Is UV-induced DNA damage greater at higher elevation?

• Published in: American journal of botany Vol. 101; no. 5; pp. 796 - 802
• Main Authors: Wang, Qing-Wei, Hidema, Jun, Hikosaka, Kouki
• Format: Journal Article
• Language: English
• Published: United States Botanical Society of America, Inc 01.05.2014; Botanical Society of America
• Subjects: Altitude; Aquatic plants; Botany; climate change; cyclobutane pyrimidine dimer (CPD); Deoxyribonucleic acid; DNA; DNA Damage; Ecology; elevational effect; Environmental factors; Growing season; leaves; Photosynthesis; photosynthetically active radiation; plant damage; Plant growth; Plant Leaves - radiation effects; Plantago; Plantago - radiation effects; Plantago asiatica; Polygonum - radiation effects; Polygonum sachalinense; Pyrimidine Dimers - analysis; Regression analysis; Reynoutria sachalinensis; Sunlight; temperature; Ultraviolet radiation; Ultraviolet Rays; UV damage; UV‐B radiation; cyclobutane pyrimidine dimer (CPD); UV-B radiation; UV damage; elevational effect; climate change
• DOI: 10.3732/ajb.1400010
• ISSN: 0002-9122; 1537-2197

• Premise of the study: Although ultraviolet radiation (UV) is known to have negative effects on plant growth, there has been no direct evidence that plants growing at higher elevations are more severely affected by ultraviolet‐B (UV‐B) radiation, which is known to increase with elevation. We examined damage to DNA, a primary target of UV‐B, in the widespread species Polygonum sachalinense (Fallopia sachalinensis) and Plantago asiatica at two elevations. • Methods: We sampled leaves of both species at 300 and 1700 m above sea level every 2 h for 11 d across the growing season and determined the level of cyclobutane pyrimidine dimer (CPD), a major product of UV damage to DNA. • Key results: The CPD level was significantly influenced by the time of day, date, elevation, and their interactions in both species. The CPD level tended to be higher at noon or on sunny days. DNA damage was more severe at 1700 m than at 300 m: on average, 8.7% greater at high elevation in P. asiatica and 7.8% greater in P. sachalinense. Stepwise multiple regression analysis indicated that the CPD level was explained mainly by UV‐B and had no significant relationship with other environmental factors such as temperature and photosynthetically active radiation. • Conclusions: UV‐induced DNA damage in plants is greater at higher elevations.