East African countries like Kenya, Tanzania, and Uganda have largely been devoid of information about the use of these GMOs.…”