Cold acclimation of tomato plants is associated with differential expression of genes of the SlLHC family, carotenoid metabolism, and chlorophyll accumulation/degradation
Abstract
Tomato ( Solanum lycopersicum L.) is sensitive to cold stress. The plant’s adaptive response to low temperatures is accompanied by cellular osmoregulation and a decrease in the rate of photosynthesis due to disruption of the antennae of photosystems I and II, including proteins of the light-harvesting complex (LHC) family that bind chlorophylls a / b and carotenoids. In this study, a transcriptome analysis of differential expression of SlLHC family genes, carotenoid and abscisic acid (ABA) biosynthesis genes, as well as ORANGE and STAY-GREEN genes associated with chlorophyll accumulation and degradation, was performed for the first time during two cycles (I and II) of “cold stress (12 h) – recovery (60 h)”. The tomato cultivar Otradnyi was used for the analysis. 12 h before the end of the recovery period of the second cycle (II-48), the content of chlorophylls a / b and carotenoids in plant leaves was shown to be significantly decreased. It was revealed that 12 h of cold exposure in both cycles (I-12, II-12) suppressed the expression of most LHC family genes. At the same time points, a significant increase in the transcript levels of the NSY , CCD-like , LeNCED1 and NCED6 genes associated with ABA synthesis was detected. Genes, expression profile of which differed between the primary and repeated cycles of cold exposure, were identified. Based on these data, a list of candidate genes for cold stress memory markers in plants was compiled: 10 SlLHC family genes ( Cab-1A , Cab-1D , CAB12 , CAB5 LOC101257186, SEP2 , OHP2 -LOC101259223, OHP1 and LIL3-2 -LOC101247899) and five genes associated with ABA synthesis ( VDE , CCD4 , CCD-like , LeNCED1 and NCED6 ). The obtained results are important for identifying and understanding the involvement of photosynthesis-related genes in the response to cold stress and determining cold tolerance of tomato plants, and can be used in breeding cold-resistant varieties.