GEOapplication/xmlftp://ftp.ncbi.nlm.nih.gov/geo/series/GSE311nnn/GSE311803/primaryOK200TranscriptomicsArabidopsis thalianaExpression profiling by high throughput sequencinghttps://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE311803GEOGSEfalseRoot meristem growth factor (RGF) peptide signaling as a molecular bridge between root development and non-lethal thermal stress adaptationRoots adapt to temperature ranges that restrict growth without causing lethality, a largely unexplored physiological state. Although lethal heat shock and moderately high temperatures have been studied in detail, the effects of non-lethal high temperatures on root development remain largely unknown. We defined 31°C as a non-lethal thermal stress in Arabidopsis thaliana and examined its impact on root growth using phenotypic analyses and developmental-zone-specific transcriptomics. Under the non-lethal thermal stress (31°C), primary root growth, meristem size, and superoxide (O₂-) accumulation were all reduced, and the distribution of the meristem master regulator PLETHORA2 (PLT2) became restricted. Transcriptome analysis revealed a strong downregulation of RGFs, RGFRs, and PLT2. Mutants of these genes were more sensitive to the stress, whereas RGF1 treatment restored meristem size, increased O₂- levels, and expanded the distribution of PLT2 protein. RGF peptide also promoted lateral root development, resulting in a more complex root system under the thermal stress. These results indicate that the RGF-RGF receptor-PLT2 pathway plays a central role in root adaptation to the non-lethal heat stress and suggest that manipulating RGF signaling could enhance root thermotolerance and crop resilience under elevated temperatures.2026/06/14GSE311803GSM9332355GSM9332366GSM9332365GSM9332354GSM9332368GSM9332357GSM9332367GSM9332356GSM9332359GSM9332358GSM9332369GSM9332360GSM9332370GSM9332362GSM9332351GSM9332361GSM9332353GSM9332364GSM9332363GSM933235230821311803Arabidopsis thaliana