A drought-responsive rice amidohydrolase is the elusive plant guanine deaminase with the potential to modulate the epigenome.

ABSTRACT: Drought stress in plants causes differential expression of numerous genes. One of these differentially expressed genes in rice is a specific amidohydrolase. We characterized this amidohydrolase gene on the rice chromosome 12 as the first plant guanine deaminase (OsGDA1). The biochemical activity of GDA is known from tea and coffee plants where its catalytic product, xanthine, is the precursor for theine and caffeine. However, no plant gene that is coding for GDA is known so far. Recombinant OsGDA1 converted guanine to xanthine in vitro. Measurement of guanine and xanthine contents in the OsGDA1 knockout (KO) line and in the wild type Tainung 67 rice plants also suggested GDA activity in vivo. The content of cellular xanthine is important because of its catabolic products allantoin, ureides

SUBMITTER: Gotarkar D 

PROVIDER: S-EPMC8360030 | biostudies-literature | 2021 Aug

REPOSITORIES: biostudies-literature