Ultraviolet radiation (UVR) is widely known as deleterious for many organisms since it can cause damage to biomolecules either directly or indirectly via the formation of reactive oxygen species. The goal of this study was to analyze the capacity of high-mountain Espeletia hartwegiana plant phyllosphere microorganisms to survive UVR and to identify genes related to resistance strategies. A strain of Deinococcus swuensis showed a high survival rate of up to 60% after UVR treatment at 800J/m 2 and was used for differential expression analysis using RNA-seq after exposing cells to 400J/m 2 of UVR (with >95% survival rate). Differentially expressed genes were identified using the R-Bioconductor package NOISeq and compared with other reported resistance strategies reported for this genus. Genes identified as being overexpressed included transcriptional regulators and genes involved in protection against damage by UVR. Non-coding (nc)RNAs were also differentially expressed, some of which have not been previously implicated. This study characterized the early resistance strategy used by D. swuensis and indicates the involvement of ncRNAs in the adaptation to extreme environmental conditions. 2 and/or radiation conditions are attractive sources of microorganisms with exceptional 3 phenotypic and genotypic properties. The high-mountain Paramo biome, similar to the 4 tundra biome of high latitudes, consists of high-elevation areas subject to harsh 5 environmental conditions. The Paramo biome has a high solar incidence that can induce 6 damage by ultraviolet radiation (UVR) that represents a survival challenge for 7 organisms [50]. Ionizing radiation and UVR affect organisms by damaging cellular 8 components such as nucleic acids, proteins, and lipids [30]. The deleterious effect on 9 cells is caused by direct damage to DNA, such as chromosomal lesions that introduce 10 both double-strand breaks (DSBs) and single-strand breaks (SSBs), and damage due to 11 pyrimidine dimerization and photoproducts that inhibit DNA replication and 12 July 31, 2019 1/19 transcription [2]. Most of the damage, however, is caused indirectly by the production of 13 reactive oxygen species (ROS), such as the chemically reactive superoxide and hydroxyl 14 radicals that in turn affect various cellular constituents, including proteins [30]. 15 The electromagnetic spectrum of UVR is divided into ultraviolet A (UVA) with 16 wavelengths from 315-400 nm (6.31e-19 -4.97e-19 J/m 2 s), ultraviolet B (UVB, from 17 280-315 nm, 7.10e-19 -6.31e-19 J/m 2 s) and ultraviolet C (UVC, from 100-280 nm, 18 1.99e-18 -7.10e-19 J/m 2 s) [64]. The UV electromagnetic spectrum covering UVB and 19 UVC is considered ionizing radiation [51]. While UVC is absorbed by the ozone layer 20 and the atmosphere, about 8% of UVA and 1% of UVB reach the Earth's surface [51]. 21 The harmful effects of UVR on cellular components depend on the wavelength: UVA 22 can travel farther into tissues and contributes to ROS (damage to lipids, proteins, and 23 DNA) whereas UVB produces direct breaks...