Work

Screening of low-light-tolerant potato varieties and cloning and functional analysis of the transcription factor gene StPIF3

Year: 2026

Type: article

Abstract: Based on measurements and comparisons of growth traits, chlorophyll fluorescence parameters, and other related indices in nine potato varieties under low-light treatment, the cultivar “Atlantic” was identified as low-light tolerant by principal component analysis. To investigate genes involved in the low-light response of “Atlantic”, we performed transcriptome analysis after treatment with a light intensity of 10 μmol m-2 s-1 for 48 h. Using GO enrichment, KEGG pathway analysis, and transcription factor prediction, we identified the light-responsive transcription factor gene StPIF3 and cloned its full-length cDNA. StPIF3 was introduced into tobacco via agrobacterium-mediated transformation, and T1 transgenic lines were obtained by selfing. Bioinformatics analysis, RT-qPCR, and chlorophyll fluorescence measurements were used to characterize and validate its function. StPIF3 encodes a 716-amino-acid protein with a predicted molecular weight of 76.77 kD and an isoelectric point of 7.26, and it is predicted to be hydrophilic and unstable. The StPIF3 protein contains a typical HLH domain and belongs to the bHLH family; phylogenetic analysis indicated that StPIF3 is most closely related to the tobacco homolog. Under 50 μmol m-2 s-1 light intensity, transgenic tobacco plants showed significantly higher Fv/Fm, qP, ETR, ETRmax, and SPAD values than wild-type plants, whereas F0 was lower. Overall, overexpression of StPIF3 markedly improves electron transport and light energy use efficiency, thereby enhancing photosynthetic performance and low-light tolerance.

Source: ACTA AGRONOMICA SINICA

DOI: 10.3724/sp.j.1006.2026.54135