Exploring the Impact of Low Light Intensity on DNA Methylation in Agave angustifolia Haw. Albino Variant

Abstract

Light is an essential environmental factor that regulates important plant processes, including photosynthesis, photoprotection, and the accumulation of pigments such as chlorophylls and carotenoids. Conversely, the absence of light initiates the etiolation phenomenon, characterized by a decrease in photosynthetic and photoprotective pigments. In contrast, albinism is a rare variant characterized by the absence of chloroplasts, chlorophyll, and other pigments, even in the presence of light. Albinism may occur spontaneously in plant tissue culture (PTC) and is considered an unexplored phenotypic variant. During micropropagation of Agave angustifolia Haw., two somaclonal variants emerged from green plantlets: albino and variegated. We demonstrate that low-intensity light exposure triggers greener pigmentation in albino plantlets accompanied by an increase in global DNA methylation levels. Our findings suggest the possibility of chloroplast biogenesis under low-intensity light and provide insight into the potential role of DNA methylation in regulating plant responses to light intensity and highlight the importance of studying the effects of different light conditions on plant development and physiology.